This circuit was found in the October 1989 issue of Radio Electronics magazine. It drives an auxiliary relay with the call signal for a possible louder bell.
This circuit was obtained from an English magazine from 1976. The circuit operates two LEDs and...
Found in a publication from the 60's, this power supply has no regulation, but only current...
This circuit can use the LM148 and its more modern equivalents, generating a sinusoidal signal whose...