tag:blogger.com,1999:blog-73960575488241403362024-02-06T21:36:27.453-08:00WA0UWH - Electronics & HAM Radio Blog<center>Eldon Brown<br>
My Amateur Radio Station and Project Blog.
<br>
Home: <a href="http://wa0uwh.blogspot.com/">http://WA0UWH.blogspot.com </a> - Grid: <a href="http://no.nonsense.ee/qthmap/?qth=CN88XC35&from=CN88XC35">CN88xc</a><br>Located Near Seattle in Puget Sound<br>and I Love to Build HomeBrew Ham Radio Projects
</center>Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.comBlogger530125tag:blogger.com,1999:blog-7396057548824140336.post-20216093350405906372021-03-30T23:22:00.010-07:002021-03-31T00:37:52.380-07:00More Projects with Telegram<div><br /></div><div><div><b>In the past years I had always blogged my projects, but due to time, effort and format I had stopped doing that. But my projects continued, and I have collected many photographs of them. I missed the interaction with readers of my blog and have always wanted a simpler method. </b></div><div><b><br /></b></div><div><b>I think I have found one: by using "Telegram Channels" , they are simple to setup, and very easy to add content. The one thing lacking is: "No Re-Arrangement" of content, once created and posted, only edits of text (or post deletions) is possible (but I can live with that). It is simple, just: take a photo, share to the Telegram Channel with a little text, and it is DONE (maybe 15 sec of effort).</b></div><div><br /></div><div><b>So this is what I have done with a lot of previous un-posted photos, and I will continue to add new photos and text as progress permits.</b></div><div><b><br /></b></div><div><b>Telegram is normally a social communication APP available for a phone and/or most other hardware.</b></div><div><b><br /></b></div><div><b>The Telegram Channel that I have set are easy to follow, or can be viewed via a workstation browser, as they also have a very short Public link. I have named my group of Channels as "MrFab_<subject>", where the index is a Channel called "MrFab_Index", it can be searched for on Telegram. Or, use the Public Link URL as: </b></div><div><b><br /></b></div><div><b><a href="http://t.me/MrFab_Index" target="_blank">http://t.me/MrFab_Index</a></b></div><div><b><br /></b></div><div><b>This Channel is the Index page for all of my actual Project Channels. If you use the URL in a browser, there will be a button to "Preview Channel" and therefore a new user does not actually have to install the Telegram APP to view the content.</b></div><div><b><br /></b></div><div><b>Finding and developing this Idea was in itself a fun project, I hope I can keep it up. </b></div><div><b><br /></b></div><div><b>If you would like to see my projects feel free to join, or follow as desired.</b></div><div><b><br /></b></div><div><b>Also, feel free to use this Idea to create your own Project Channels, I think you will find it enjoyable and easy. It will provide a historical record of your Projects. If needed I will help with some ideas and pointer to start your efforts.</b></div><div><b><br /></b></div><div><b>Let me know if you find the useful or fun, also feel free to share the URL Link above, thanks.</b></div></div><div><b><span style="font-family: inherit;"><br /></span></b></div><div><b><span style="font-family: inherit;">This Channel is the Index page for all of my actual Project Channels. If you use the URL in a browser, there will be a button to "Preview the Channel" and therefore a new user does not actually have to install Telegram to view the content.</span></b></div><div><b><span style="font-family: inherit;"><br /></span></b></div><div><b><span style="font-family: inherit;">Finding developing this Idea was in itself a fun project, I hope I can keep it up. </span></b></div><div><b><span style="font-family: inherit;"><br /></span></b></div><div><b><span style="font-family: inherit;">If you would like to see my projects feel free to join, or follow as desired.</span></b></div><div><b><span style="font-family: inherit;"><br /></span></b></div><div><span><b><div>Comments Welcome and encouraged via the Telegram APP.</div><div><br /></div><div>But inappropriate comments will be deleted, Spam and Trolls will be banned with out notice.</div></b></span></div><div><b><span style="font-family: inherit;"><br /></span></b></div><div><b><span style="font-family: inherit;"><br /></span></b></div><div><b><span style="font-family: inherit;">Also, feel free to use this Idea to create your own Project Channels, I think you will find it enjoyable and easy. It will provide a historical record of your Projects. If needed I will help with some ideas and pointer to start your efforts.</span></b></div><div><b><span style="font-family: inherit;"><br /></span></b></div><div><b><span style="font-family: inherit;">Let me know if you find the useful or fun, also feel free to share the URL Link above, thanks.</span></b></div>
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-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
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Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-28579186322584817382020-04-15T13:18:00.001-07:002020-04-15T17:08:54.501-07:00More Phi<b>More Phi</b><br />
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<b>Phi</b> is about 1.61803..... (see previous post)<br />
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Interesting values in the following formula; A^2-A<br />
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<b>A=1; A^2 - A = 0.0000....</b><br />
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A=1.60; A^2 - A = 0.9600<br />
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<b>A=Phi; A^2 - A = 1.0000....</b><br />
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A=1.62; A^2 - A = 1.0044<br />
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<b>A=2; A^2 - A = 2.0000....</b><br />
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For all other number besides <b>Phi, </b>with this formula, will equal something other than 1.00000....<br />
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Also interesting;<br />
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<b>A=Phi; A - (1/A) = 1.0000....</b><br />
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Phi in terms of "<b>1</b>";<br />
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<b>Phi = (1+sqrt(1+1+1+1+1)) / (1+1)</b><br />
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-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
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<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-70545562833332622352019-04-29T17:46:00.002-07:002019-04-29T17:46:39.337-07:00More PhiAs seen in my previous post, I enjoy special numbers. Phi is similar to Pi, as it never repeats. As seen from the previous post it is easy to print the value of Phi for as many digits as you like. On my Linux Workstation it took 199 minutes,59 seconds to compute and print.<br />
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Here are the first few and the last few of 1,000,000 digits.<br />
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/home/eldonb<br />
Dogee$ time echo "scale=1000000;((1+sqrt(5))/2)" | bc<br />
1.618033988749894848204586834365638117720309179805762862135448622705\<br />
26046281890244970720720418939113748475408807538689175212663386222353\<br />
69317931800607667263544333890865959395829056383226613199282902678806\<br />
75208766892501711696207032221043216269548626296313614438149758701220\<br />
34080588795445474924618569536486444924104432077134494704956584678850\<br />
98743394422125448770664780915884607499887124007652170575179788341662\<br />
56249407589069704000281210427621771117778053153171410117046665991466\<br />
97987317613560067087480710131795236894275219484353056783002287856997\<br />
82977834784587822891109762500302696156170025046433824377648610283831\<br />
26833037242926752631165339247316711121158818638513316203840052221657\<br />
91286675294654906811317159934323597349498509040947621322298101726107\<br />
05961164562990981629055520852479035240602017279974717534277759277862\<br />
56194320827505131218156285512224809394712341451702237358057727861600\<br />
86883829523045926478780178899219902707769038953219681986151437803149\<br />
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.<br />
.<br />
.<br />
<br />
51205498805479514967289154302996769121988102263194659806380466107909\<br />
31352857957674862371564191289402092625063920284548765631670222354467\<br />
62108166903411674733689654891698040997088225756846422806485457083181\<br />
54817250273792269673672784912715565863640224840546063168807939806419\<br />
10011292989778642634722933479751500991951991756672702399802377950118\<br />
74531421414112149235697793062845603141116573053057593276429408709647\<br />
92714973972713169819730050190640877760201932333501404222064855249240\<br />
36963502091099895258774893289262893136069071641672363453659300940411\<br />
52727279580441683058589433882835637617510166237834248102913501606884\<br />
97828073566475942021829737743512519707760133872287874153226344<br />
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real<span style="white-space: pre;"> </span>199m59.237s<br />
user<span style="white-space: pre;"> </span>199m58.984s<br />
sys<span style="white-space: pre;"> </span>0m0.024s<br />
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/home/eldonb<br />
Dogee$<br />
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<pre>
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-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
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<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-5769961590503476052018-12-21T19:08:00.002-08:002018-12-24T21:48:28.144-08:00My Favorite Irrational Number<br />
I have always been interested in numbers, especially special numbers like Pi (3.1415. . . ).<br />
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Normal whole numbers, like 1, 2, 3, etc (and their negative counter parts) are amazing when you consider there is no end to how far you can go to find a larger number, just by adding one. Within that very large range of numbers, there are many numbers which have their own special properties, for example the "<a href="s://en.wikipedia.org/wiki/Prime_number">Prime Numbers</a>". As with all whole numbers, there is no Largest Prime Number, there is always a larger one to be found.<br />
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The whole numbers (plus/minus) and fractions that can be written using them are known a "Rational Numbers" - meaning that they can be written as a <b>ratio</b> (a fraction), for example: 1/1, 1/2, 1/3, etc.<br />
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But there is another class of numbers that can NOT be written as a ratio of two whole numbers, they are called "Irrational Numbers", for example the value of "P<a href="https://en.wikipedia.org/wiki/Pi">i</a>". Pi can be written with many-many non-repeating digits without end, but Pi could never be written as an exact fraction (a ratio) of two whole numbers. There are many such "Irrational Numbers", many are used in science and found in Nature.<br />
