AB4YD Amateur Radio Page


Posted on Feb 5, 2014

This project was inspired by a series of QST articles by Hayward, W1PH. I based my rig on his April 1962 article, `Have You Tried 160 Lately `. I liked his simple, single band rig. I thought his use of 6V6 tubes, along with regulated voltages, to be a simple but stable alternative to being `rock bound`. You can read about his `coffee can` VFO, in


AB4YD Amateur Radio Page
Click here to download the full size of the above Circuit.

the August `49 and Sept `51 issues of QST. However, I ignored his approach to mounting the VFO part of the circuit in a sturdy coffee can, and just put all of the circuits onto the same chassis. It worked, but it was very microphonic, and this made it difficult to operate. I eventually chose another route for the VFO, and used a separate chassis for the VFO circuit. Along the way, I also changed the VFO tube to a 6C4, mainly to reduce problems related to heat. The output was very low, so I added a 6AC7 stage. I also went to a 1/2 freq VFO, and doubled the frequency to 80M just in front of the 807 final. I am pretty happy with the stability of the VFO. The output from the 807 seems a little low, but perhaps it is due to my low B+ and 250V screen. I get about 20 watts into my 50 ohm antenna, even after going thru my half-wave output filter. All in all, it was a fun project.




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