This circuit can operate with different voltages, depending on the zener used. We found it in a 90s American documentation.
This circuit is indicated for measurement bridges as a null detector, thanks to the logarithmic gain...
This circuit, of a Popular Electronics of 1969 is destined to firing a gas LASER of the time. The...
This bass booster preamp is from an English publication (1966). We can mount it with more modern...