Triac Heating control (CB21372E)

We found this circuit in a 1966 RCA manual. The integrated circuit is unusual, and the Triac must match the load.

Crystal Radio (CB21207E)
This crystal or galena radio was found in documentation from the 1990s. The earpiece must be a...
Hand Dryer (CB18786E)
With this circuit it is possible to use a common hair dryer as a hand dryer. The circuit is timed...
LM3900 Rectangular Oscillator (CB25179E)
This 1 kHz oscillator uses a Norton LM3900 operating system. The frequency depends on C1 and R1...