The circuit board it small: 3.5"x2.5". All the components come with the kit, with the exception of plugs needed to mount the PCB in a box. Actually, the kit was missing an integrated circuit socket (I found one at Radio Shack), and had two extra transistors..

It had been a long time (27 years) since I had finished electronics school. I had never soldered on a double-sided circuit board, but it turned out to be fairly easy. I just made sure I had a nice solder joint on both sides. The resistors went in first, then diodes, and so on, mounting the shortest components first, finishing with the talents. This way, you can use a piece of foam to press the components side onto it while you solder on the other side. This keeps the components near the board. One exception is the transistors. You don't want to overheat them, so it is better to mount them a little further out. The final output transistor is not put in until the kit is finished and tuned. Transmitting without a tuned antenna could destroy that component. Winding the coils was a pain. You need to make sure you count the turns carefully. One turn is every time the wire goes through the center. The parts are so small, I needed to wear reading glasses!

When all the components were in, I cut off the plug from old headphones and soldered them in. I also soldered a long wire as an antenna to test reception. It worked! I did hear faint morse code and SSB voices when tuning. The oscillator frequency however seems to be wrong: 14,063.2 Mhz instead of 14,060. I am not sure if there is a problem with the frequency counter, or I am that far off. The morse code keyed works too, so I have a working radio, except for the output frequency. I will need to find someone with an HF ham radio to check my tuning. I am investigating a way to fix the frequency problem and measure it accurately for sure. My progress will be posted here soon, as well as the mounting of the project in a box. Now I just need to learn morse code; darn, why didn't I think of that?

Update (May 27^th): I think I am going to ditch the DC20B. I have a box for it, and should complete the build, but after that, it's going away. I can't get it on frequency, and I am not the only one... The Rock-Mite kit should arrive this week. I can't wait to build it. Look for the article!

Update (May 30^th): Well, I gave it one last try.. Changed C36 to a 100pF, and C29 to 47pF. It worked! Now I get 14,059.72 on transmit. Receive goes from 14,060.16 to 14,060.32, a perfect 600Hz offset. The problem is the receiver, which has no selectivity. I receive Chinese, French and Spanish commercial radio stations, but little, faint CW signals. Maybe the problem comes from the wire I use as an antenna, which isn't tuned. I will try a tuned dipole during the day and see if I can get clear CW (morse code). I boxed up the DC20B in a nice Hammond cast aluminum box. I made a hole in the cover to tune CT1 and glued a piece of coax outer insulation so that I can't touch anything with my screwdriver upon insertion.. The box is a little big, but it looks good and as though it would survive being run over by a semi-truck.. I might make another hole for access to CT2 and add an RCA plug for a frequency counter (for tuning).

Still waiting for the Rock-Mite (shipped today).
Elecraft K1 arrives tomorrow (June 7th).

Total length very-top to very-bottom is 58". Width center-to-center is 2". Gap is about 1-3/4". See the Ham-Universe articles (1 & 2) for exact measurements.

It is easy to calculate dimensions for other frequencies:

• 3/4w : 8415/F-mhz.
• 1/2w : 5610/F-mhz.
• 1/4w : 2805/F-mhz.
• Feed point : 10-20% of 1/4w.

The gap is taken off the 1/4 wave element...

The PVC Ts need to be reamed with a 5/8" drill bit so that the copper tubing can go through. I used a bit of WD40 to slide them down. Between the two Ts, I epoxied a 1" piece of 1/2" plastic tubing. There is one "H" PVC support assembly on the top portion and one on the lower portion, right next to the end cap.

I am not sure that using a plastic electrical junction box was a good idea for the feed point. Since I have not received my SO-239 socket yet, I must hold off on the electrical connection. My concern is that soldering will be difficult without burning the plastic box. I might have to use sheet-metal screws. Tunig might not be easy either, since the best SWR is obtained by moving the feed point up and down, between 3 and 4" from the very-bottom. Maybe I should have used PVC Ts, like for the two support "H" assemblies. They can be split in half, then the coax soldered after finding the best feed point. Once epoxied, it would look fine. I do like the look of my electrical box though, and if it works fine, I will be happy with the results.

Total building time was about an hour. Everything came from the hardware store, except the SO-239 connector. Soldering turned out to be pretty easy. I sanded the parts and used flux paste before heating up the assembled parts with a torch. Once the parts are hot enough, you put the solder on, which flows in the joint, following the flux. Cost could have been as low as $30, but I spent about twice that much, not counting tools (hacksaw, drill bit, epoxy, solder), which you might have already. If you are starting "empty handed," plan on $100. While it can cost more than a factory-made antenna, you get the satisfaction of building something yourself, which might be actually sturdier than a store-bought model.

Stay tuned for the finishing touches (painting), electrical connection and reception testing.

Thanks to Richard KE5FXU SK at hamuniverse.com for the article!

Update, April 11th:

Finally, I got my SO-239 plug. Drilling the PVC box was easy. I didn't even use my drill press. It only took me a few minutes by hand! Holes are one 5/8" in the middle, and four 1/8" around. I drilled in the middle of the lid, hoping I would have enough leeway to adjust the SWR by moving the contact in the box along the tube. First, as I suspected, I could not get the tube hot enough to solder the center of the coax to the copper tube using my 30w soldering iron. I solved the problem by heating up the tube with a Zippo under it while I soldered on top! It worked really well. I did the same to put soldering points in the box, every quarter inch or so. The zippo was placed an inch from the box. I was worried about melting it, but these electrical boxes are pretty heat-resistant. Sorry about picture quality:

It's a bit ugly, but inside the box anyway..

Reception works great. I was able to listen to a conversation tonight on a distant repeater that I simply could not hear with the HT rubber antenna. I get three extra signal bars with the Slim Jim. I got a cheap VHF/UHF digital SWR meter from Hong-Kong, which seems to work fine, but for the connectors which are of "N" type.

Update, May 1st:

I painted the antenna sort of a flat olive-drab color for stealth. I can easily hoist it up a tree and it blends in very well. SWR varies from 2.4:1 on the lower part of the band, to 1.8:1 around 146Mhz, and remains around 1.4:1-1.5:1 from 146.5 up. I used a ferrite RF choke kit from Palomar Engineers (photo below), which got the SWR down to 1.36:1 around 147.5Mhz. I much prefer the ferrite choke to the coax balun type, which looks ugly and wastes cable.