#245: Old Tech: The Wadley Loop Superhet Receiver

w2aew | #245: Old Tech: The Wadley Loop Superhet Receiver - Yaesu FRG-7 Example @w2aew | Uploaded September 2016 | Updated October 2024, 30 minutes ago.
The Yaesu FRG-7 general coverage HF communications receiver utilized an interesting superheterodyne architecture called the Wadley Loop. It is a drift cancelling circuit that dramatically improves the frequency stability of the receiver by compensating for, or more accurately, cancelling out the drift of the 1st local oscillator (LO). This video takes a look at how the Wadley Loop works, and shows some example signals from within the FRG-7 unit.

Notes from this video:
qsl.net/w2aew/youtube/WadleyLoop.pdf

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