Tuesday, April 19, 2011

A Forgotten Useful Tool

I have recently been made aware of a great Smith Chart Program and Tutorials, thanks to Dennis Eckert - KB7ST and his post on the pQRP list reflector.

I have used a hand Smith Chart many years ago, and since forgot most of what I knew.

See:
Program by 

The six tutorials are a good overview of the program, and a very good refresher of why I should be using it more often with my Homebrew projects. The Smith Chart Program is now going to be a constant companion, on the bench, for use in all projects.

Click the tutorials, see if you do not agree. Be sure to read the Primmer and the QRP Quarterly (pdf).

The Yahoo Group SimSmith Forum is at:

Thanks - Dennis for the pointer, and Thanks, Ward, for the Program and your Efforts!

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Monday, April 18, 2011

Boards Received from China

I am an avid Homebrew PCB builder using the Toner Transfer Method, I can build a single sided board (similar as shown below) in about 20 minutes, and a double sided board in about one hour. I can also apply a green UV Curable Epoxy Solder Mask on either or both sides. A solder mask takes about 2 hours to apply.

As an experiment, I wanted to try the services of a commercial PCB production shop, the following is the initial results.

My 30m Beacon circuit boards was sent out for processing, it just arrived back from the PCB manufacture in China.

发件人: IteadStudio
发送时间: 2011-04-15 23:44:47
收件人: order
抄送:
主题: Fw: Re: Order Update #1550
After receipt and close inspection, I am very pleased with the results.

The schematic and board was designed with DipTrace Software and then six Exported Gerber Files and one Drill file were sent via e-mail to IteadStudio.com in China for manufacture.

To access the PCB service at IteadStudio.com; click on the tab on the site's top; "iStore -> OpenPCB -> PCB Prototyping Service".

The Original Layout as Designed in DipTrace PCB Software

As shown via the DipTrace 3D Preview Software

This is a photo of the resulting PCB as Received from Iteadstudio.com

The results are amazing. This is a; 1x2 inch board, with 8 and 6 mil Traces, 10 mil Clearance, the Ground Grid is 8 mils on 24 mil centers, and the Plated-through VIA's are 40 mils with 15 mil holes.

As shown in the magnified view below, there are multiple ground grid traces between the 1/10 inch on center Header holes. The square SMD pads are for 0603 LEDs and their 0603 limit resistors.

       
As Designed                                                    As Shipped

I received 10 boards for $12.00 plus $4.00 Shipping, that is $1.60 per board - a very good value. To obtain this low price, boards must be equal or less than 5x5 cm. Larger boards are available, but at higher price.

The only down side is the shipping time from China, it was 15 days after manufacture, 22 days total. But the results for this hobbyist was well worth it!

 Five of the 10 Boards are Marked as  being Tested

Chris and Dave of the TheAmpHour.com put me onto this great available service - Thanks Guys.

Note: I did not experience the Ground Plane Dropout as Dave Blogged, but then maybe I did not use similar geometry.

I am very pleased with the quality and results, and plan to use the service again, where multiple copies are needed and turn-around delay is acceptable. But, for my "one off" projects, I will continue to use the Homebrew Toner Transfer Method.

OK, one nagging question, what am I going to do with ten of these circuits, when I really only needed one or two? Well, this was just a test or exercise of the process, for later and more sophisticated circuits, and where copies will be sold.

Soon, I will post the results after loading a board.


UPDATE
I found a similar priced and faster service, based in Portland, OR. See: my follow-on post.


-- Home Page: https://WA0UWH.blogspot.com

Sunday, April 17, 2011

A full Amateur Radio Day

My Saturday was a very full day of Amateur Radio, it started early at about 5:30AM, with it being wet, rainy, foggy and cold, it was not exactly a very good day for what was planed

The first thing on the schedule was attending the monthly Sky Vally Ham Radio Club Breakfast. In the past the breakfast meeting were held only about 3 minutes from my home, but with the old restaurant closing and my recent move, the travel time is now a little over an hour to the new location at the Mountain View Diner in Gold Bar, WA. The formal meeting starts a 8AM, but I try to get there about an hour before, as several members show up early just to chat.

