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 Zehrung - AA7L and his young grandson (I think) Brandon Williams - KF7EZE
Brandon is a new HAM and has plans to build some VHS antennas and maybe a HS dipole. Because Brandon represents a younger adult, Tess (my dog) was in heaven, Brandon was someone to play ball with.

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


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


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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