This circuit is from the time when photos were revealed in darkrooms. We found it in a 1968 Electronics World. The circuit can be used for other purposes.
This active crossover filter was obtained from the component manual used. Below is the performance...
This circuit is from an 80's documentation. It makes use of two SCRs with current capacity...
This interesting idea was found in a 1983 publication and is very simple to analyze, according to the...