An oddball radio project

[GB46]

I'm just wondering whether anyone remembers a project published in Popular Electronics way back in the sixties. It was a transistor radio supposedly powered by RF instead of batteries. The RF was supposed to have been received by a crystal detector and converted to DC, which in turn powered the transistors. In effect, it was actually two radio circuits in one package; you tuned the crystal set to a strong AM signal for power, then tuned the transistor radio to your desired station. I suppose there would have had to be a local AM station nearby to supply enough power. Being kind of skeptical, I never built the thing, but maybe someone here remembers the project and even built one.

 

[majoco]

It'll be in here somewhere....

POPULAR ELECTRONICS: Consumer Electronics and Experimenter magazine

Popular Electronics Magazine: 1954 through 1982 Consumer electronics and experimenter publication. All issues available for reading or searching.

worldradiohistory.com

 

[WB9YBM]

You might want to check with your local library; many have old magazines on microfilm or other similar formats...

 

[GB46]

It'll be in here somewhere....

POPULAR ELECTRONICS: Consumer Electronics and Experimenter magazine

Popular Electronics Magazine: 1954 through 1982 Consumer electronics and experimenter publication. All issues available for reading or searching.

worldradiohistory.com

Thanks, Martin. I've started searching there, but with the disadvantage of not remembering what the project was called. I also can't come up with a suitable search term to describe it. All I can remember is that the gadget had two tuning dials, one for each of the two receivers.

 

[GB46]

You might want to check with your local library; many have old magazines on microfilm or other similar formats...

Thanks. Well, our local library is very limited, and also contains the town's museum. The building's name is very appropriate: "Library Museum", since the library portion is more like a museum documenting the age of printed books, since almost everything is web-based these days. Then there's the difficulty of accessing their collection during the pandemic.

Anyway, I'm currently searching the Popular Electronics online archive, as suggested above by Martin.

 

[GB46]

In the meantime I've found this on Wikipedia:

A carrier-powered radio is a batteryless radio which "leeches" its power from the incoming electromagnetic wave. A simple circuit (very similar to a crystal set) rectifies the incoming signal and this DC current is then used to power a small transistor amplifier. Typically a strong local station is tuned in to provide power, leaving the listener free to listen to weaker and more distant stations.

They show no circuit diagrams or images, however. Searching Google on "carrier-powered radio" merely brings up sites that quote Wikipedia, but at least I now know what to call the thing!