and a beautiful TRF Receiver.
1) The Jones "One-Tube" Regenerative Receiver. This particular schematic shows a 1G6 tube instead of the original #19 or #53 tube. I have not yet built this receiver, but intend to do so ASAP. I will post pictures and a better description when I have done so.
From schematics of other regenerative receivers I have recently seen, this same basic circuit can be used with two separate triodes, or a tetrode or pentode as the detector stage. A 12AT7 should also work quite well in this circuit. Any dual, low, or medium-mu, triode will work just fine, provided it can be made to work at fairly low voltages. LOW MU triodes make the best regenerative receivers, since they slide very smoothly into and out of regeneration, whereas the higher mu triodes become quite "touchy" near regeneration. Furthermore, if you use a 22 megohm resistor for the grid leak and about 20 pfd for the grid coupling cap, you will find this circuit will be both more selective and a bit easier to operate
2) Walt Turansky's, KW7WT, 3 tube Regenerative Receiver. This is the old 0-V-2 design. Walt says that this receiver will hear everything his more modern SS rig will hear, and it is a really classic design. Although V2 and V3 could be replaced by either two 1H4s or a single 1G6, I have not yet found a more modern equivalent for the #32. However, Antique Electronic Supply, has this tube. This is a low-C design, which should be a bit broader and easier to tune than the previous circuit.
3) An FET version of the 1-V-1 Regenerative Receiver, designed and built by C.F. Rockey and shown, as one among many, in the Lindsay Publishing Co. book, "Secrets of Homebuilt Regenerative Receivers", available from Lindsay for $9.95. Although I much prefer tubes, this one should satisfy those who may want to build and use a more "up-to-date" version. You will note that this receiver can use the same coil data as the Jones "1-tube" regen shown in #8 above. It most closely resembles the Jones "Gainer" shown in the Jones book, "The Radio Amateur Newcomer" mentioned above.
4) ZL2JJ's truly beautiful homebrew TRF receiver, designed and built by ZL2JJ, S. P. Byam of Waverly, New Zealand. This is an excellent example of what one can accomplish by careful thinking and even more careful construction. I hope this might be an example and an incentive for others to do as well.
5) RCA designed "Battery Operated Short Wave Receiver" . This is a TRF receiver which uses battery tubes which require 1.4 volts for their filaments. This design is very similar to RCA's A.C. operated, "Regenerative Shortwave Receiver". In addition to the scanned .JPG, I have also included .PDF versions of both the Battery Regen and the AC Regen. These receivers are shown in the "Circuits" sections of RCA Receiving Tube Manuals, RC-14, RC-15, and RC-16, and possibly others.
6) The 12AT7 Regen
Here is a copy of an article from an old electronics magazine. The .JPGs that make up this article may be too big to print directly from your browser but give it a try anyway. This article, and another about a companion transmitter, were made available by Mike Silva. Start here, or above.
7) More regennies.