Testing of thermistors and SCRs (CB21391E)

This circuit was found in an old American manual. It is intended for testing SCRs and thermistors using indicator lamps.

Simple blinker (CB6759E)
P1 on this Radio Shack circuit is a 6 V lamp with current up to 500 mA depending on Q2. The...
Touch Alarm (CB17032E)
This simple touch alarm, found in a 1995 documentation, uses common components and a triac to...
Micro Voltage Regulator (CB1577E )
With the micro voltage regulator shown in the figure, we can design a power supply for small...