[R-390] Unobtainium SSB parts

[Jacques Fortin]

Perry,

If it was the relay used by W7DI (in a variant of the Capt. Paul Lee W3JHR product detector), the following one can be used instead:

https://www.digikey.ca/en/products/detail/te-connectivity-potter-brumfield-relays/TSC-124D3H-000/1128733?s=N4IgTCBcDaICoGUDCBaAjGALAEQMwAkAaABlJAF0BfIA

Or any other relay with the same specifications (especially the coil resistance and coil to contacts dielectric strength).
The trick is to replace R531 with the relay coil (See the W7DI article, Ham Radio, July 1974)
When the BFO will be powered, the relay will activate and change the audio source from the AM demodulator to the product detector output.

73, Jacques, VE2JFE in Montreal