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My favorite Irrational Number can be computed as simple as: <b>(1+sqrt(5))/2</b><br />
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This can be computed with as many digits that you like with a simple Unix command (change that scale as desired for the number of digits):<br />
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<b>echo "scale=1000; (1+sqrt(5))/2" | bc</b><br />
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This is a very special number known as "<a href="https://www.youtube.com/watch?v=5zosU6XTgSY">phi</a>".<br />
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A very interesting property of phi is: <b>1/phi = phi-1</b><br />
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No other number has this simple property.<br />
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Phi is found in many places in Nature, for example it is the way seeds are arranged withing a <a href="https://en.wikipedia.org/wiki/Helianthus">Sun Flower</a>, the size of chambers of the <a href="https://en.wikipedia.org/wiki/Nautilus">Nautilus</a> fish, etc.<br />
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Phi is the name given to what is also called the "<a href="https://en.wikipedia.org/wiki/Golden_ratio">Golden Ratio</a>" or "<a href="https://en.wikipedia.org/wiki/Golden_rectangle">Golden Rectangle</a>".<br />
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Here are the first 1000 digits of <b>Phi</b>:<br />
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1.618033988749894848204586834365638117720309179805762862135448622705<br />
26046281890244970720720418939113748475408807538689175212663386222353<br />
69317931800607667263544333890865959395829056383226613199282902678806<br />
75208766892501711696207032221043216269548626296313614438149758701220<br />
34080588795445474924618569536486444924104432077134494704956584678850<br />
98743394422125448770664780915884607499887124007652170575179788341662<br />
56249407589069704000281210427621771117778053153171410117046665991466<br />
97987317613560067087480710131795236894275219484353056783002287856997<br />
82977834784587822891109762500302696156170025046433824377648610283831<br />
26833037242926752631165339247316711121158818638513316203840052221657<br />
91286675294654906811317159934323597349498509040947621322298101726107<br />
05961164562990981629055520852479035240602017279974717534277759277862<br />
56194320827505131218156285512224809394712341451702237358057727861600<br />
86883829523045926478780178899219902707769038953219681986151437803149<br />
97411069260886742962267575605231727775203536139362<br />
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-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
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<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-57950636195788016222018-04-04T09:00:00.000-07:002018-04-04T09:00:25.271-07:00Hands Free Jig<b>UPDATED:</b><br />
Added Details and Links<br />
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In the past I successfully have used "<a href="https://www.google.com/search?q=hands+free+soldering+jig&rlz=1C1CHFX_enUS710US710&oq=hands+free+soldering+jig">Hands Free Soldering Jigs</a>", but I wanted more functionality.<br />
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I found on ebay Machinist <a href="http://www.ebay.com/bhp/dial-indicator-holder">Magnetic Indicator Dial Gauge Holders</a>, with a little 3D Printer Designed Adaptor they could be used as a Hands Free Soldering Jig.<br />
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A single Knob adjust and locks all three major joints.<br />
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<div class="separator" style="clear: both; text-align: center;">
<a href="https://2.bp.blogspot.com/-QUBNxDPW9pg/WsL3qM1Hm2I/AAAAAAAAN4g/XyL5SQv281Utv_TQK2-bAgvdTlvdtX1ygCKgBGAs/s1600/0402182027.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="900" data-original-width="1600" height="180" src="https://2.bp.blogspot.com/-QUBNxDPW9pg/WsL3qM1Hm2I/AAAAAAAAN4g/XyL5SQv281Utv_TQK2-bAgvdTlvdtX1ygCKgBGAs/s320/0402182027.jpg" width="320" /></a></div>
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In this case, the yellow alligator clip adapter was 3D Printed.<br />
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<div class="separator" style="clear: both; text-align: center;">
<a href="https://3.bp.blogspot.com/-WngkrZadKlA/WsL4ADVOhNI/AAAAAAAAN4k/eJi9VfKhFOE-MaRNZmK3WccJlNZS0XtrwCKgBGAs/s1600/0402182028.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="900" data-original-width="1600" height="180" src="https://3.bp.blogspot.com/-WngkrZadKlA/WsL4ADVOhNI/AAAAAAAAN4k/eJi9VfKhFOE-MaRNZmK3WccJlNZS0XtrwCKgBGAs/s320/0402182028.jpg" width="320" /></a></div>
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Also, another adapter (black) was printed, and a "Hat Pin" heated and inserted. This makes for a very nice PCB probe, an Oscilloscope probe can be attached to the top of the pin.<br />
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<div class="separator" style="clear: both; text-align: center;">
<a href="https://3.bp.blogspot.com/-_UhDRqAfpqg/WsL45tgSKKI/AAAAAAAAN4w/9QBpfr6lrY89DJigsAQi7U1bAi8QDGQDQCKgBGAs/s1600/0402182030.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="900" data-original-width="1600" height="180" src="https://3.bp.blogspot.com/-_UhDRqAfpqg/WsL45tgSKKI/AAAAAAAAN4w/9QBpfr6lrY89DJigsAQi7U1bAi8QDGQDQCKgBGAs/s320/0402182030.jpg" width="320" /></a></div>
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Once adjusted, these Dial Indicator Holders are "Rock Solid", once positioned they stay put, allowing for precise probing. I use tape to hold board under test to the bench (thanks, Jeff - KO7M).<br />
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<a href="https://4.bp.blogspot.com/-5U-8w0C9B5w/WsL8yEflOLI/AAAAAAAAN5Q/ebJxPKJ6fu8MDgWyZYEB44YPXeT4hcPMQCKgBGAs/s1600/0402182101.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="900" data-original-width="1600" height="180" src="https://4.bp.blogspot.com/-5U-8w0C9B5w/WsL8yEflOLI/AAAAAAAAN5Q/ebJxPKJ6fu8MDgWyZYEB44YPXeT4hcPMQCKgBGAs/s320/0402182101.jpg" width="320" /></a></div>
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If used, the Magnet Base needs a stable steel attachment point, in my case, my bench edge is metal and provides as necessary. The Magnet Base could be abandoned for something that could be attached to a wooden bench.<br />
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-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
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<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-74423874347652011152018-04-02T20:14:00.002-07:002018-04-02T20:18:23.719-07:00Test Lead Rack - For my eShopIn my Electronics Shop, space and organization is always a challenge. The following 3D Printed Test Lead Rack will help.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><span style="margin-left: auto; margin-right: auto;"><a href="https://myhub.autodesk360.com/ue2a3aa53/g/shares/SH7f1edQT22b515c761ef190f39442ebb163?viewState=NoIgbgDAdAjCA0IDeAdEAXAngBwKZoC40ARXAZwEsBzAOzXjQEMyzd1C0A2ATgBYBjAEwB2GNwC0ADm6MJvAMwDx3YSPG8AZvMn8x3ACYbVaAL4gAukA"><img border="0" data-original-height="836" data-original-width="1061" height="252" src="https://1.bp.blogspot.com/-mk_nQ5nZ1DA/WsLtwA8Uv-I/AAAAAAAAN3k/0Ah79-IN5dYk4AB9qm4Ww0QTtl4Pft4-gCLcBGAs/s320/Capture.PNG" width="320" /></a></span></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><a href="https://myhub.autodesk360.com/ue2a3aa53/g/shares/SH7f1edQT22b515c761ef190f39442ebb163?viewState=NoIgbgDAdAjCA0IDeAdEAXAngBwKZoC40ARXAZwEsBzAOzXjQEMyzd1C0A2ATgBYBjAEwB2GNwC0ADm6MJvAMwDx3YSPG8AZvMn8x3ACYbVaAL4gAukA">An Interactive Link To The Design</a></td></tr>
</tbody></table>
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I designed the Test Lead Rack with <a href="https://www.autodesk.com/products/fusion-360/overview">Fusion 360</a> as one of my efforts to learn this new (to me) software. I had been using <a href="https://www.sketchup.com/">Sketchup</a> for most of my previous projects, but the lure of P<a href="https://www.google.com/search?q=Parametric+Design">arametric Design</a> is to great to NOT switch to Fusion 360. Also, a lot of public available designed parts are available from Fusion 360.<br />
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Now 6.5 hours later after design, the 3D Printer provides the Results:<br />
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<div class="separator" style="clear: both; text-align: center;">
<a href="https://3.bp.blogspot.com/-04RMQxMXwN0/WsLua4kiN8I/AAAAAAAAN3s/mwjl3I1Qfv0TYWZxV9CgQ5CfMTzLnzhrgCKgBGAs/s1600/0402180907.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="900" data-original-width="1600" height="180" src="https://3.bp.blogspot.com/-04RMQxMXwN0/WsLua4kiN8I/AAAAAAAAN3s/mwjl3I1Qfv0TYWZxV9CgQ5CfMTzLnzhrgCKgBGAs/s320/0402180907.jpg" width="320" /></a></div>
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And now, it is in use:<br />
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<div class="separator" style="clear: both; text-align: center;">
<a href="https://1.bp.blogspot.com/-CNzIEbnoANA/WsLuidhOLkI/AAAAAAAAN3w/RkqBzEAOjho8d5MrC72a-a2Arbz5cnK5wCKgBGAs/s1600/0402181008.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="900" data-original-width="1600" height="180" src="https://1.bp.blogspot.com/-CNzIEbnoANA/WsLuidhOLkI/AAAAAAAAN3w/RkqBzEAOjho8d5MrC72a-a2Arbz5cnK5wCKgBGAs/s320/0402181008.jpg" width="320" /></a></div>
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-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
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<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-46301411125808832182018-01-07T11:23:00.000-08:002018-01-07T11:23:10.648-08:003D Printer - MY Noob Mistakes<br />
As posted before, I have been playing with a new TEVO Little Monster 3D Printer, I have made a LOT of Noob mistakes that could have been avoided if I had only knew.<br />
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<b>The following are notes to myself.</b><br />
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o. Do not turn off the power to the 3D Printer unless you are certain that the Hot-End has cooled down. if not, removing power to the 3D Printer will cause the filament to melt within the Cold-End and then a complicated repair method will be required to fix the problem.<br />
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o. Remember, 3D Printing is very SLOW, it is much slower than waiting for paint to dry.<br />
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o. Remember the hot-end is VERY HOT, I have several burns to remind me.<br />
