This circuit is from a March 1967 Radio Electronics. The circuit applies to general purpose SCRs such as the TIC106, C106 and others. The test is done by increasing the gate voltage to the trigger point.
We found this interesting configuration in a 1976 technical documentation. Equivalent diodes can...
Indicated by the Maxim Engineering Journal in the 90's edition, this circuit uses only one...
The gain of this circuit is given by the value of R1 that depends on the current in the...