I've seen a lot of small AM transmitters described in this forum - all very neat and innovative circuits. I was just wondering if anyone had ever seen this article in the 1961 Electronic Experimenter Handbook? This article was written by Lou Garner and it's a very interesting small AM transmitter circuit using a crystal microphone. I've attached a couple of low-resolution scans of the article in case anyone is interested. He uses a 12AT7 mic-preamp circuit feeding a 50B5 used as an oscillator/doubler. The oscillator coil is a 455KC IF transformer (thus the doubling needed to hit the BC band). Obviously, the IF transformer would be the toughest part to find, but I thought the article and design was interesting.

I always enjoyed Lou Garner's articles and the Solid State section of the Popular Electronics magazines in the 1960's. I would be interested in anyone's comment on the circuit.

Thanks
WD5JWY

Well that's interesting and likely performs fine for it's intended use... It's a variation of old phono osc, will be plagued with FMing when broadcasting music...

First time I've seen a 50B5 used as a rectifier, wonder why he didn't use a 50DC4??? I looked on a Feb '60 T-S price list and it's there(was reg in '58) also cheaper than a 50B5...


Tom