Published by Philips in 1965 documentation, the sensor for this circuit is a common LDR. The transistors are general-purpose types from the time, only TR3 is a power type according to the load.
April 2017 - Littelfuse's new two-way discrete TVS diodes for protection against ESD up to 30 kV...
Found in an English documentation from 1989, this circuit is intended for equalization of cassette...
We can also use the 4011 on this CMOS circuit that makes use of a crystal headset. The power...