This circuit is from a 1967 RCA publication. The components are of the time, admitting equivalents, including the SCR that determines the maximum power of the load.
We found the circuit of this Japanese transistorized commercial receiver in a documentation from...
In the figure we have a constant current source for Shape Memory Alloy or (Nitinol). The...
We found this circuit in the Texas Instruments opto-electronics manual. The button resets and the...