The integrated circuit used in this trigger is uncommon today. We found it in a documentation from the 70s. The circuit operates with signals up to 50 kHz.
We found this circuit in a 1977 factory documentation. The operational amplifiers can be 741 and...
This circuit with regenerative action was found in the June 1986 issue of Radio Electronics...
Equivalent FETs can be used according to the frequency of the crystal which can be up to a few...