Yesterday, Dave - W7AGJ came by my Shop. He had been to RPC (PC Recycling) in Seattle to buy a heat sink for a Home Brew Power Meter that he is building,
The large (about 6x5 inch) heat sink needed some of it's fins milled off of one side to provide a flat surface to mount to a the side of an enclosure he was planing to use. A lot of mill chips later, the heat sink was ready to mount. But, the aluminium enclosure was painted which prevents direct contact - after taping a mask (or shield) a paint patch, the size of the heat sink, was removed with the sand blaster.
Before leaving we discussed the frequency response of capacitors, Dave will need several for his voltage divider and detector circuit of the power meter. His goal is to provide reliable response from HF to 70cm (450mHz).
Using my AIM-4170B it was easy to see the effects of lead length and the different types of capacitors - it was not looking good for my best and available junk box capacitors above 150mHz. Dave is hoping to select the diode, capacitor type, lead length and construction methods to minimise the need for radical calibration chart - we will see. One idea, is to use several; Parallel, Surface Mount or Mica Capacitors.
Dave will no doubt want to scan his new project with an analyser with a greater frequency range than that which is possible with an AIM-4170B (1-181mHz).
I will continue to follow this project.
NOTE: RPC as mentioned above is a great place to find parts for Home Brew QRP project, re-purposed PC boards/equipment/parts are abundant for only very few dollars.
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Showing posts with label W7AGJ. Show all posts
Showing posts with label W7AGJ. Show all posts
Monday, December 28, 2009
Sunday, December 20, 2009
December 2009 - eBuild-A-Thon and BBQ
The December 2009 eBilld-A-Thon and BBQ has come and gone, a great day of working and chating with fellow HAMs about electronic projects.
Two new visitors from the SkyValley Ham Club came by to see the Shop:
Dave - W7AGJ from SkyValley came by, he wanted more information on my Cordless Soldering Iron - he was looking for proper specification for describing it to Santa.
The Beacon Hunt
The hidden QRSS "Beac-in" was located by Jeff - KO7M within about 15 minutes of his arrival, using a portable Elecraft KX1 Transceiver with a clip lead from the antenna jack to his umbrella frame (it was raining). Jeff used low RF gain on the Transceiver and signal strength to Home in on the Beacon. Later, Jeff admitted that physcology was also used, as he looked in places that he thought I would have used for the hiding place. For the next hunt, I will try to make the hunt and physcology much harder.
For being the first to find the Beacon, Jeff will receive the prize - A pick of one of my QRSS/WSPR marker beacons, or a custom copy that we build during the event. He chose a custom copy - more on that later.
The Projects
Roger - K7RXV brought a very special KIT for all to enjoy, his kit was the fixings for Russian Mushroom and Potato Soup. He started just after arrival, he was busy chopping, cutting and saute'ing bits-n-pieces for what seemed like several hours, it was ready on-time for lunch. It was excellent, I highly recommend it! I plan to save the above link to the recipe for another time. Good job Roger!
Jeff - KO7M brought his Elecraft KX1 Transceiver, we enjoyed listing to CW QSO's and his operations. We had to ask him to connect it up to some speakers for all to hear.
John - KC7NVE brought one of his KITs, A Scout Regen Receiver (I think) to start the build process, on arrival John had a sack of parts and boards. When he left, his parts were all labeled, organised and sequenced for easy access for the later build process. Not only is John a great HAM, he is an amazing organiser.
Doug - W7RDP brought the chassis of a KIT he was starting, it needed holes drilled, punched, and the heat sink tapped. Doug spent most of his time at the Drill-Mill and helping with other projects.
Lunch
Thanks to: Carolyn (my sister) for helping with cookies and Tacos; and Roger for the Potato Soup. We had enough food for an army - I was stuffed.
The Beacon Hunt Prize
For Jeff's Beacon Hunt prize, we went through the complete project, from a custom modified PCB layout on the computer screen, to a finished working Marker Beacon. We changed the layout to include his CALL on the artwork for the PCB. We used the Toner-Transfer Method to build the PCB. I installed the first part, Jeff installed all of the rest, using the schematic and a previous working beacon as a guide.
On the first turn-on, only a chirp was heard on the receiver when the key was pressed. We inadvertently used an old junk battery that was sitting on the bench that was almost dead. The circuit board was double-sided taped to the battery and had to be removed. With a new battery, we tried it again - this time nothing! It did not make a sound at the receiver.
