This stereo circuit is from Japanese 1960 documentation. The circuit was originally designed to work with a tube amplifier, removing power from it. The transistors are germanium.
This is the power supply circuit for the amplifier in the previous circuit. The source is...
This version operates in the opposite way to the previous one, triggering when light falls on the...
The sensors in this circuit are NTCs and PTCs that work in a differential way by directly...