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o. Learn how to set the Z zero Height to within a paper thickness of the print bed, or nothing will work correctly until you do, no mater how hard you try.<br />
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o. Buy several sets of Print Head replacement parts, for the; Cold-End, Thermal Break, and Hot-End.<br />
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o. Consider buying some <span style="background-color: white; color: #222222; font-family: "roboto" , "arial" , sans-serif; font-size: 16px;">Tetrahydrofuran (THF) </span>, it is the only effective thing that will dissolve PLA (for Hot-End clean and repair), and it can be used to glue PLA parts together. Or at least that is what google suggests.<br />
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o. Note, MOST often Hot-End repair work will be done while it is HOT (about 210 C, or more), other wise PLA will be hard and not easily removed.<br />
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o. For my use, Blue Painter Tape works best for the Printer Bed, it has some texture that will show up on the printed part, but PLA stick very good to it. A roles of Blue Painters Tape (10 inches wide) are available on-line for about $50, and worth every penny, it makes bed prep very easy.<br />
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o. If the Hot-End is disassembled, for cleaning or repair, remember it has to be re-assembled and tightened while at intended operating temperature, for me that is about 215C. If not, it WILL leak.<br />
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Note: I will add to this list as I learn more.<br />
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-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
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<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-70854815417473919602017-09-20T15:00:00.000-07:002017-09-20T15:00:32.812-07:00Reduction Gears<b>Sorry, this is not an Amateur Radio post.</b><br />
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After many months of working with a 3D Printer, I have finally successfully created a working set of interlocking reduction gears, each section provides a 7:1 reduction. This device is about 2 inches in diameter, the total reduction is 14:1.<br />
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The original <a href="https://www.thingiverse.com/thing:1410972">Ring Gear</a> from <a href="https://www.thingiverse.com/">Thingiverse</a> was modified to create this multi-stage Reduction Gear. My contribution was to modify it as necessary and join two sets together.<br />
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<a href="https://4.bp.blogspot.com/-iw11-uGQNuE/WcLfOKoCW2I/AAAAAAAAND8/aVa29QdTcZAqxh7XsQYtqNCOTRgdozA6QCKgBGAs/s1600/20170920_111141.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="900" data-original-width="1600" height="180" src="https://4.bp.blogspot.com/-iw11-uGQNuE/WcLfOKoCW2I/AAAAAAAAND8/aVa29QdTcZAqxh7XsQYtqNCOTRgdozA6QCKgBGAs/s320/20170920_111141.jpg" width="320" /></a></div>
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<tr><td style="text-align: center;"><a href="http://1.bp.blogspot.com/-akCHGGVieRo/WcLggqNK5HI/AAAAAAAANEQ/kATYyJpuaUMpSrHE8fy6--kX88YnRcz0QCK4BGAYYCw/s1600/photo_2017-09-19_12-01-04.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="320" src="https://1.bp.blogspot.com/-akCHGGVieRo/WcLggqNK5HI/AAAAAAAANEQ/kATYyJpuaUMpSrHE8fy6--kX88YnRcz0QCK4BGAYYCw/s320/photo_2017-09-19_12-01-04.jpg" width="316" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Sketchup Model</td></tr>
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The transfer plates (with the connecting pins) were assembled by adding the center HEX pin after printing. Each of the two Reduction Cluster were printer as an assembled single object on the printer. No cleanup or filing was necessary.<br />
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<a href="https://2.bp.blogspot.com/-Pa-HnJr-Mjk/WcLfUf2Y5CI/AAAAAAAANEA/VXHLTEmm6g4p7uwcVLP1wvTegXDYkGDcQCKgBGAs/s1600/20170920_111238.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="900" data-original-width="1600" height="180" src="https://2.bp.blogspot.com/-Pa-HnJr-Mjk/WcLfUf2Y5CI/AAAAAAAANEA/VXHLTEmm6g4p7uwcVLP1wvTegXDYkGDcQCKgBGAs/s320/20170920_111238.jpg" width="320" /></a></div>
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Silicon grease is used for lube.<br />
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I may increase the size (and with other modification) this could be used as a Light Weight Field Day Antenna Rotor.<br />
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-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
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<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-41330564495050360932017-05-03T16:37:00.001-07:002017-05-03T16:42:50.927-07:00Lost Friends<br />
This week has not been a good week, very sad, two of my Ham Radio Friends have passed away.<br />
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<a href="https://www.qrz.com/db/w7rdp">Doug Phillips - W7RDP</a> (SK) a good friend from the local Pacific QRP Group (pQRP).<br />
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<a href="https://www.qrz.com/db/w4LSC">Don Sehulster - K7QYP / W7LSC</a> (SK) - a very good <a href="http://wa0uwh.blogspot.com/2015/05/k7qyp-bit-of-history.html">Navy Buddy</a> (1968-1972).<br />
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73 - My Friends . . . K<br />
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-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
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<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-46223238954175945782017-04-30T20:58:00.001-07:002017-04-30T21:19:20.966-07:00First 3D PrinterI purchased a <a href="https://tevo3dprinterstore.com/products/2017-newest-tevo-delta-printing-area-d340xh500mm-openbuilds-extrusion-smoothieware-mks-tft28-bltouch-high-speed-3d-printer-kit">3D Printer</a>, and just now learning how to use it, there is a lot to learn.<br />
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After many trials and failures, I have successfully printed the equivalent of "<a href="https://en.wikipedia.org/wiki/%22Hello,_World!%22_program">Hello World</a>" for 3D Printers, which is the "<a href="http://www.3dbenchy.com/">3DBenchy</a>". This online part was designed to be a torture test for a 3D Printer, with many under-cuts, over-hangs and fills, that are somewhat difficult. This part is about 2.5 inches long.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://3.bp.blogspot.com/-tjmGFjtoeZk/WQapQ4ciwqI/AAAAAAAAL0E/2hb0d0B6Jj0k4A3p7z-S8ZnMJ1spkkxVgCKgB/s1600/20170430_201650.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="180" src="https://3.bp.blogspot.com/-tjmGFjtoeZk/WQapQ4ciwqI/AAAAAAAAL0E/2hb0d0B6Jj0k4A3p7z-S8ZnMJ1spkkxVgCKgB/s320/20170430_201650.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b>My Printed 3DBenchy Results</b></td></tr>
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3DBenchy was actually about my 10th attempt at print anything, the first few parts went horribly wrong.<br />
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Here are a few of my initial prints of a part of my own design, obviously I did not know what I was doing.<br />
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<a href="https://1.bp.blogspot.com/-IKfMvcgiTkg/WQaqE7AJw9I/AAAAAAAAL0U/4iQ-GdmxrK46aeqg-tvMlKJpmVQ4TjifACKgB/s1600/20170428_175641.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="180" src="https://1.bp.blogspot.com/-IKfMvcgiTkg/WQaqE7AJw9I/AAAAAAAAL0U/4iQ-GdmxrK46aeqg-tvMlKJpmVQ4TjifACKgB/s320/20170428_175641.jpg" width="320" /></a></div>
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Things got better with practice and understanding of the 3D Print process and control parameters.<br />
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<a href="https://4.bp.blogspot.com/-WoHQxzsikJI/WQaqU7ym5fI/AAAAAAAAL0g/N4tDqtdU8TIFUDdgE8eeDoVe004J7YYwACKgB/s1600/20170428_175746.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="180" src="https://4.bp.blogspot.com/-WoHQxzsikJI/WQaqU7ym5fI/AAAAAAAAL0g/N4tDqtdU8TIFUDdgE8eeDoVe004J7YYwACKgB/s320/20170428_175746.jpg" width="320" /></a></div>
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The above is a replacement part for an Orbital Sander, this part is no longer available from the manufacture, it will eventually be printed with Black ABS Plastic, which is similar to the original. I designed this part with <a href="https://www.freecadweb.org/">FreeCAD</a> and used <a href="http://slic3r.org/">Slic3r</a> for the G-Code output for the 3D Printer. For me, FreeCAD has a steep learning curve.<br />
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And, then . . .<br />
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On the next part, a Cable Chain of my own design, I must have lost the magic !!<br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj0fLtR7HFMshh5N5GnppY4Us5Kt7GrLD80JaIgfbKkFAIjaHrm8spioSlTcTlvVj-rKQP8rNzcbupxGcZ81L_MmBWpvIZS-7Sgp64nBmWX5l40B8p11ao5q2-v-ou4ld9doAQa5wxF_NAm/s1600/20170428_175848.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="180" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj0fLtR7HFMshh5N5GnppY4Us5Kt7GrLD80JaIgfbKkFAIjaHrm8spioSlTcTlvVj-rKQP8rNzcbupxGcZ81L_MmBWpvIZS-7Sgp64nBmWX5l40B8p11ao5q2-v-ou4ld9doAQa5wxF_NAm/s320/20170428_175848.jpg" width="320" /></a></div>
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But finally, things got better with practice.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://2.bp.blogspot.com/-B-Y-oCMAMv8/WQaq01n3-uI/AAAAAAAAL0s/7Wb2s0bKRdQujisyRQzyXMBpXTxITP8MACKgB/s1600/20170428_180100.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="180" src="https://2.bp.blogspot.com/-B-Y-oCMAMv8/WQaq01n3-uI/AAAAAAAAL0s/7Wb2s0bKRdQujisyRQzyXMBpXTxITP8MACKgB/s320/20170428_180100.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b>Cable Chain Links</b></td></tr>
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<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-4VVXFMgZLmM/WQaq5WNRx5I/AAAAAAAAL0w/cE2k-_lynyoSH3HA_GjO5a7g02Yf4-ifwCKgB/s1600/20170428_222816.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="180" src="https://1.bp.blogspot.com/-4VVXFMgZLmM/WQaq5WNRx5I/AAAAAAAAL0w/cE2k-_lynyoSH3HA_GjO5a7g02Yf4-ifwCKgB/s320/20170428_222816.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b>The First Two Links of a Cable Chain.</b></td></tr>
