E)
This circuit uses a reversible double contact relay to obtain the trigger lock with the unijunction pulse. The relay must be of the sensitive type with at least 150 ohms of coil.
This circuit was found in a 1967 Raytheon manual. The transistors are from the time. Equivalent modern...
This circuit was published in a 1979 magazine, but it can still be easily assembled as the...
The circuit presented generates short pulses. This configuration was found in a publication from...