Early radio receivers worked on a principle called Tuned Radio frequency (TRF), patented in 1916. They weren’t very easy to use, requiring each stage to be tuned to the same frequency (until ganged ...

The first television receivers were designed to receive BBC transmissions from the Crystal Palace transmitter in London. This was, incidentally 405-line all-electronic television, then regarded as ...

This radio avoids the implementation problems of ZIF, but has more parts and is more expensive to produce. Thus, designers will have a tougher time adapting single-band superhet radios for dual-band ...

Marked: (Plate) "Radiola Superhetrodyne Model AR812 No. 145451, Range 220-550 Meters. Patented: 1/21/08; 3/5/12; 10/6/14; 7/3/17; 10/22/18; 6/27/20; 6/8/20; 2/18/16 ...

IIIF provides researchers rich metadata and media viewing options for comparison of works across cultural heritage collections. Visit the IIIF page to learn more. A "super-heterodyne" radio receiver ...

If you cultivate an interest in building radios it’s likely that you’ll at some point make a simple receiver. Perhaps a regenerative receiver, or maybe a direct conversion design, it’ll take a couple ...