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I am currently printing four Cable Links with newer/better design, I will report the results. For these link design, I have used <a href="https://www.sketchup.com/">Sketchup</a> and <a href="http://slic3r.org/">Slic3r</a>. For simple designs Sketchup is easy to use, as long as you only need "Union" style of object creation, that is, objects that touch are automatically joined together (union'd) when exported as an STL file. STL files are needed by Slic3r.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://2.bp.blogspot.com/-HTcPq6L58Nc/WQa1JGEDOAI/AAAAAAAAL1k/MebH4DVWuL8EXHEtCauLqQScyY00n4kOACKgB/s1600/20170430_210929.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="180" src="https://2.bp.blogspot.com/-HTcPq6L58Nc/WQa1JGEDOAI/AAAAAAAAL1k/MebH4DVWuL8EXHEtCauLqQScyY00n4kOACKgB/s320/20170430_210929.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b>Four Cable Chain Links<br />About 2/3 Complete</b></td></tr>
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This is fun, I think I am going to enjoy my new 3D Printer.<br />
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-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
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<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-59899704996088796832017-03-07T17:53:00.001-08:002017-03-10T02:21:32.658-08:00Esp8266 WebServer Farm - AgainAfter several long months, I have reactivated my <b><a href="http://esp.wa0uwh.com:8154/">Esp8266 WebServer Farm</a></b>.<br />
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Use this links to all of my <a href="http://wa0uwh.blogspot.com/search/label/Esp8266">Esp8366</a> project blog posts.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://3.bp.blogspot.com/-4aIjgs9rPp8/VU1YsmbuAKI/AAAAAAAAHdg/LvIAwRIEuuUyli8stTnetCG4LGGufAT-QCPcB/s1600/20150508_171952.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="225" src="https://3.bp.blogspot.com/-4aIjgs9rPp8/VU1YsmbuAKI/AAAAAAAAHdg/LvIAwRIEuuUyli8stTnetCG4LGGufAT-QCPcB/s400/20150508_171952.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b>Esp8266 WebServer Farm</b></td></tr>
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Currently, one of my WebServers can be accessed as: <a href="http://esp.wa0uwh.com:8154/">http://esp.wa0uwh.com:8154</a><br />
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The main reason that it has be off-line, is lack of interest, and recently, I could only get the code to compile on the old Arduino IDE (Rev 1.6.x). The code is quite large and I took advantage of many "tabs" for code fragments, which are concatenated before presented to the compiler. The new Arduino IDE Revision (1.8.1) is much more strict regarding Header Files, code files, and program structure. There were just <b>TOO MANY</b> errors to correct to keep my interest in solving the problem.<br />
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Once started to solve the problems and not getting much accomplished, my Friend <b>Jeff - Ko7m</b>, suggest another IDE, he suggested "<a href="http://platformio.org/">PlatformIO IDE</a>".<br />
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With little work, I found and installed PlatformIO, but alas, I found similar problems and concerns with it. But little-by-little after much on-line reading, Jeff and I worked out the best file structures that worked with PlatformIO.<br />
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I have not moved the new code structure to GitHub, but maybe soon.<br />
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-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
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<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-31814766409059901422017-01-14T06:52:00.001-08:002017-01-14T22:50:16.664-08:00My Soldering TIP #1Several years ago my trusty Weller Soldering Iron failed, knowing that most of my projects were going to use small SMD parts, I ordered a fancy replacement, a Hakko FX-888 Soldering Station (about $90.00) with several assorted tips, some really small tips for SMDs. The tracking information, revealed that it would be in my hands in about three weeks.<br />
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But, I needed a replacement Iron NOW, to finish a project. I went to Frys, and found a cheapy Iron that I thought I could use (about $29.00), it was a Hakko Presto 980-V12/P. It had only one smallish chisel tip, but I thought it could be used for some larger SMDs.<br />
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Well, now several years later, the expensive Hakko FX-888 with its small tips is VERY seldom used (maybe about 3%), while the cheap Hakko Presto 980-V12/P is used for most (if not all) of my projects, and I am still using the original TIP. If you have seen my projects (typically on a 0.5in x 0.7in PCB boards) you might think the FX-888 would be more appropriate, but I fould it is not.<br />
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The following are some of my projects where the Hakko Presto 980-V12/P was used:<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://4.bp.blogspot.com/-ogj-i_ms6B8/T2FVcv-el6I/AAAAAAAAClA/sQA1pc0-x1IYPsO-VM_lJ8Nne82PRVYQQCPcB/s1600/IMAG0561.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="191" src="https://4.bp.blogspot.com/-ogj-i_ms6B8/T2FVcv-el6I/AAAAAAAAClA/sQA1pc0-x1IYPsO-VM_lJ8Nne82PRVYQQCPcB/s320/IMAG0561.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">HomeBrew Double Sided<br />
Si570 Board</td></tr>
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/--7TWppVdZ1w/U2Ku_P5Ir1I/AAAAAAAAGUM/hFOuOpTHJ0E5mpL02_SNH0BV1hcrSZIygCPcB/s1600/PowerReg01.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="240" src="https://1.bp.blogspot.com/--7TWppVdZ1w/U2Ku_P5Ir1I/AAAAAAAAGUM/hFOuOpTHJ0E5mpL02_SNH0BV1hcrSZIygCPcB/s320/PowerReg01.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">HomeBrew Double Sided Project<br />
These are 0805 Caps, and SOT-223 Voltage Reg</td></tr>
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I like and use the Hakko 980-V12/P, it has "Two Temps, 20W normal, and 130W push button switch", very seldom have I used the 130W button. <br />
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I have recently purchased a second Hakko 980-V12/P for my tool box.<br />
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Today I think the Hakko 980-V12/P is priced about $60.00, if you are interested in online purchase, google is your friend. see:<span style="background-color: white; color: #222222; font-family: "arial" , sans-serif; font-size: 12.8px;"> </span><a data-saferedirecturl="https://www.google.com/url?hl=en&q=https://www.google.com/search?q%3Dhakko%2B980&source=gmail&ust=1484459413896000&usg=AFQjCNFmsUBpsIpgW0BNRFkifabF3cNcHA" href="https://www.google.com/search?q=hakko+980" style="color: #1155cc; font-family: arial, sans-serif; font-size: 12.8px;" target="_blank">https://www.google.com/<wbr></wbr>search?q=hakko+980</a><br />
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I think you will like it.<br />
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BTW: I use a "wall outlet timer" to supply power to my soldering irons, if I forget, the timer turns off power to them after about 45 minutes, which saves the soldering TIPs.<br />
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-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
<br />
<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-19133796230380359152016-12-07T16:23:00.001-08:002016-12-08T23:24:02.269-08:00A Small Experimental Receiver CircuitI have finally found some time to "<b>melt some solder</b>" at my new location and new eShop bench. The bench is not finished yet, but I needed a <b>Solder FIX</b>.<br />
<br />
This, like all of my project, is an attempt to make projects as small as my abilities allow.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://2.bp.blogspot.com/-ElgOi0rWwZw/WEieX2ed-SI/AAAAAAAALTc/dA64NMHSO_M4kNtRHr2rebsO1POzLYByQCKgB/s1600/20161207_140206.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="225" src="https://2.bp.blogspot.com/-ElgOi0rWwZw/WEieX2ed-SI/AAAAAAAALTc/dA64NMHSO_M4kNtRHr2rebsO1POzLYByQCKgB/s400/20161207_140206.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">New eShop Bench</td></tr>
</tbody></table>
The project that I am working on is some boards I just received back from OSH Park. The boards are a small and part of an experimental HF Receiver. The boards edge connectors are "Castellated" to allow them to be used within a larger PCB circuit, and with attached Headers, they can be used with/on a Solderless Proto Board.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://3.bp.blogspot.com/-zg3L6VGuops/WEie7pzPNDI/AAAAAAAALTg/jaOSb71m_B0vEdXz9r-qMR-REfGN77DaACKgB/s1600/20161207_135723.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="225" src="https://3.bp.blogspot.com/-zg3L6VGuops/WEie7pzPNDI/AAAAAAAALTg/jaOSb71m_B0vEdXz9r-qMR-REfGN77DaACKgB/s400/20161207_135723.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">The size of these boards are:<br />
Left: 0.8x1.0 inch,<br />
Right: 0.5x1.0 inch</td></tr>
</tbody></table>
<br />
This is my experimental design, it is a circuit that contain the: HF VFO Mixer, Band Pass Filter (BPF, 40MHz), and BFO Mixer.<br />
<br />
The bigger boards on the left are similar to those on the right, except they also contains the Oscillators for both the VFO and the BFO, along with the voltage regulator for the oscillator chip.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-R65CRJhcs9w/WEijTQe4GMI/AAAAAAAALTo/lBIGEmxUlJw1BcbyqxxwFv4FBrL3WCoRQCKgB/s1600/20161207_135821.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="225" src="https://1.bp.blogspot.com/-R65CRJhcs9w/WEijTQe4GMI/AAAAAAAALTo/lBIGEmxUlJw1BcbyqxxwFv4FBrL3WCoRQCKgB/s400/20161207_135821.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">The components on the lower half are installed<br />
Ready for some testing<br />
Unpopulated is the VFO/BFO and Voltage Regulator</td></tr>
</tbody></table>
LTSpice suggests this circuit will work, but assessing the actual performance is the real reason for building this experimental circuit.<br />
<br />
Additional circuits will be needed, to make this a real receiver, like: Band Select Filters, Automatic Gain Control, Audio Circuit, a Microcontroller, and Display. Likewise, I will make each as small as I can.<br />
<br />
Testing will start when I have some (more) time.<br />
<br />
<br />
-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
<br />
<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-22157290583119424382016-11-20T22:39:00.001-08:002016-11-21T13:16:56.289-08:00My new eShop<b>UPDATED: 11/21/2016</b><br />
<br />
I have NOT posted anything for several (6) months, my life has been in somewhat of turmoil (maybe, I am getting too old for this), but now, maybe things are starting to get back to normal.<br />
<br />
Regardless, I have been thinking of many HomeBrew projects that I want to build and blog. But first I have to set up my eShop in this new (and better) location.<br />
<br />
