The gain of this step is controlled by the feedback circuit depending on the strength of the input signal. The circuit will operate with modern general-purpose transistor.
We found this circuit in the On Semiconductor thyristor manual. He makes use of a triac and a PUT....
This 80's circuit uses a light-sensitive SCR or LASCR and a one-sided silicon switch SUS, uncommon...
Using an RCA CA3018 as a base, this circuit has a sensitivity of 2 Mohms per volt. The circuit is from a...