We found this balanced modulator circuit for DSB and possibly SSB transmissions in US 1980s telecommunications documentation. The diodes can be replaced with equivalents.
This circuit uses high voltage transistors to provide direct power from the 110 V power grid or a...
This circuit was designed to work with the previous one in triggering a relay by the sounds picked up...
This circuit was suggested by Signetics in 1980s documentation. The circuit makes use of the...