So now comes my latest effort in the form of a short wave receiver. I pinched the schematic Dave devised for his #58 set as he decided to switch from a crystal detector to a 1625 tube set. And it does perform well indeed! The selectivity is way better than any short wave thingy I've managed to build and the 6:1 vernier drive from Dave makes sharp tuning a snap. And, yes, it is sensitive to boot! I have a 350' antenna and I receive 12 stations without even adjusting the band spread capacitor. The only problem is they are all religious programs except for the one Mexican station.
I used a piece of 2" AirDux coil cut to 10.3 µH and combined that with an 81 pF variable capacitor. This allows me to tune from about 6 Mhz to 10 MHz. I used a 10 pF band spread variable capacitor ... actually it is a 35 pF but I wired an 18 pF fixed capacitor in series and it works great. All of this came with the help and advice of Master Dave. Now if he would only devise a short wave schematic that would receive something other than religious programs.......
It is a regenerative receiver that operates on a single 12 volt DC wall wart converter which comes with the set. None of the inconvenience of a 'B' voltage and 'A' voltage mess or even a separate filament supply. Everything is neatly provided by the wall wart (did I mention that it comes with the set?) .
The top and front is clear acrylic (3/16" thick) and the sides, back, base and knobs are padauk wood finished with flattened lacquer. No stain needed on this incredible material. Brass binding posts for antenna and ground connections are mounted behind the 1625 tube. You might notice that the brass plate cap and all three knobs are cut flat on top which gives the set a 'crew-cut' or a 'flat-top' look that I like a lot.
Please e-mail me for price and availability.