Later, my friend Jeff - KO7M and I planned to take down a 40 foot tower with a vertical on top.

The drive from the restaurant to the the tower site was yet another hour. We planned to be on site about 11:00AM and planned to be finished around 3pm. The weather cleared and was only threatening rain.

Jeff was prepared with the required climbing and safety gear, and the Gin Pole was at the ready.

The home owner and I were the ground crew, attending ropes and providing verbal support.

The top section and the vertical were to be taken down together, thinking that the antenna would weigh much less than the top section of the tower. Wrong!  They were about the same weight or at least the center of gravity of each was about same distance from the rope tie point. It was a good thing we had a handling rope attached to the bottom of the top tower section. The two wanted to quickly rotate to the horizontal, but we were prepared. The antenna and top tower section were lowered together without further difficulty.

The three lower tower sections were taken down, uneventful,  as planned.

Due to one thing and then another, we did not finish until 6:30pm, and then there was yet another 1.5 hour drive back to home. By the time I got home it was late and I was exhausted (I hate getting old) - but it was a very good day of Amateur Radio.

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Sunday, April 10, 2011

BlogBooker

For several years I have been wanting to print a copy of my complete blog with photos, in the natural chronological order (oldest post first).

When first investigating the possibility, it seemed difficult and/or expensive. Some available services will format and print a hard cover book if requested (eg, Blog2Print). Maybe someday I will use their services.

But, for now, I just need a simple hard copy.

Today I found "BlogBooker", which does the task online for Free (the service is supported by user donations). The results are good, even though some useful text formating was lost. For example, some blanks lines between paragraphs were lost. But, the results are very acceptable for my current use.

The output is a saved PDF.

This info is archived here for later use.



UPDATE
It appears Blog2Print can be used to print anyone's blog, while BlogBooker can only be used by the author.

Blog2Print only requires the Blog URL, and some optional formatting, binding, and time span parameters, to produce the output. Hardbound books are available, and for a much lesser price soft copy PDF are available.

BlogBooker requires access to an exported XML file of the Blog. I assuming only the author of the Blog has access to the required exported file.

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Saturday, April 9, 2011

Another Hamfest, in Yakima

Today Tess (my dog) and I got up at 5:00AM to drive 150 miles to Yakima Washington for the W7AQ Hamfest.

After spending a lot of time in my shop, I need a change of scenery and the drive would be fun (maybe). The local weather was threatening rain, which may mean snow on I-90 Snoqualmie Pass (at about 3K feet). I planned to drive as far as possible (with my light van) without tempting destruction on slippery roads. Off we went, with foul weather gear, Cell Phone and the FT-817.

The big shock was at the Fuel Pump - $3.96 per gallon.

My Droid Cell Phone was set to simultaneously run; the GPS Navigator Program, Monitor the On Board Diagnostic (OBD) via bluetooth, and run the APRS reporting program.

Interesting; the Navigator Program reported that we were going to "Yeah Kee' Ma", which was good for a chuckle. It is obvious the "text to speech" program is not familiar with the Pacific Northwest Indian names.

It will be fun to see the OBD engine information showing; engine load, fuel usage, input air temperature, and air mass, while driving over the passes.

As it turns out, all of the roads were clear and dry, traffic was rolling along about 75 mph over the I-90 pass. The snow was stacked about 12 feet on the sides of the road near the Ski Lodge at the summit.

The one-way trip, with a few stops, took about 3.5 hours, arriving 45 minutes after the doors opened. I understand from a few attending friends that the "good stuff" was sold within the first 20 minutes - Oh well, I was there for the trip.

The place was crowed, with lots of conversation and hot deals. It seems the major volume of the crowd arrived about 10:00AM.

As usual, I found the Air Variable Caps for sale, with some good prices, but again, I resisted temptation for the need for more. From previous posts, you might know, I have a fetish for Air Variable Caps.