It is now trouble shooting time! Jeff compared the voltages between the working Beacon and his new Beacon, all voltages were the same. Because we used a new untried crystal in this Beacon, it was suspect - maybe it just would not oscillate. Remember this circuit is made of all surface mount components, and therefore it is somewhat difficult to check individual components. When a circuit has never worked before, it is sometimes difficult to know where to start troubleshooting.
We decided to remove the crystal and replace it with another. While cleaning the pads with solder wick to receive the second crystal, the series capacitor moved. That is, one half of the capacitor fell off, with the other end still soldered to the board. This was surely the problem - a cracked capacitor. We may have cracked the capacitor while prying the circuit off of the the old battery.
We replaced the capacitor, and did a trial press fit of the crystal in place - it worked! About this time, my Soldering Iron was low on battery charge, and therefore we had to wait for it to charge, to see the real results (don't ya just hate that?)
In the end, after the crystal was properly installed, a quick twist of the tuning trimmer put the Marker on frequency (10.140100mHz) . The Project was a success!
Other Topics
Sometime during the day we discussed a QRSS Beacon balloon launch (see previous post), many aspect of a balloon project are still up-in-the-air (no pun intended). To be successful, we will need to enlist as many US Grabber as available. From our Seattle area, the upper wind is just right for a long flight across the US.
Jeff also brought in his fantastic Valve (Tube) Regen Receiver. There has been a lot of talk about valve receivers on the WEB recently and I had forgot how enjoyable it is to look at the glow of a valve while in operation. From that dull red glow comes the magic that got me into HAM Radio in the first place, many years ago. It was good to hear and see Jeff's receiver.
(I think John may have a better photo, I'll see if I can get a replacement)
Update: Thanks to John the following four photos are added.
Conclusion
Because the winter evening come early in Seattle, the group left about 5pm - I enjoyed the day of having the guys at the Shop.
Tess enjoyed the attention and playing ball with all of the guys, she was dead tired by the end of the day. After going bed, I don't think she moved all night.
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Two new visitors from the SkyValley Ham Club came by to see the Shop:
- Dave Zehrung - AA7L and his young grandson (I think) Brandon Williams - KF7EZE
Dave - W7AGJ from SkyValley came by, he wanted more information on my Cordless Soldering Iron - he was looking for proper specification for describing it to Santa.
The Beacon Hunt
The hidden QRSS "Beac-in" was located by Jeff - KO7M within about 15 minutes of his arrival, using a portable Elecraft KX1 Transceiver with a clip lead from the antenna jack to his umbrella frame (it was raining). Jeff used low RF gain on the Transceiver and signal strength to Home in on the Beacon. Later, Jeff admitted that physcology was also used, as he looked in places that he thought I would have used for the hiding place. For the next hunt, I will try to make the hunt and physcology much harder.
For being the first to find the Beacon, Jeff will receive the prize - A pick of one of my QRSS/WSPR marker beacons, or a custom copy that we build during the event. He chose a custom copy - more on that later.
The Projects
Roger - K7RXV brought a very special KIT for all to enjoy, his kit was the fixings for Russian Mushroom and Potato Soup. He started just after arrival, he was busy chopping, cutting and saute'ing bits-n-pieces for what seemed like several hours, it was ready on-time for lunch. It was excellent, I highly recommend it! I plan to save the above link to the recipe for another time. Good job Roger!
Roger - Working at his Cook KIT
Jeff - KO7M brought his Elecraft KX1 Transceiver, we enjoyed listing to CW QSO's and his operations. We had to ask him to connect it up to some speakers for all to hear.
Jeff - Transceiver Operation
John - KC7NVE brought one of his KITs, A Scout Regen Receiver (I think) to start the build process, on arrival John had a sack of parts and boards. When he left, his parts were all labeled, organised and sequenced for easy access for the later build process. Not only is John a great HAM, he is an amazing organiser.
John - Labeling Parts for his KIT
Doug - W7RDP brought the chassis of a KIT he was starting, it needed holes drilled, punched, and the heat sink tapped. Doug spent most of his time at the Drill-Mill and helping with other projects.