This is the beginnings of my new eShop setup:<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiwsqyO8iLJL3ZnSDWTWONB-CVebvIOOPKIwweRHZ511e5AQsCcLExT642qsBv0ap-KsWsYBOovBmXA_1V37P0englmuiG0XmTbk8q8JtkBcJan9lOQr3Z_H6gH-HN9y6SUtcPXXK3sz-H2/s1600/20161119_171017.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="225" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiwsqyO8iLJL3ZnSDWTWONB-CVebvIOOPKIwweRHZ511e5AQsCcLExT642qsBv0ap-KsWsYBOovBmXA_1V37P0englmuiG0XmTbk8q8JtkBcJan9lOQr3Z_H6gH-HN9y6SUtcPXXK3sz-H2/s400/20161119_171017.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">My new eShop Bench</td></tr>
</tbody></table>
I just finished building the wooden shelves. My previous eShop shelves were about the same but fixed, these shelves are movable, and therefore this setup should be more effective for varying sized electronic equipment.<br />
<br />
Adjacent to that, is my current MS 10 WorkStation, Raspberry Pi, and Orange Pi set ups:<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-U1e4p68na3o/WDKQdE9R3-I/AAAAAAAALQ8/mHZrS7ritkUD6ogzxeZ57PBD0N_QHMmGwCKgB/s1600/20161119_171220.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="225" src="https://1.bp.blogspot.com/-U1e4p68na3o/WDKQdE9R3-I/AAAAAAAALQ8/mHZrS7ritkUD6ogzxeZ57PBD0N_QHMmGwCKgB/s400/20161119_171220.jpg" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Computer Workstation</td></tr>
</tbody></table>
The three bottom screens are connected to the MS WorkStation, and the three uppers are for the PI's.<br />
<br />
Note: and the refrigerator is only about 15 feet away, hihi.<br />
<br />
Unfortunately, I have not started my Ham Station and Antenna System yet.<br />
<br />
I have some small Ham Radio related PC boards out for manufacturing at OSH Park, if they works as expected, I may be blogging about those, soon.<br />
<br />
<b>UPDATE:</b><br />
<b><br /></b>
The day after installing my shelves and turning on the Oscope for the first time in a long while, the (calibration) trace is going bonkers, with a short bright spot at the beginning of the trace. Trace INTEN has little control. DANG, now something else to repair.<br />
-<br />
<pre></pre>
Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com1tag:blogger.com,1999:blog-7396057548824140336.post-33636052249461069012016-05-03T23:19:00.000-07:002016-12-19T14:14:07.793-08:00FORD Rant - Oil Cooler Bypass Valve - is a non replaceable part.<b>UPDATED: Tue May 17 11:19:46 PDT 2016</b><br />
<br />
This is post not about Electronics, it is a RANT about FORD.<br />
<br />
For the last few weeks, my Son and I have been working on his F350 6.0L Diesel Engine, to replace; the Exhaust Gas Recirculation (EGR) Heat Exchanger, and the Oil Cooler. This work is a pain because most of the top of the engine, including the Turbo Charger has to be removed to get to the parts being replaced. There are several good Youtube video showing the details.<br />
<br />
We ordered parts and gaskets bases on information available. This repair is somewhat of a difficult task due to engine compartment large size and the long reaches necessary to access everything. There is one very dirty mess when the Oil Cooler cover is removed, where about a quart of oil spills over the engine valley, but that cleanup marked the beginning of the actual part replacement and rebuild.<br />
<br />
Most of the previously dis-assembled parts where replaced in the order they were removed without difficulty.<br />
<br />
<b>But Then</b><br />
<br />
<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: right; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://4.bp.blogspot.com/-oTNXmh2W7Gk/VymOEsx5zbI/AAAAAAAAKZA/rKcFMDyLeS47GQJgkj0VNaNdTD2aVoPSgCKgB/s1600/20160422_125111.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="180" src="https://4.bp.blogspot.com/-oTNXmh2W7Gk/VymOEsx5zbI/AAAAAAAAKZA/rKcFMDyLeS47GQJgkj0VNaNdTD2aVoPSgCKgB/s320/20160422_125111.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b>FORD Failed<br />Oil Drain Back and Oil Cooler Bypass Valve Assemble</b></td></tr>
</tbody></table>
On top of the Oil Cooler Cover there is a small assemble which is held in place with two screws within the Oil Filter Case (Can). This small assemble is about 3 inches wide.<br />
<br />
This small assemble holds two valves; one to Drain Back oil from the Oil Filter Case (helpful during oil and filter changes), and the other is the Oil Cooler Bypass Value (OCBV) which opens in case the Oil Cooler get clogged up. These two valves are very simple; the first is held shut by gravity and can pressure; the other is a spring loaded Brass Plunger with a small flat plastic/rubber (of some sort) washer (flapper) that opens at 25lbs of Oil Cooler pressure.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://4.bp.blogspot.com/-Z_hOblwvINg/VymOvXcytkI/AAAAAAAAKZE/yCpfE9qCPk8UsokZDh59nhPISWvORndDwCLcB/s1600/20160422_124510.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="180" src="https://4.bp.blogspot.com/-Z_hOblwvINg/VymOvXcytkI/AAAAAAAAKZE/yCpfE9qCPk8UsokZDh59nhPISWvORndDwCLcB/s320/20160422_124510.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b>Spring Loaded Oil Cooler Bypass Value<br />The Brass Plunger shows scoring</b></td></tr>
</tbody></table>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://4.bp.blogspot.com/-TN4TE4yVCac/VymO_w8ewLI/AAAAAAAAKZM/waI_cKhF2tUWRm7ny-B8Rxl92XDtPhEmQCLcB/s1600/20160422_125035.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="180" src="https://4.bp.blogspot.com/-TN4TE4yVCac/VymO_w8ewLI/AAAAAAAAKZM/waI_cKhF2tUWRm7ny-B8Rxl92XDtPhEmQCLcB/s320/20160422_125035.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b>The Wood Chip holds open the washer at the failure.</b></td></tr>
</tbody></table>
<br />
<br />
<b>The Problem</b><br />
<br />
According to <b>FORD</b>, these two small values are <b>NOT</b> replaceable parts !!<br />
<br />
And therefore, normal Auto Parts stores do not have the parts, nor does FORD.<br />
<br />
Our OCBV plastic/rubber seal is damaged, and the Brass Plunger is scored showing that it had failed long ago.<br />
<div class="separator" style="clear: both; text-align: center;">
</div>
<br />
The values can only be replaced with a NEW Oil Cooler Cover, which is about $180.00, the plastic/rubber part, if available, should only cost about $2.00, even though it is about $0.10 worth of plastic/rubber.<br />
<br />
<b>My Conjecture</b><br />
<br />
I suspect that the OCBV failure contributed to the EGR Cooler failure and therefore the need to repair this engine - it is a $0.10 part ?<br />
<br />
<b>Our Planned Fix</b><br />
<br />
Google searches provided very little help or suggestions of a solution.<br />
<br />
Our current plan is to create a new Teflon washer (value flapper). A Teflon rod is now on order. Experiments with different on-hand materials failed to hold up in a gas/oil environment. Teflon appears to have the right properties; inert and high temperature resistant.<br />
<br />
Thanks FORD, my Son's truck has be on blocks for about three weeks now, while finding a workable solution.<br />
<br />
<b>End Rant</b><br />
<br />
If this works as planned, I will be selling Teflon washer, and or Teflon Plunger with integrated Teflon Value seat, . . . soon :-).<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://4.bp.blogspot.com/-ZD-Thjj6wPA/V1b59YEq37I/AAAAAAAAKn4/ChsEKNf1FjELusN5VGvO-3oUtYlo8R61ACKgB/s1600/20160601_172012.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" height="180" src="https://4.bp.blogspot.com/-ZD-Thjj6wPA/V1b59YEq37I/AAAAAAAAKn4/ChsEKNf1FjELusN5VGvO-3oUtYlo8R61ACKgB/s320/20160601_172012.jpg" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><b>Teflon Washer</b></td></tr>
</tbody></table>
<b>Update:</b><br />
The engine has now been running with the new Teflon Value Seat for several weeks, when the oil is changed it will be removed and inspected for ware.<br />
<br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://3.bp.blogspot.com/-JXbmlMpoeno/V193eEFr3UI/AAAAAAAAKr0/7j5zqR1I_fwLgkj5nWfqJUm0uFtmvFQQQCKgB/s1600/20160505_171418.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" src="https://3.bp.blogspot.com/-JXbmlMpoeno/V193eEFr3UI/AAAAAAAAKr0/7j5zqR1I_fwLgkj5nWfqJUm0uFtmvFQQQCKgB/s320/20160505_171418.jpg" width="180" /></a></div>
Here is a photo of the Bypass Valve Assembly reinstalled ( I had forgotten I took this photo). The Oil Filter Tower and Canister have not been reinstall yet, as can be seen, two screws hold the assembly in place. Inspection for ware at the next oil change, will be easy.<br />
<br />
<br />
-<br />
<br />
-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
<br />
<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com1tag:blogger.com,1999:blog-7396057548824140336.post-78978162229265196842016-02-01T11:38:00.001-08:002016-04-14T13:34:06.964-07:00ASCII Strings within the Largest Known Prime Number<br />
Someone on the <a href="https://www.youtube.com/watch?v=jNXAMBvYe-Y">Youtube Numberphile Channel</a> was wondering if after converting the Largest Prime Number to base 26 (see previous post) would there be any interesting ASCII strings within the Number.<br />
<br />
I think I have created a Unix Function that will do the conversion.<br />
<br />
( echo "obase=16;"; echo "obase=26; 2^74207281-1" | bc | tr -d '\n\\' | sed 's/ /;65+/g' ) | bc | xxd -r -p<br />
<br />
This will take a while (maybe several hours, or days), but if I find something interesting, I will report the results.<br />
<br />
<br />
-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com1tag:blogger.com,1999:blog-7396057548824140336.post-17298538135691615722016-01-22T22:20:00.004-08:002016-02-01T00:48:28.085-08:00The New Largest Prime Number Found<b>UPDATED:</b><br />
Added Details and Links<br />
<br />
Recently (Jan 7. 2016) the next and Largest Prime Number has be found (so far), it has about 22 Million Digits long, See, YouTube at: <a href="https://goo.gl/C7ngE7">https://goo.gl/C7ngE7</a>.<br />
<br />
The number can be expressed as a small-simple math function, that is: "<b>2^74207281-1</b>"<br />
<br />
The previous Large Prime Number (17 Million Digits) was found about 3 years ago on Jan 25, 2013, see: <a href="http://goo.gl/UbAWK0">http://goo.gl/UbAWK0</a><br />
<br />
Hopefully, and if history hold true, we will see the next Largest Prime sometime within the next 3 to 5 years.<br />
<br />
Just for fun, I decided to see how long it would take my 3.4GHz Workstation to perform the calculation and print the full 22 Million Digits to the screen - it took about 154 minutes - it was like watching paint dry. :-)<br />
<br />
Note: To verify that it "<b>is actually prime</b>" would probably take several months (<strike>or more</strike> actually several years) on my computer.<br />
<br />
Here is the linux command that I used to print this New Prime, and a few of the Beginning and Ending Digits of the results:
<br />
<br />
<pre><code>
$ time echo "2^74207281-1" | bc
30037641808460618205298609835916605005687586303030148484394169334554
77232190679942968936553007726883204482148823994267278352907009048364
32218015348199652241372287684310213386284573666361506667532122772859
35986405778025687564779586583214205117110963584426293657265038724071
.
. ( 22 Million More Digits )
.
