We found this sophisticated meter circuit in an article in Radio Electronics magazine from June 1959. The article taught how to assemble it. Transistors are common types at the time.
In the figure we have the typical configuration of a sinusoidal audio oscillator with twin-T. The...
This circuit was found in a 1969 US documentation. It provides a signal that can be externally...
We found this adapter in a 1970s American documentation on instrumentation. It is suitable for analog...