Following up on our recent MFJ post, SWLing Post contributor, Ron, writes:
Another thing about MFJ is they still offer the MFJ-8100 as a kit or built. This is the only regenerative receiver available as far as I know.
Mr. Jue and his guys did a couple of tweaks like limiting band coverage to insure stability, using 1/8 inch 3.5mm stereo phone jacks and use an LM386 audio IC to drive headphones or speaker.
The whole thing is in a metal enclosure to minimize hand capacitance found in most regens.
The QRP crowd likes to use the 8100 with flea power CW rigs, it’s that good.
And it’s been in production far longer than the Heathkit GR-81 or any of the Knight Kit regens, too.
Thank you for sharing that, Ron! I had completely forgotten about this little kit when someone recently asked about the availability of Ten-Tec regen receiver kits (that are, sadly, no longer on the market to my knowledge)! I might have to grab one of these kits–looks like a fun one to build.
Click here to check out the MFJ-8100K.
By the way, I also believe the NM0S Ozark Patrol regen kit is still available from the Four State QRP Group. Click here to check out the product page. It doesn’t have a metal enclosure like the MFJ, but it’s also a fun kit to build.
The MFJ-8100 is a very nice regen; I own an Ocean Hopper, Span Master, Space Spanner, Explor-Air, GR-81, and TenTec 1253, and the 8100 simply works best. I’m 71 years old, and can tune in SSB with ease. With the low prices of earbuds & headphones, it’s simple to select a set the have good audio for shortwave listening.
The 8100 is easy to modify to suit your needs. I placed some velcro dots inside, and replaced the battery with a 9v AA battery pack. I own 3 of these radios, and enjoy listening to one on my bedstand every night.
People who complain about these sets don’t spend time developing the skill to operate one. I’m a ham, and have a nice collection of classic receivers. For me, nothing beats the challenge of pulling out a weak signal better than a regen, and the 8100 meets my needs.
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give it a better vernier, add a “tone” control and it will sell for another 20+ years, on the other hand, the brit krc-2 can beat it hands down
https://swling.com/blog/2016/03/the-krc-2-shortwave-regenerative-receiver-kit/
but then from some point, it is a different kind of beast 😉
One suggestion about the 8100:
The separate antenna and ground connections are a little clunky.
A 1/8 (3.5mm) phone jack will fit into either hole so you can use a
portable wire antenna,just like any other shortwave portable.
One more thing…if you build the kit keep in mind the circuit board is
not tinned through the holes so all solder has to be done on the
surface of the board.