This circuit uses two diodes in a doubling configuration to receive medium-wave range signals. The phone is crystal. We found it in a 1968 American documentation.
This circuit was found in a NASA documentation from the 1980s. Component values are application...
This polarity inverter circuit for voltages down to about -12 V was found in the December 1992...
This high-Q low-pass filter was found in the October 1990 issue of Radio Electronics magazine. The...