This circuit, with printed circuit board included, is from a Radio Electronics magazine from July 1971. The SCR can be any equivalent of the 106 series.
Operatives used in this 80's configuration are not common today, but it is valid for modern...
The 5 outputs of the internal 4018 integrated flop flops can be used simultaneously for the...
This voltage-controlled potentiometer using an LDR was found in an English documentation. LDR is...