This circuit allows you to adjust the balance between channels of a stereo amplifier. The circuit makes use of an analog indicator with zero in the center of the scale.
This circuit triggers the LED when the monitored battery voltage drops below 9 V for 12 V...
We found this circuit in a Radio Electronics from January 1967. The SCR is already the C106, which...
This power source with silicon diodes at a time when valves were still used was found in Radio...