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This is my version of Dave Benson's NE40-40 transceiver, but I did not build the transmitter section, at least not yet. It is scratch built ugly, using ground out islands. I found the schematic in QRP Power, and built it according to the original schematic, without the mods, except for a few things at the input (what was on hand), so I could get a good idea of how the original receiver performed, and sounded. Dave's design only has two xtals in the IF, and after hearing how it sounds, and filters out the other side band, I think it's perfect! I have a YouTube video, here , so you can listen, and see how nice this little rcvr sounds. I used a ten turn pot and a junk box varactor diode, which gave me abt. 90 kcs of tuning range! click to enlarge
The layout is clean and free of dc wiring, as those (few) connections come up from the bottom of the board, as seen below.
Below: Testing the 3Mcs Colpitts oscillator.
After tinkering around with various components for the vfo, and was satisfied with its stability, I as usual, settled for a combination of silver micas, polystyrene, and npo's. I then annealed the oscillator coil in boiling water, like I did with my W7EL xcvr, which has proven to increase its stability even more. After all was said and done, I lit a candle and dripped hot wax over the coil, to keep it even more rigid. The wax was not in place, when the pictures were taken. Click for a better picture.
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