74801792765597096176486305356033886997788467889060830923906229428002
87770846681535011427622921221836904045477963931367013401448014940470
41169663347456468851607177740147629124621136468794258014451073931002
12927181629335931494239018213879217671164956287190498687010073391086
436351
real 153m50.931s
user 92m34.588s
sys 0m13.496s
</code></pre>
<br />
Note: To capture the number on the screen, a large display buffer of more than 22 Meg Bytes (of RAM) was necessary.<br />
<br />
I need to check with YouTube and/or Numberphile to see if my calculated number is correct :-)<br />
<br />
My computer is current checking four large numbers to see if they are Prime, this consumes about 100% of the Quad Core CPU, but it runs at a very low priority so it does not effect my use of the computer. Each is expected to finish at different times, Below shows the number being tested, and number of days until I should have the results:<br />
<ul>
<li>2^<a href="http://www.mersenne.org/M332338003">332,338,003</a>-1, results expected in 643 days</li>
<li>2^<a href="http://www.mersenne.org/M332338319">332,338,319</a>-1, results expected in 643 days</li>
<li>2^<a href="http://www.mersenne.org/M332338397">332,338,397</a>-1, results expected in 858days</li>
<li>2^<a href="http://www.mersenne.org/M332338777">332,338,777</a>-1, results expected in 858 days</li>
</ul>
<div>
As you may have expected, . . . I am a fan of Very Large Numbers !<br />
<br />
-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
<br /></div>
Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-28429183076630217362016-01-21T15:27:00.000-08:002016-01-23T07:39:58.916-08:00Simple Complexity - By Proxy<b><a href="http://wa0uwh.blogspot.com/2016/01/simple-complexity-by-proxy.html">UPDATED:</a></b><br />
Added Details and Links<br />
<br />
For sometime I have struggled with how to allow public access to my home web servers and Esp8266 modules without opening up my network to abuse. In the past I have managed public access via my Router, by changing its configuration of Port Forwarding and NAT. This works, but it is a pain to manage and generally requiring a re-boot of the network for each change.<br />
<br />
Recently, I have discovered (actually re-discovered) that an Apache2 Web Proxy Server is much easier to manage, but it has a bit of a steep learning curve, with a lot of manual pages to read. One key concept is that Apache2 <b>ReWriteRules</b> are a super-set of the functionality of <b>ProxyPass</b>, each have their own documentation web pages.<br />
<br />
<b>After building the Required Config files</b><br />
<br />
Now, on my Router I allow only Ports: <b>http 80</b>, <b>8040</b>, <b>8160</b>, and a private <b>ssh</b> port for access from the Internet. Ports <b>8040</b>, and <b>8160</b> are still open for historical reasons, that is, they are used for my published Web Pages at: <a href="http://www.wa0uwh.com:8040/">http://www.WA0UWH.com:8040</a>, and my Esp8266 Server Farm devices.<br />
<br />
The Apache2 Web Server supports: <b>Virtual Host Names</b> with <b>Proxy Redirects</b>, <b>ReWriteRules</b>, and <b>ProxPass</b>. By setting up "<b>*.wa0uwh.com</b>" as a CNAME (an aliases) to "<b>www.wa0uwh.com</b>" at my DNS Provider, I can use any "device name" I would like in the config files to initiate a proxy process. For example: I can now use and publish "<a href="http://node129.wa0uwh.com/"><b>http://node129.wa0uwh.com</b></a>" for one of my <b>Esp8266 Web Server</b> modules. The actual connection details and security are all hidden behind the proxy curtains.<br />
<br />
The normal web page <b>port 80</b> is setup with a default virtual host page of; "<b>Error 404</b>", only configured <b>virtual hosts</b> and <b>named devices</b> are let through the proxy.<br />
<br />
Note: The service and/or host that is selected is a combination of both Port Number and Host Name (or alias). For an incoming connection, the file is scanned from top to bottom, only the first match is used to select the service.<br />
<br />
The following are excerpts from my Apache2 Default Virtual Host configuration file.<br />
<pre><code>
ServerName default.wa0uwh.com
LogLevel alert rewrite:trace1
<VirtualHost *:80>
ServerAdmin webmaster@localhost
DocumentRoot /var/www/DEFAULT/Public
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>
# End
</code></pre>
<br />
The following are excerpts from my Apache2 Named Virtual Host configuration file.<br />
<pre><code>
## Main Web Pages
## Loft Raspberry PI
<VirtualHost *:8040 *:80 >
ServerName rp21.wa0uwh.com
RewriteEngine on
ServerSignature Off
RewriteRule /(.*)$ http://192.168.___.___/$1 [P,L]
</VirtualHost
## Loft Raspberry PI
<VirtualHost *:8040 *:80 >
ServerName rp22.wa0uwh.com
RewriteEngine on
ServerSignature Off
RewriteRule /(.*)$ http://192.168.___.___/$1 [P,L]
</VirtualHost>
# Esp8266 Node on Published Port 8160
<VirtualHost *:8160 >
ServerName node.wa0uwh.com
ServerAlias node*.wa0uwh.*
ServerAlias localhost
RewriteEngine on
RewriteRule /(.*)$ http://192.168.___.___/$1 [P,L]
</VirtualHost>
## Loft Esp8266 Nodes
<VirtualHost *:8040 *:80 >
ServerName node.wa0uwh.com
ServerAlias node*.wa0uwh.com
RewriteEngine on
ServerSignature Off
RewriteCond %{HTTP_HOST} ^node(129|162|164|168|169|170|172)\.wa0uwh\.com [NC]
RewriteRule /(.*)$ http://192.168.___.%1/$1 [P,L]
RewriteRule /(.*)$ - [R=404,L]
</VirtualHost>
## Loft WA0UWH Web Server
<VirtualHost *:8040 *:80>
ServerName www.wa0uwh.com
ServerAlias *.wa0uwh.com
ServerAlias localhost 192.168.__.__
DocumentRoot /var/www/WA0UWH/Public
Alias /gallery /var/www/WA0UWH/Public/Gallery
</VirtualHost>
# End
</code></pre>
<br />
<b>Note</b>, the above is just an excerpt from my Apache2 Virtual Host config file. For security reasons, the details; actual IPA's (___), BlackListing, Hacker Traps, Web Abuse Traps, and HoneyPots, are NOT included . Google is your friend for suggested configurations.<br />
<br />
Now, with simple edits of the Apache2 Virtual Host config file, I can turn <b>ON</b> or <b>OFF</b>, devices and/or services as desired, while leaving only the <b>http</b> and <b>ssh</b> ports open for public access at the router.<br />
<br />
Also note: each of my Raspberry PI Web Servers also have similar Apache2 Virtual Host config files, that is: Proxies are serving Proxies, and most often the actual destination is at different physical locations, and on different Networks! All unseen for my Internet users.<br />
<br />
<br />
-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a>Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com1tag:blogger.com,1999:blog-7396057548824140336.post-12081157033895860442015-12-14T21:46:00.001-08:002015-12-20T13:27:16.744-08:00Got a Round TUIT<b>UPDATED:</b><br />
<br />
As <a href="http://wa0uwh.blogspot.com/2015/12/some-antenna-work-and-repair_13.html">previously</a> posted, I just needed a <b>Round TUIT</b>.<br />
<br />
I receive the replacement CDSH270 Diodes for my Antenna Tuner today, with a little work and with a TUIT they were installed. The Tuner now works as before.<br />
<br />
While during the surgery on the tuner, I installed some sharp pointed spark gaps at the SO-239 connectors, and between the Balanced Line Terminals. Maybe they will help save the Diodes the next time I forget to disconnect the Antenna during the an Electric Storm.<br />
<br />
For the spark gaps, I soldered one end of a heavy copper wire directly to the SO-239 RF center connector, and then bolted the other end directly to ground (at the connector mount point). After the "Short" was installed, I cut it at the center with dull side-cutters, leaving sharp points on each side. The gap was adjusted to about 1/20 of a inch. The same was done between the Balanced Terminals.<br />
<br />
With another TUIT, I installed a 6 AWG ground wire to the Tuner, but waiting for a large spade lug to make the final connection. My available lugs are not big enough for 6 AWG.<br />
<br />
<br />
Today was nice and sunny, so I also raised the Long Wire Antenna to it normal height. Yesterday when I was repairing it, it was too cold and wet to futz with it to bring it to full height at 90 feet AGL.<br />
<br />
Two years ago I tried to work on the antenna, but could not get the 3/32 support line to slide back down the tree. I suspected it had "grown" into a limb, or was pitched into a warren slot. My friend <b>Jeff - KO7M</b> and I was able to pull together hard enough to finally break it free. To avoid the same problem again, I slipped the line into a 20 foot piece of 1/4 inch polypropylene ice-make tube. which we pulled up into the tree where the support line goes over the branches. Now two years later the line was easy to pull down and then back up.<br />
<br />
So far I have made a few SSB contacts with the current antenna configuration. Now I am anxious to work some WSPR - but another TUIT is in the way.<br />
<br />
-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
<br />
<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-75122304749312435232015-12-13T15:00:00.003-08:002015-12-22T21:40:14.689-08:00Some Antenna Work and Repair<b><a href="http://wa0uwh.blogspot.com/2015/12/some-antenna-work-and-repair_13.html">UPDATED:</a> </b>Tue Dec 22 21:38:59 PST 2015<br />
<br />
I removed the 9:1 BalBal from my Off-Center-Fed Long Wire Antenna, as described below, it did not work as well as expected. More testing and measurement needed.<br />
<br />
<hr />
<br />
There has been a lot of chatter on the local <a href="http://groups.yahoo.com/group/pQRP/">Yahoo pQRP</a> email list about building some <b>9:1 Unun</b>s as a group project. I already have the Toroids and Wire and had planned to make several of my own - I was just waiting for a <a href="https://www.google.com/search?q=round+toit">Round-TUIT</a> (TUIT).<br />
<br />
For the last several (6 or so) years, I have been using a 300 foot Off-Center-Fed (OCF) Long Wire antenna. It is strung up near the top of some nice tall trees with the feed point at about 90 feet AGL. It has worked very well on all bands for WSPR, QRSS, CW, and general Ham use. The antenna is fed with 450 ohm ladder line fed from a Tuner with an internal Balun. I rarely have to provide much <b>L</b> or <b>C</b> adjustment for reasonable performance.<br />
<br />
With a crippled antenna (see below), last night I worked <b>Sandy - KG7FFP</b> as she is new <b>General License</b> Ham - Good going Sandy! We were on 80m, 3.885MHz.<br />
<br />
There are several things that I have wanted to try, to see if I could improve performance.<br />
<br />
The first, is a no-brainer; <b>Ground the Tuner and the Rig</b>, something that has always been waiting for another <b>TUIT</b>.<br />
<br />
The second, may be more controversial, I have wanted to put a 9:1 BalBal at the feed point of the OCF Long Wire. With 450 ohms ladder line in, the output should approximate 4050 ohms, which I think would more closely match typical OCF Long Wire feed impedance. In my case the short end of the Long Wire is about 20 feet. The Feed Line drops straight into my Loft's window, across the celling to the Ham Rig, I think more impedance is desirable, in reality, I thing everything in close proximity becomes the antenna, that is; the long wire, feed line, metal roof, and the moss soaked wet-trees, and I don't think they are typically just 450 ohms :-)<br />
<br />