There were several interesting Fixed Air Caps, the like I have never seen before, very large with plate gaps of about 1/4 inch (see center right of photo). They look like Variables, but the are Fixed. I would loved to have them, but I do not know where I would ever use them.

For a treasure, I purchased some small 5K POTs (with switches) for use in my small projects, 20 for a buck. I am not sure of the taper, but should be good for tuning via varistor or a simple volume control.

On the way home I decide to go north toward Wenatchee and the tourist destination town of Leavenworth (the GPS Navigator also had fun with those two names) and then crossing the Cascades at Stevens Pass (US Route 2) . This route is less traveled in the winter because it is mostly a two lane road, and at much higher elevation (4K feet), but it is normally plowed and well traveled by the skiing crowd. At the top of Stevens Pass, the Snow was stacked about 25 feet, the road was clear and dry.

Note: While researching the included links in this post, I learned something new, "US Route 2" should have been named "US Route 0", assuming the naming convention was strictly upheld. The Highway Department did not want a "0" name route, and therefore picked the next even number for this road. It is also the only US Named Route that was planned, from the beginning, to contain two disconnected segments. Guess where the missing segment can (not) be found.

At home, while reviewing the APRS data it appears that my Cell Phone APRS reporting program was not always running on the return trip, or it had trouble accessing reporting stations. Maybe I forgot to restart it after a fuel stop, and/or I know the cell data connection was lost in the tight turns of the narrow river canyon.

Along the way, I listen to 2m and scanned the bands. I still do not have the FT-817 programed well enough for interactive use while driving.

It was a great trip, and it only cost me; $8.00 for admission, $1.00 for POTs, plus some for Fuel and Food (which works out to be about $6.00 per purchased part!).


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Sunday, April 3, 2011

HB PCB 3D Models

With time and work, I have created a few missing 3D components (see previous post) for my current project as shown via DipTrace (Beta) 3D PCB Layout program. The difficult task was finding a 3D modeling program that was easy to use and that can write the correct file format that DipTrace uses for it 3D Display.

I have now created the missing; Headers, Binocular Core, Trimmer Caps, and Trimmer Resistors 3D models to complete my current PCB project.

I used the AC3D Modeling Program to create the components. Unfortunately, AC3D can not read the resulting saved files. AC3D can Export VRML-2 file formats (which I need for the DipTrace PCB program), but it can not read the resulting VRML-2 file.

It would be nice if AC3D could also Import VRML-2, so that the Standard DipTrace 3D components could be used as reference or updated. Currently, I have been also saving all of my new components in the native AC3D format for later updates.

I have used AC3D for many previous mechanical projects, but to be more productive here, I need to continue to my search for a easy to use 3D Modeling program, that can natively Read and Write VRML-2 file formats.

It is interesting how productive the new DipTrace 3D View has become. Because of the 3D view, I have been able to modified the layout, by moving components closer and therefore saving space.

Waiting the 6-10 days for my PCB to return from the Chinese Manufacture has been a little frustrating, compared to building my own HB PCB. But, building the 3D components to complete my 3D model has been enjoyable.



UPDATE:
I just received e-mail notice that my Chinese Manufactured PCBs are complete, and now in the mail, Woohoo!

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Friday, April 1, 2011

DipTrace Beta

Several of the available PCB layout tools provide 3D Previewing as a standard function. The PCB software that I follow are:
From my perspective, each have their advantages and aggravations.

AuoTRAX has some really interesting features that I would like to use, but alas, AutoTRAX does not currently run on Linux or Ubuntu with Wine, which is my OS of choice and available in my shop and office (I am hopeful).

Most of my aggravations with DipTrace have be noted within my previous blogs and/or sent to DipTrace Developers where they were added to a long list of user requested enhancements.

Even with DipTrace's aggravations, I keep returning to DipTrace because of it's unique crosshatch copper pour ability, and because the support group has recently created some very instructive verbal video tutorials.

Crosshatch copper pour are well suited to the Toner Transfer Method of creating PCB's, as large blocks of Black Toner do not print, transfer or etch very well.

