Signal Tracer and Capacitor Tester (T1241E)

This mains powered two-in-one instrument was found in a Radio Craft from March 1948. The headphone must be high impedance.

Electronic Die (CB12266E)
By pressing and releasing PB1, only one LED is lit, drawing a number from 1 to 6, as in a die. The...
Sampling and Holding Circuit IR5321S (CB14378E)
We found this circuit in the National Semiconductor Linear Applications Handbook of 1994. The...
Battery and Battery Eliminator (CB1406E )
The transformer inf this circuit is a 6 or 9 V unit and diodes 1N4002. The filter capacitor is 2...