Another "nit" that I wanted to improve (or remove) is the "egg" insulator at the feed point. I have never really liked this centre point set up, but it is what I had when it was first installed. The new set up is a now a 14 inch long, 3/4 inch PVC (conduit) with three holes in each end. The antenna wire goes through a "<b>Z</b>" bend at each end of the conduit, then "<b>V</b>'s" down to my new 9:1 BalBal, which is about 18 inch lower. The antenna wire is standard, solid copper 12 AWG conduit wire.<br />
<br />
My antenna tuner is still in my eShop waiting replacement diodes (<a href="http://www.mouser.com/search/ProductDetail.aspx?R=0virtualkey0virtualkeyCDSH270">CDSH270</a>), they are on order and should arrive soon. The antenna and Tuner took a near hit during one of the last electric storms. I was near the radio and heard a snap or spark across the terminals or somewhere inside, the radio did not suffer any ill effects, the tuner TOOK it ALL.<br />
<br />
So, now what?<br />
<br />
My newly configured OCF Long Wire Antenna is now up and ready for use, but still waiting tuner repair.<br />
<br />
I am expecting some <b>VERY GOOD</b> to <b>EXCELLENT</b> performance from this antenna configuration, because it was installed <b>exactly</b> as per the <b>weather-man specification</b> - that is, it was raining all the time I was outside working with; support lines, antenna wire, BalBal, and feed line. I got soaked ! Everyone knows, that the best antennas always go up during inclement weather.<br />
<br />
But, time will tell, I will post my impressions, measurement, and results, when available.<br />
<br />
<br />
-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
<br />
<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-32475615140144328852015-12-12T16:03:00.000-08:002015-12-12T17:55:04.520-08:00More Fun with Cyclops Numbers<a href="http://wa0uwh.blogspot.com/2015/12/more-fun-with-cyclops-numbers.html"><b>UPDATED:</b></a><br />
Added Details and Links<br />
<br />
<br />
I created a fun function to compute <b>Cyclops Numbers</b>, see <a href="http://wa0uwh.blogspot.com/2015/12/large-numbers.html">previous</a> post.<br />
<br />
<b><br /></b>
<br />
<div style="text-align: center;">
<b>D=9; C=0; L=27; </b></div>
<div style="text-align: center;">
<b>echo "obase=${D}+1;(${D}+1)^(2*${L}-1) -1 -(${D}-(${C}%${D}))*(${D}+1)^(${L}-1)" | bc</b></div>
<br />
Where:<br />
<ul>
<li><b>D</b> = Is the side Digits, <b>1</b> to <b>9</b></li>
<li><b>C</b> = Is the single Cyclops Eye Digit, must be < <b>D</b>, or <b>C mod D</b> will be used</li>
<li><b>L</b> = The Cyclops Eye Location (width)</li>
</ul>
<br />
D=8; C=3; L=2; => <b>838</b><br />
D=8; C=3; L=3; => <b>88388</b><br />
D=8; C=3; L=4; => <b>8883888</b><br />
D=4; C=8; L=5; => <b>444484444</b><br />
D=9; C=0; L=6; => <b>99999099999</b> <br />
<br />
The results for the above function: <br />
<div style="text-align: center;">
<b><br />99999999999999999999999999099999999999999999999999999</b></div>
<br />
<br />
It is all fun and games, until someone pokes the Cyclops Eye :-)<br />
<br />
<br />
-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
<br />
<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com2tag:blogger.com,1999:blog-7396057548824140336.post-23226165970657018242015-12-09T14:09:00.000-08:002016-01-22T17:34:11.954-08:00More Large Numbers<a href="http://wa0uwh.blogspot.com/2015/12/more-large-numbers.html"><b>UPDATED:</b></a><br />
Added Details and Links<br />
<br />
<b>Update: Jan 7, 2016</b> - New Largest Prime found: <b>echo "2^74207281-1" | bc</b>, which is 22 Million Digits, the function takes 77.25 minutes to compute on a 3.4GHz Processor. See, youtube at: <a href="https://goo.gl/C7ngE7">https://goo.gl/C7ngE7</a><br />
<br />
See <a href="http://wa0uwh.blogspot.com/2015/12/large-numbers.html">previous</a> post.<br />
<br />
The <a href="https://primes.utm.edu/largest.html">largest known</a> prime number is: 17,425,170 digits long, it can be computed with this very short function:<br />
<br />
<div style="text-align: center;">
<b>echo "2^57885161 -1" | bc</b></div>
<br />
On my Workstation (2.2GHz) it takes about 82 minutes to compute, but with more than 17M digits, it takes much longer to display or print.<br />
<br />
To print, it would require 7.7 Reams of paper; single sided, 80 character per line, 56 lines to a page, and 500 pages pre ream.<br />
<br />
Note: The person that finds the "<b>next</b>" larger prime number will be famous.<br />
<br />
<br />
-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
<br />
<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-89405373051634172192015-12-09T08:26:00.000-08:002015-12-09T09:11:00.682-08:00Large Numbers<b><a href="http://wa0uwh.blogspot.com/2015/12/large-numbers.html">UPDATED:</a></b><br />
Added Details and LInks<br />
<br />
As noted in previous posts, I am a fan of Large Numbers, I am especially interested in small functions that compute Large Numbers.<br />
<br />
Recently I watched a Numberphile <a href="https://www.youtube.com/watch?v=HPfAnX5blO0">Youtube</a> video, which captivated my interest. The numbers that I found most interesting are large "Cyclops Numbers".<br />
<br />
The following Linux function will compute a large Cyclops:<br />
<br />
<div style="text-align: center;">
<b>echo "10^(2*253-1) -1 -9*10^(253-1)" | bc</b> </div>
<br />
Can you spot the Cyclops Eye?<br />
<br />
<br />
99999999999999999999999999999999999999999999999999999999999999999999\<br />
99999999999999999999999999999999999999999999999999999999999999999999\<br />
99999999999999999999999999999999999999999999999999999999999999999999\<br />
99999999999999999999999999999999999999999999999909999999999999999999\<br />
99999999999999999999999999999999999999999999999999999999999999999999\<br />
99999999999999999999999999999999999999999999999999999999999999999999\<br />
99999999999999999999999999999999999999999999999999999999999999999999\<br />
99999999999999999999999999999<br />
<br />
<br />
-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
<br />
<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0tag:blogger.com,1999:blog-7396057548824140336.post-54642201535562024462015-12-08T10:21:00.001-08:002015-12-12T20:57:22.556-08:00Email from Raspberry PI or the Esp8266<b><a href="http://wa0uwh.blogspot.com/2015/12/email-from-raspberry-pi-or-esp8266.html">UPDATED:</a></b><br />
Added Details and Links<br />
<br />
If you have been following my recent blog post, I posted about using "<b>curl</b>" to send SMS messages to a Cell Phone Number, I have also created a software function to send a similar SMS messages from Esp8266, and/or using the same strategy this could be used on a Raspberry PI. The SMS messages are transferred to the "<a href="http://textbelt.com/">textbelt.com</a>" Open SMS Gateway. Access is via a HTML URL post, or via a command line "curl" command which simulates a HTTP post. The textbelt.com server imposes some limits, that is; no more than 3 messages per 3 minutes, and no more than 75 messages per day from a single IPA.<br />
<br />
The folks at Textbelt are gracious to allow us "small-time" users to access their gateway for FREE, - SPAMMERS are not welcome.<br />
<br />
But, if you want your Raspberry PI or Esp8266 to send an actual "email", that is another problem. Accessing an "Open" <b>Simple Mail Transport Protocol Gateways</b> (an SMTP) is normally a problem for most users. The reason an "Open" SMTP is desirable for our Internet-of-Things (IoT's) is that authentication is NOT required on Open SMTP's, and therefore there is NO need for a "clear text" password saved in a file, nor is it transferred over the Internet.<br />
<br />
There are a few Open SMTP available, where services are purchased by SPAMMERS to do their thing. A few of these SMTP gateways allow low-volume users access to their services for FREE, with some restrictions. I have tried several Open SMTP gateways, and found most have additional requirements that I did not agree, like; sign up with a credit card.<br />
<br />
I am currently using "<a href="http://smtp2go.com/">smtp2go.com</a>" which has a FREE Option and does not require a credit card to sign up. For low volume users like myself, it has a limit of 25 emails per hour, and/or 1000 emails per month, - which is more than enough email for my IoT's to report status, and/or other reports to me via email.<br />
<br />
I have implemented a Mail Transfer Agent (MTA) which "talks" to the Open SMTP to send my messages. Messages can be sent to my normal Gmail Account, or to my Cell Phone as an SMS text message, or to any other email address that I desire.<br />
<br />
I have written complete MTA function for my use with my ERB-EspWebServer Farm, but provided just some excerpts here for discussion. At some point I will post the complete listing on my GitHub.<br />
<br />
Sorry, I did not include the "set up", but I think the upper case "#define" are obvious. <br />
<br />
<pre><code>
// ###########################################################
//////////////////////////////////////////////////////////////
//
//
boolean
_MTA(WiFiClient client, String aStr, String aPat, unsigned long aTimeout)
{
boolean myStatus = false;
if (aStr.length() ) client.println(aStr);
yield();
// Wait For Response
unsigned long ts = millis();
while (true) {
if ( ts + aTimeout < millis() ) {
myStatus = false;
break;
}
yield();
#if (OPT_MONITOR_DEBUG_OUTPUT) > 0
DEBUG_INDENT; Serial.println(sE(" Waiting: ") + aPat + E(" . . . ") );
#endif
String line = client.readStringUntil('\n');
#if (OPT_MONITOR_DEBUG_OUTPUT) > 0
DEBUG_INDENT; Serial.println(sE(" ") + line);
#endif
if(line.indexOf(aPat) >= 0) {
myStatus = true;
break;
}
}
return myStatus;
}
// ###########################################################
//////////////////////////////////////////////////////////////
//
// Provides easy access to page via Email Gateway
//
boolean
eMTA( String aDomain = MY_DEFAULT_NODE_DOMAIN,
String aTo = MY_DEFAULT_EMAIL_TO,
String aFrom = MY_DEFAULT_EMAIL_FROM,
String aMesg = MY_DEFAULT_EMAIL_MESSAGE,
String aHost = MY_DEFAULT_EMAIL_HOST,
int aPort = MY_DEFAULT_EMAIL_PORT )
{
digitalWrite ( gBluLED, ON );
#if (OPT_MONITOR_DEBUG_OUTPUT) > 0
DEBUG_INC_INDENT; Serial.println ( E("Starting Email Client ...") );
#endif
boolean myStatus = false;
#if (OPT_MONITOR_DEBUG_OUTPUT) > 0
DEBUG_INDENT; Serial.println( sE(" Connecting to: ") + aHost );
#endif
// Use WiFiClient class to create TCP connections
WiFiClient client;
if (!client.connect(aHost.c_str(), aPort)) {
#if (OPT_MONITOR_DEBUG_OUTPUT) > 0
DEBUG_DEC_INDENT; Serial.println( E(" Connection Failed") );
#endif
myStatus = false;
}
else {
// Wait for Client to Start Sending
#if (OPT_MONITOR_DEBUG_OUTPUT) > 0
DEBUG_INDENT; Serial.println( E(" Waiting for Connection") );
#endif
// The MTA Exchange
while(true) {
if (_MTA(client, "", "220 ", 10*SECs ) == false) break;
if (_MTA(client, "EHLO " + aDomain, "250 ", 10*SECs ) == false) break;
if (_MTA(client, "MAIL FROM:" + aFrom + "", "250 ", 10*SECs ) == false) break;
if (_MTA(client, "RCPT TO:" + aTo + "", "250 ", 10*SECs ) == false) break;
if (_MTA(client, "DATA", "354 ", 10*SECs ) == false) break;
if (_MTA(client, aMesg + "\r\n.\r\n", "250 ", 10*SECs ) == false) break;
myStatus = true;
break;
}
client.flush();
client.stop();
#if (OPT_MONITOR_DEBUG_OUTPUT) > 0
if (myStatus == true) {
