I want to build a one or two tube radio, using parts that are in an old semi junk marker generator. Available, two 12au7 tubes and one 12ax7 tube. I have variable capacitors, an assortment of small ones. I can wind a coil or two. My thought is an RF amp and a regen detector, and a stage of audio. I built a one tube receiver back in 53 or 54, and then a project radio soon after, from a popular mechanics or popular science magazine the project used 3 tubes, as I recall, a detector, an audio output and a rectifier. Had plug in coils to change bands I had a lot less knowhow on troubleshooting back then, and it never worked. May have been a bad filament in the 35z5 it used as rectifier, I know that now. used a50l6gt for audio, and a 12 volt filament triode of some kind that was common way back.
I know tons more now, having held a commercial radiotelephone, 2nd class, then general class, and now hold a general class amateur radio license. And can troubleshoot. I know the two basic kinds of regen detectors, but don't recall the values of parts at this time. I am limited in parts, especially resistors, other than a decent assortment of 1/4 watt resistors. I want to use a 600 ohm headset, being as i have a number of them that seem to all be in good condition. Were ones tossed by a local school. I need a few pointers on this part, as well as resistor values, and coupling caps. I do have a drawer full of ceramic disc caps, don't recall the value, don't feel like going to check now, but should do well the old generators as power supply should serve well. I know one can sub parts, and use parallel parts in some instances. if someone can help with a few schematics, would be very thankful. I am limited in getting parts, due to little income, and being a long ways from suppliers, not to mention rather disabled due to COPD.
Anyways, I could possibly design something by trial and error, just not up to it a lot of the time. One nice thing with tubes was having a lot of leeway to work with. Antenna no big deal, as I have a dual dipole antenna for 75 and 160 meters, which will also do well for AM broadcast. Can also run an end fed wire if needed...
I could use some parts like 9 pin mini tube sockets, rather than trying to use the existing PCB in the generator, as the ones in it are not located in ideal spots. But I could try and salvage some from a junk AC/DC radio...
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