Doug - Supporting Jeff's Marker Build Project
At the Mill/Drill
More Hardware Discussions in the Shop
Jeff - Hard at Work on a small SMD
Lunch
Thanks to: Carolyn (my sister) for helping with cookies and Tacos; and Roger for the Potato Soup. We had enough food for an army - I was stuffed.
Lunch Break
The Beacon Hunt Prize
For Jeff's Beacon Hunt prize, we went through the complete project, from a custom modified PCB layout on the computer screen, to a finished working Marker Beacon. We changed the layout to include his CALL on the artwork for the PCB. We used the Toner-Transfer Method to build the PCB. I installed the first part, Jeff installed all of the rest, using the schematic and a previous working beacon as a guide.
Marker, Still Under Construction
Jeff - Hard at Work under to Magnifier
On the first turn-on, only a chirp was heard on the receiver when the key was pressed. We inadvertently used an old junk battery that was sitting on the bench that was almost dead. The circuit board was double-sided taped to the battery and had to be removed. With a new battery, we tried it again - this time nothing! It did not make a sound at the receiver.
It is now trouble shooting time! Jeff compared the voltages between the working Beacon and his new Beacon, all voltages were the same. Because we used a new untried crystal in this Beacon, it was suspect - maybe it just would not oscillate. Remember this circuit is made of all surface mount components, and therefore it is somewhat difficult to check individual components. When a circuit has never worked before, it is sometimes difficult to know where to start troubleshooting.
We decided to remove the crystal and replace it with another. While cleaning the pads with solder wick to receive the second crystal, the series capacitor moved. That is, one half of the capacitor fell off, with the other end still soldered to the board. This was surely the problem - a cracked capacitor. We may have cracked the capacitor while prying the circuit off of the the old battery.
We replaced the capacitor, and did a trial press fit of the crystal in place - it worked! About this time, my Soldering Iron was low on battery charge, and therefore we had to wait for it to charge, to see the real results (don't ya just hate that?)
In the end, after the crystal was properly installed, a quick twist of the tuning trimmer put the Marker on frequency (10.140100mHz) . The Project was a success!
Other Topics
Sometime during the day we discussed a QRSS Beacon balloon launch (see previous post), many aspect of a balloon project are still up-in-the-air (no pun intended). To be successful, we will need to enlist as many US Grabber as available. From our Seattle area, the upper wind is just right for a long flight across the US.
Jeff also brought in his fantastic Valve (Tube) Regen Receiver. There has been a lot of talk about valve receivers on the WEB recently and I had forgot how enjoyable it is to look at the glow of a valve while in operation. From that dull red glow comes the magic that got me into HAM Radio in the first place, many years ago. It was good to hear and see Jeff's receiver.
The Dull Red Magic Glow of from Valve Receiver,
Unlike smoke, the Glow is something that you DO enjoy letting out of a Component.
(I think John may have a better photo, I'll see if I can get a replacement)
Update: Thanks to John the following four photos are added.
Now, . . . This is What The Magic Is All About!!
ReGen Receiver In Operation
Jeff - Working with his Regen Receiver
Conclusion
Because the winter evening come early in Seattle, the group left about 5pm - I enjoyed the day of having the guys at the Shop.
Tess enjoyed the attention and playing ball with all of the guys, she was dead tired by the end of the day. After going bed, I don't think she moved all night.
-
Tuesday, October 27, 2009
The Marker Family Photo
Dave Axe - W7AGJ came by my Shop today while I was working on board design for the replacement QRSS Receiver, previously I was working on the last Band Edge Marker Oscillator and had just gather them into a group on the bench. Something was said about they looked like they were there for a Family Photo - So, why not - here it is!
The pre First - Not shown in photo, was an "Ugly Style Leaded" oscillator soldered to the top of a 9volt battery clip, photo is available in another Album.
Here is the Family, from left to right:
I do not currently have plans to expand the Family - Or, at least not until I can mount all of the components on the side of the Crystal, my skill level will need some improvement first.
This was a fun project - Now onto,Bigger Smaller and Better Things
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The pre First - Not shown in photo, was an "Ugly Style Leaded" oscillator soldered to the top of a 9volt battery clip, photo is available in another Album.
Here is the Family, from left to right:
- The First, was created to try to use SMD parts in Ugly Style.
- The Second was the previous circuit in SMD Flat Layout, not all parts are SMD, I had just started using PCB Layout Tools and found PCB-FAB-In-A-Box.