The New Beta Release of DipTrace (Mar 2011) now has a 3D Previewer feature.

In the past, I could only publish the PCB layout art for my projects.

With this new 3D function, I can now publish or document 3D views of the proposed results.

For Diptrace, 3D is still in Beta, and therefore some of the expected tools are not well developed. For example; an easy to use "Model Browser" for the library of 3D models does not exist. Currently all of the 2580 models are jammed into a single directory, where finding a particular model is problematic, especially if it's name is unknown. Even if you know the part family, it is a long iterative process to find the exact model that you are looking for. I know this is Beta, but the current aggravating usage part of this is;  the model viewer/selector process continually "opens" and then "closes" the model directory when used,  and each time it re-lists all of the 2580 models from the beginning.

Also, some simple standard models are not available, for example I could not find simple 3-pin fan headers, or anything like it. Note: the lack of headers, switches, coils, toroids, and trimmers in the above 3D view.

Hopefully more models and a better model Browser tools is being planned.

To make my use of the 3D Model Library easier, I spent about 4 hours sorting and dividing the 2580 Beta models into Family Directories. Now once within a Family Directory with only a few models, exploring different styles or revision of a part is much easier. A Viewer or Browser "Back/Next" button on the current viewer would be very useful, because the current method of opening the directory and scanning to a model file is very laborious.

Unfortunately, the supplied DipTrace 3D Library Model Viewer is like most MS products that are stuck with the authors vision of what display size should be used. The window is not scalable to take advantage of a large screen. Therefore, a large display user, must unnecessarily look at small window.

I am hopeful that the current DipTrace Beta with the new 3D Preview function is just the beginning of good things to come.

Note: I have recently sent the above board out to a Chinese PCB Fabrication Shop, this is a first for me. It will be interesting to see the results.

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Tuesday, March 29, 2011

I Need More Magic

I have been building HomeBrew PCBs via the Toner Transfer Method for a long time, as seen in previous posts. I am still trying to perfect my use of this method, where I can expect the same results each time.

There is sill some Magic to be learned.

Currently I am trying to perfect the alignment of the second side of a two sided HB PCB. I am trying circle Targets as common art for alignment guides. So far, I have had limited, and unpredictable success.

The lack of success is not that I can not align the circuit pads for each side, but how to repeatedly do it.

The current difficulty is; My Targets keep falling off of the PCB in the water soak bath, before they can be used.

In an attempt to do everything just right, I created another revision of my QRP QRSS Beacon, which is a two sided board of about 2 inches by 1 inch. The Targets that I am using are about 1/2 inch diameter placed around the edge of the board at random locations.

For this run, I was careful to clean the board as usual, and run it through the laminator several time as before (about 5). Normally, I run PCB and Transfer Paper sandwich inside of a small pocket made from a manilla folder. Successive passes are with the sandwich just setting on top of the folder pocket material, so that the Transfer Paper is in closer contact with the heated roller and the overall thickness is the same.

I have always had a problem getting good transfer results near the edge of the PCB material, and therefore have always provided a boarder of about 1/2 inch around the desired circuit art work. Now with my Targets in that boarder area, they are the art that is being lost.

I tried to get everything just right for this run. All was going well, until I was walking to the sink where warm water was waiting to dissolve the transfer paper release agent.

As I walked, I heard a "snap", from the PCB and Transfer Paper sandwich which I held in my hand. I could see the sandwich starting to separate at the edge. The "snap" that I heard was the targets releasing from the PCB material.

I think cooling and/or shrinkage of the PCB or Transfer Paper is the problem. From previous experiments, I was concerned that this might happen, so I let the sandwich cool naturally after the laminator. But, apperntly it cooled further as I walked to the sink.

As can be seen in the photo, the circuit art in the center of the board transfered perfectly, even with it's small 8/8 circuit traces. Only some of the Targets were lost, but this attempt was all about obtaining good targets.

