Found in the May 1971 Radio Electronics magazine, this is the circuit for a commercial high-impedance instrument. The circuit uses 4 transistors and is powered by 2 9 V batteries.
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...