- The Third - using all SMD parts (except Crystal, Switch, and Antenna).
- The Forth - New Layout and added a previous forgotten part - a decoupling cap, which made for low output.
- The Fifth - New Layout, while trying to make it as small as possible.
I do not currently have plans to expand the Family - Or, at least not until I can mount all of the components on the side of the Crystal, my skill level will need some improvement first.
This was a fun project - Now onto,
Don't you just love this Radio/Electronic Stuff!
If NOT, you should not be reading this Blog
Saturday, October 17, 2009
October 2009 - eBuild-A-Thon and BBQ
We just finished the third - eBuild-A-Thon and BBQ.
I neglected to get a proper list of attendee, so, sorry if the following details are incorrect.
Due to previous commitment, some of the Sky Valley Amateur Radio Club Hams came by early and were unable to stay the whole day. We toured the Shop and discussed future suggested projects, including proposed PCB design methods.
Sky Valley Attendees were:
As usual, Tess - my dog, was uneasy with all of the visitors, she loves kids and warms up to them quickly, but adults are different. Knowing that Tess loves to chase Balls, I decided to try something different with this group and Tess. Carolyn (my sister) helped to find Tess a ball, that could be thrown or kicked by each person - after that, each person was Tess's friend and all apprehension was gone. Only with a loud clap of thunder, from the approaching storm, did the ball play stopped for shelter at my feet.
John - KC7NVE, brought his Transceiver, Laptop and did some PSK31 set up and work. He used my 30m vertical antenna and was able to use the built-in antenna tuner to match it for other bands.
Roger - K7RXV, brought his newly minted Two Port Network Analyser (from http://sdr-kits.net/) , to try out and show the group it's operation. After a technical discussion of it's attributes, we connected it to my 30m antenna to review it's tuned configuration. The Network Analyser reported a 1.05:1 SWR at a frequency slightly above my normal use at 10.140mHz - I was thrilled!
While testing the 30m Antenna, and during a fast moving rain squall, the Analyser report went nuts, SWR went way up and the resonate point flattened and lost definition.
Question: with all of the playing with the Antenna Analyser, did we change something that messed up the report?
No, with a lot of investigation, we found that the feed-point-ground at the base of the antenna was intermittent. The ground point was implemented via a spring clipped copper strap around the ground support. The previous days of windy-stormy weather must have loosened the clip and made it intermittent during the current rain squall and for our tests. A quick snap of a pair of vice-grip pliers, solved the problem (I'll fix a permanent solution later).
Three of the Donkeys came to the Shop edge, and tried to provide insight into our antenna problem, but by that time we had the problem solved. Therefore, they only received sugar cubes for their efforts.
Jeff - K07M, brought in several of his projects that he has been using with his airplane for reporting his position, via the web, while traveling across country. He has several ideas for mounting the newer generation of hardware within his plane. I have seen several of Jeff's kit built projects - Jeff is a Master Builder, with excellent soldering techniques.
When Dave - W7AGJ, returned, he provided a prepared report on the propagation terrain path from the Sky Valley 2m Repeater to my QTH. It is no wonder that I have trouble receiving the repeater. In the three miles path there are several ridges, with trees, higher than line of sight between the repeater and my QTH. The suggested solution; was a Chain Saw, or a higher fixed base station antenna. Unfortunately, the antenna will have to wait.
I re-demo'd the "PCB Fab-In-a-Box" building techniques, we created another small PCB, which we also used it to practice SMD soldering techniques.
There were many other discussions and activities that have not be mentioned - but for more on that, you will just have to join us and enjoy!
-
A Note:
It is great to be associated with such great Amateur Radio artistic Knack giants, where harmonious discussions provides each with something more than the sum of the parts.
After twenty plus years of teaching short technical courses, I have developed and validated a Theory:
E-Mail:
-
I neglected to get a proper list of attendee, so, sorry if the following details are incorrect.
Due to previous commitment, some of the Sky Valley Amateur Radio Club Hams came by early and were unable to stay the whole day. We toured the Shop and discussed future suggested projects, including proposed PCB design methods.
