This 1965 Philips circuit uses old company transistors like the BFY51 and BFY50. The circuit is powered by 12 V and the power gain is 8.9 dB.
We find this circuit in an American 80's documentation. No further information about the...
This conventional bistable power control circuit using triac was found in the June 1970 Radio...
This old voice circuit suitable for telephones of the time was found in a Radio Electronics from...