This AM receiver circuit is based ob the IC ZN415 introduced by Ferranti. This IC is an improved version of the early ZN414. It is a complete AM radio receiver and does not need IF transformers and ...

A crystal radio is basically a high Q resonator tied to an antenna and an envelope detector. These days the envelope detector is a point contact diode such as a 1N34 Germanium diode. The resonant ...

This article is intended to introduce the beginner to the interesting and challenging art of high frequency radio design. It is also intended to entice the seasoned professional to take a deeper look ...

VARIABLE condensers are now so commonly employed in radio receivers to tune circuits including a constant inductance that the use, some years ago, of variable inductances or variometers with fixed ...

Marked: "Oriole Jr. / Trinum Circuit". On plate: ORIOLE Receiver / Model 90 / Serial 402 / Warning: Trinum Circuit Used in this receiver is patented and infringement will be prosecuted / W-K Electric ...

As the roaring twenties came to a close, radio technology would continue to evolve with significant improvements to consumer sets, particularly in the area of shortwave reception. Read my past ...

Full-duplex radio communication usually involves transmitters and receivers operating at different frequencies. Simultaneous transmission and reception on the same frequency is the Holy Grail for ...

Marked: "Radio Receiver / Type 998 SE / Serial No. 39N / [lambda] 50-600 meters / Made for Bureau of Steam / Engineering by National Electric / Supply Co., Washington DC. / Req. No. 553SE Cont. No.