DEBUG_DEC_INDENT; Serial.println( E(" Connection Closed Successfully") );
}
else {
DEBUG_DEC_INDENT; Serial.println( E(" Connection Closed With Error") );
}
#endif
}
digitalWrite ( gBluLED, OFF );
return myStatus;
}
</code></pre>
<br />
As can be seen, the logic of the MTA is really very simple: send a message, and then wait for a response, repeat as necessary, stop on error or finished.<br />
<br />
Note: For the Raspberry IP, this can be implemented as a Bash script, in fact the details for the above program were first worked out using a script on a Linux Workstations. I will post the script later.<br />
<br />
If you find this useful - leave a comment.<br />
<br />
<br />
-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a><br />
<br />Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com9tag:blogger.com,1999:blog-7396057548824140336.post-90340471507016893222015-12-02T19:53:00.000-08:002015-12-14T12:25:48.510-08:00Playing with Diffie Hellman<b><a href="http://wa0uwh.blogspot.com/2015/12/playing-with-diffie-hellman.html">UPDATED:</a></b><br />
Added Details and Links<br />
<br />
Note: I am not a <a href="https://en.wikipedia.org/wiki/Cryptography">cryptographer</a>, I just like playing with large numbers.<br />
<br />
There are no secret information provided in this blog post, it is all available online, this is just my added two cents, take it for what it is worth.<br />
<br />
The <a href="https://en.wikipedia.org/wiki/Diffie%E2%80%93Hellman_key_exchange">Diffie-Hellman Key Exchange</a> method is used to share a "<b>Secret Key</b>" between two users, without sending the shared Secret Key across the network.<br />
<br />
See: <a href="https://en.wikipedia.org/wiki/Diffie%E2%80%93Hellman_key_exchange">Google Diffie Hellman</a>.<br />
<br />
The idea is simple, and the maths can be simple:<br />
<br />
<b>k</b>=<my secret number><br />
<b>g</b>=<a publicly shared number><br />
<b>p</b>=<a publicly shared large prime number><br />
<br />
A new Shared or Secret Key: <b>G = (g ^ k) mod p</b><br />
<br />
What can make it difficult and secure is that <b>VERY</b> large numbers can be used, and therefore making it very difficult for an observer (villain) to use brute force to discover the Shared Secret Key.<br />
<br />
If you read the available documentation about Diffie Hellman Key Exchange, you will no doubt learn all about; <b>Alice</b>, <b>Bob</b> (the good guys), and <b>Eve</b> (the villain). I suggest it for some bed time reading.<br />
<br />
Note: the online documentation suggest that Alice and Bob must first each know some public numbers for "<b>g</b>" and "<b>p</b>". <br />
<br />
But, there is nothing preventing a proper and secure Key Exchange when Alice initiates the process by sending Bob three numbers; "<b>g</b>", "<b>p</b>" and "<b>g2B</b>" (g to Bob) values.<br />
<br />
Bob would need to use these three values to compute the "<b>Shared Secret Key</b>". Bob also returns to Alice a computed "<b>g2A</b>" (g to Alice), now Bob is finished, he now knows the <b>Shared Secret Key</b>. Alice will also know the <b>Shared Secret Key</b> when she completes her next calculation.<br />
<br />
Alice uses the returned "<b>g2A</b>" value to compute the same "<b>Shared Secret Key</b>".<br />
<br />
It looks like magic, but it is simple when you look at the maths with small numbers, and knowing:<br />
<br />
<div style="text-align: center;">
<b>g^(ab) mod p == g^(ba) mod p</b></div>
<br />
where: "<b>a</b>" is Alice's secret key ("<b>kA</b>"), and "<b>b</b>" is Bob's secret key ("<b>kB</b>").<br />
<br />
See the online documentation. <br />
<br />
You will also learn from online documents, that "<b>p</b>" should be a Large Prime Number, and "<b>g</b>"
should be greater than "<b>0</b>", but less than "<b>p</b>", and "<b>k</b>" is a Secret Key
that should NOT be shared.<br />
<br />
Which is all good advice, if you are implementing a banking system, or saving the world via encrypted text messages. But the Diffie Hellman function works regardless of the numbers used, so in the examples below, some small and maybe inappropriate values are used.<br />
<br />
What started my interested in Diffie Hellman Key exchange is the UNIX provided, and neat little and powerful, utility called "<b>bc</b>". The "<b>bc</b>" command can deal with VERY large numbers without difficulty.<br />
<br />
<b>An Example:</b><br />
<br />
A Diffie Hallman Example, with small numbers.<br />
<br />
Assume that <b>Alice</b>, <b>Bob</b> and <b>Eve</b> will know and/or use the following:<br />
<br />
<b>gP =16</b><br />
<b>pP = 101</b><br />
<br />
As stated above, these numbers could be suggested by Alice or Bob, or both. Or, the numbers could be hard coded into a application that they both use. If large enough, the knowledge of these numbers does NOT detract from security.<br />
<br />
Note: For this example, I will use the upper case "<b>P</b>" to denote a number is "Public", "<b>pP</b>" is normally prime. I will use "<b>kA</b>" for Alice secret key, and "<b>kB</b>" for Bob's secret key. Also, "<b>g2B</b>" and "<b>g2A</b>" are the computed exchanged values. Then finally, "<b>gS</b>" becomes the value of the "<b>Shared Secret Key</b>".<br />
<br />
Note: "<b>g2B</b>" and "<b>g2A</b>" are just like other "<b>g</b>" values that can be used in the same Diffie Hellman formula.<br />
<br />
Eve can eavesdrop on all of the network data exchanges between Alice and Bob, but will NOT be able to compute the Shared Secret Key, because Eve is not privy to Alice's or Bob's Secret Keys.<br />
<br />
----------------------- <br />
<br />
Alice's Secret Key, known only by her, is:<b> kA = 7</b><br />
<br />
Alice wants to Share a Secret Key with Bob.<br />
<br />
Alice computes a: <b>g2B = (gP ^ kA) mod pP</b> with her key.<br />
<br />
Alice will do this on UNIX system with the values above using the following command:<br />
<br />
<div style="text-align: center;">
<b>$ g2B=`echo "(16^7)%101" | bc`</b></div>
<div style="text-align: center;">
g2B becomes <b>80</b> </div>
<br />
Alice can now send "<b>qP</b>", "<b>pP</b>" and "<b>g2B</b>" to Bob as clear text within an email (or whatever). Note: Eve may or can eavesdrop on the Internet traffic.<br />
<br />
----------------------- <br />
<br />
Bob's Secret Key, known only by him, is:<b> kB = 11</b><br />
<br />
Because Bob also uses a UNIX system, he computes from the values sent from Alice a value to be returned to Alice:<b> g2A = (gP ^ kB) mod pP</b><br />
<br />
<div style="text-align: center;">
<b>$ g2A=`echo "(16^11)%101" | bc`</b></div>
<div style="text-align: center;">
g2A becomes <b>71</b></div>
<br />
Bob can now sends Alice "<b>g2A</b>", so she can complete her side of the key exchange.<br />
<br />
<div style="text-align: left;">
Bob also can compute the "Shared Secret Key" as:<b> gS = (g2B ^ kB) mod pP</b> </div>
<br />
<div style="text-align: center;">
<b>$ gS=`echo "(80^11)%101" | bc</b>`</div>
<div style="text-align: center;">
gS becomes <b>54</b></div>
<br />
Bob is now finished, he knows the Shared Secret Key as "<b>54</b>". <br />
<br />
-----------------------<br />
<br />
With the value of "<b>g2A</b>" sent by Bob, Alice can complete her side of the exchange, by computing:<b> gS = (g2A ^ kA) mod pP</b><br />
<br />
<div style="text-align: center;">
<b>$ gS=`echo "(71^7)%101" | bc`</b></div>
<div style="text-align: center;">
gS becomes <b>54</b></div>
<br />
Alice now finished, she knows the Shared Secret Key as "<b>54</b>".<br />
<br />
-----------------------<br />
<br />
Both Alice and Bob both know the same value of "<b>gS</b>", the Share Secret Key as "<b>54</b>". Alice or Bob, could now use the <b>Shared Secret Key</b> to encrypt messages that <b>hopefully</b> only the opposite could decrypt.<br />
<br />
Eve is left clueless.<br />
<br />
-----------------------<br />
<br />
<b>But there is a flaw !</b><br />
<br />
With small numbers, as used in this example, Eve could Brute Force a decryption solution, by trying all numbers starting with "<b>0</b>". In this case it will only take <b>54</b> iterations to find the correct Shared Secret Key that would successfully decrypt Alice's message. Eve could easily know (via eavesdropping) the value of "<b>pP</b>" is small, and therefore, can assume the Secret Key is some number between <b>0</b> and <b>101</b>, which implies a brute force attack is warranted.<br />
<br />
<b>But Normally</b><br />
<br />
Normally, the values of "<b>gP</b>", "<b>pP</b>", and the resulting "<b>g2B</b>" and "<b>g2A</b>" are <b>VERY</b> much larger numbers, maybe hundreds or thousands of digits.<br />
<br />
Imagine what Eve prospects of having enough CPU horse power to attempt a sequential attack if "<b>pP</b>" is extremely large number - prospects = none.<br />
<br />
If "<b>pP</b>" is large enough, a brute force attack could take forever even with multiple very fast computers.<br />
<br />
<b>Some Experiments</b><br />
<br />
Remember I said "<b>bc</b>" can deal with large numbers, well, to avoid "typing" a large number I will use exponentiation to generate some numbers for "<b>qP</b>" and "<b>pP</b>", for Alice try this:<br />
<br />
<b>$ gP="(3^456)"</b><br />
<b>$ pP="(2^4253-1)" # A Large Prime Number</b><br />
<b>$ kA="12345"</b><br />
<b><br /></b>
<b>$ time echo "${gP}^${kA} % ${pP}" | bc</b><br />
<br />
On my 3.2GHz Workstation, this took about 6 minutes to compute, if necessary try shorten the lapse time, by changing Alice's key to "123". <br />
<br />
<pre><code>
$ gP="(3^456)"
$ pP="(2^4253-1)"
$ kA="12345"
$ time echo "${gP}^${kA} % ${pP}" | bc
80926261610442626577264521832490790161484618732554432140432039188058\
63206215275578738866144144831890725477013508191723348004478728927721\
95788786903156432412894232199564275068253627223471477034284902245829\
91421266442623706953457344345029183351048403313211524973218664085545\
87664348342026922029976056154815423683953094807171496683969416932115\
99132155230551185025739817346443301752666222054850477088018492513173\
91624760224393336362809726321106680382250456588357956381388166323729\
38771361918677860624224646340387910263769022858722611291936528412356\
03100668125135517222317410124988021081469568935461035793383680680665\
55390092789716566511778596204161424690071853937453863897083377508927\
67048039381017256779118656382146384480277810498377460548282809326731\
69234441684180112706844382298511472521071812891762065337050899792993\
70060526297317940169650082051030560624756658527561344770507458651702\
43716790444907248809569095106287466645236990947552803718232042574873\
11042448383261839081283910961519762548619655187688322601121778057413\
25524176872795543285574829694591574831681802471828336907766795593351\
38229222971475049624002124059810014875496597620324310354937668694220\
99070653730452586152318927155511512700751348007603716449001964877066\
01906432412801407287885578931224463376104843439581857726
real 5m48.432s
user 5m44.929s
sys 0m0.400s
</code></pre>
<br />
The results is about <b>1200 digits</b> for "<b>g2B</b>".<br />
<br />
<br />
Stay tuned, more interesting "<b>bc</b>" observations to follow.<br />
<br />
<br />
Me?, I just like very <b>BIG</b> numbers :-)<br />
<br />
-- Home Page: <a href="https://wa0uwh.blogspot.com/">https://WA0UWH.blogspot.com</a>Eldon R. Brown SRhttp://www.blogger.com/profile/16271671761017534867noreply@blogger.com0