This telephone recording circuit was found in the June 1979 issue of Radio Electronics magazine. The components are common at the time and the power is supplied by the power grid.
This circuit is basically the same configuration as the previous one with a power stage with...
Found in a 1969 documentation, this circuit for the 20 MHz band does not use a transformer. The circuit is...
This circuit can provide a voltage of up to 900 V depending on the input voltage. The diodes must...