Three Targets across the top, and portions of the lower targets were lost in the water bath, ghostly outline remains on the copper from where the Targets were previously attached.

I know from previous non-PCB experiments, moisture content has an effect on paper that is put through a laminator. Here in the Puget Sound area humidity levels are high and may be problem that needs to be understood and taken into consideration.

Now, what to do about this heating and shrinking problem, or how to avoid the bad results?

Maybe preheat the Transfer Paper to help stabilize it, by removing moisture?

Maybe moving the sandwich from the Laminator directly into Hot water bath? But I think the Toner has to cool a little before it can be disturbed.

I think if I was working on lager or a more conventional size circuits, all of this would not be a problem, maybe only very thin lines are susceptible to the problem.

I am still working on my HB Double Sided PCB Methods - but so far, the Magic still alludes me.

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Sunday, March 20, 2011

RTC DS3231

I have recently been made aware of an interesting temperature compensated Real Time Clock chip, the DS3231. This information is archived here for my later use.

The chip contains its own Tuning Fork Oscillator element, and therefore very few external parts are needed. The chip was introduced in 2005 and available from Mouser for about $10.00 ea.

From the datasheet, the DS3231 provides:
  • Accuracy ±2ppm from 0°C to +40°C
  • Accuracy ±3.5ppm from -40°C to +85°C
  • Battery Backup Input for Continuous Timekeeping
  • Operating Temperature Ranges
  • Commercial: 0°C to +70°C
  • Industrial: -40°C to +85°C
  • Low-Power Consumption
  • Real-Time Clock Counts Seconds, Minutes, Hours, Day, Date, Month, and Year with Leap Year Compensation Valid Up to 2100
  • Two Time-of-Day Alarms
  • Programmable Square-Wave Output
  • Fast (400kHz) I²C Interface
  • 3.3V Operation
  • Digital Temp Sensor Output: ±3°C Accuracy
  • Register for Aging Trim
  • Active-Low RST Output/Pushbutton Reset Debounce Input

For my use in my Beacon Projects; the programmable alarms and once-per-minute interrupt output could be used for the two minute WSPR timing requirements, or accurate QRSS start of signal timing. The Temperature Output could be used for remote environmental sensing, maybe for balloon payload data.


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Saturday, March 19, 2011

Macro Lens

In recent months all of by Blogged photos have been taken with my HTC Droid Phone Camera. But it is lacking a little for the small project that I enjoy. Very close-up photos can not be taken with the standard (almost pin hole) style of lens.

I found on eBay a Magnetic stick on Macro Adapter for phone cameras. If you search on ebay, the same lens can also be purchased for less than $10.00 (with shipping) . I decided to give it a try.

The lens comes with a Sticky Back Metal Ring which is placed on the phone camera. The lens has a similar strong magnetic ring that make it easy to attach/remove to/from the camera. When installed, the lens stick out about 1/2 inch.

The following are some of my initial test photos. The shooting stage is a paper towel backdrop on my bench, and the lighting was supplied via overhead florescent tube fixtures about 3 feet away. I think more light from each side would make for better results - I will have to work on that.

This new photo is of a previous (failed) Audio Amplifier project. The macro lens distorts the image a bit, and the near focus (depth of field) could be better, but it was not obvious there was a problem when I took the photo, the camera was trying to auto focus and does not always get it right.

This is a photo of my attempt to create the smallest traces that I could with the Toner Transfer Method. This coil and variable capacitor resonates at 10.14MHz. This photo is planer and therefore did not distorted.

The next photo is of my very early attempts to use solder paste and oven re-flow soldering, the board 1 x 1/2 inches.  This board has been stored with other examples for a long time. Under close full photo inspection, it is obvious the solder paste has flattened and now would short-out if used.

Click on the images, to see the raw camera image detail and photo size.

And of course, this is a test photo of my Partner in all my adventures, Tess my Dog, she is on the work bench next to the computer (Macro not necessary here). She would rather we be outside playing ball.

Tess
(5 years old)

It will be fun trying different staging and light set-ups for the photos.

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