Sky Valley Attendees were:
- Tom Singleton - K8TOM and his Sons (didn't get their calls)
- Charlie - N6IBI
- Diane - KE6JRP
- Dave Axe - W7AGJ
- Roger - K7RXV
- John - KC7NVE
- Jeff - K07M
- Dave Axe - W7AGJ - Returned for the second visit
As usual, Tess - my dog, was uneasy with all of the visitors, she loves kids and warms up to them quickly, but adults are different. Knowing that Tess loves to chase Balls, I decided to try something different with this group and Tess. Carolyn (my sister) helped to find Tess a ball, that could be thrown or kicked by each person - after that, each person was Tess's friend and all apprehension was gone. Only with a loud clap of thunder, from the approaching storm, did the ball play stopped for shelter at my feet.
Tess inspecting the base of the Antenna, . . . .
Or is that the Ball that she wants!
Or is that the Ball that she wants!
John - KC7NVE, brought his Transceiver, Laptop and did some PSK31 set up and work. He used my 30m vertical antenna and was able to use the built-in antenna tuner to match it for other bands.
Roger - K7RXV, brought his newly minted Two Port Network Analyser (from http://sdr-kits.net/) , to try out and show the group it's operation. After a technical discussion of it's attributes, we connected it to my 30m antenna to review it's tuned configuration. The Network Analyser reported a 1.05:1 SWR at a frequency slightly above my normal use at 10.140mHz - I was thrilled!
Reviewing Analyser Reports
While testing the 30m Antenna, and during a fast moving rain squall, the Analyser report went nuts, SWR went way up and the resonate point flattened and lost definition.
Question: with all of the playing with the Antenna Analyser, did we change something that messed up the report?
No, with a lot of investigation, we found that the feed-point-ground at the base of the antenna was intermittent. The ground point was implemented via a spring clipped copper strap around the ground support. The previous days of windy-stormy weather must have loosened the clip and made it intermittent during the current rain squall and for our tests. A quick snap of a pair of vice-grip pliers, solved the problem (I'll fix a permanent solution later).
This is a temporary Ground connection Fix
Three of the Donkeys came to the Shop edge, and tried to provide insight into our antenna problem, but by that time we had the problem solved. Therefore, they only received sugar cubes for their efforts.
The Rejected Antenna Engineering Support Crew
Jeff - K07M, brought in several of his projects that he has been using with his airplane for reporting his position, via the web, while traveling across country. He has several ideas for mounting the newer generation of hardware within his plane. I have seen several of Jeff's kit built projects - Jeff is a Master Builder, with excellent soldering techniques.
When Dave - W7AGJ, returned, he provided a prepared report on the propagation terrain path from the Sky Valley 2m Repeater to my QTH. It is no wonder that I have trouble receiving the repeater. In the three miles path there are several ridges, with trees, higher than line of sight between the repeater and my QTH. The suggested solution; was a Chain Saw, or a higher fixed base station antenna. Unfortunately, the antenna will have to wait.
I re-demo'd the "PCB Fab-In-a-Box" building techniques, we created another small PCB, which we also used it to practice SMD soldering techniques.
There were many other discussions and activities that have not be mentioned - but for more on that, you will just have to join us and enjoy!
-
A Note:
It is great to be associated with such great Amateur Radio artistic Knack giants, where harmonious discussions provides each with something more than the sum of the parts.
After twenty plus years of teaching short technical courses, I have developed and validated a Theory:
The Instructor always learns more from a teaching event, than the Student.
And now, after Hosting three eBuild-A-Thon events in my Shop, I have developed the first Corollary:
The Host always enjoys more from a technical event, than the Attendee.
My validation is as follows; there is no way that a person has the capacity to contain or could obtain more enjoyment than I, from hosting these events! . . . . .
Thanks to my Friends - Eldon - WA0UWH
E-Mail:
Eldon,
I wanted to just say a big "thank you'" to you and your sister Carolyn for hosting us on Saturday. I know that there are others from the club that were very interested in visiting your place, but couldn't make it this time. Based on word of mouth reputation and a little more lead time on the announcement, I wouldn't be surprised to see several more folks there next time.
Anyway, it is extremely kind and generous of you to allow us there as guests and hobbyists. It's just a fabulous place. I will try to remember to send out the meeting notice a bit earlier this time to hopefully allow folks to be able to reserve some time to come by.
This is the sort of fellowship and help that radio clubs are established to foster, and I am very appreciative of your contribution.
73,
Tom
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