Temperature regulator CIR21824S (CB21289E)

This zero-crossing switch circuit was found in documentation from the 1990s. GE's PA424 is the main element of the circuit, uncommon today.

| Clique na imagem para ampliar |

5 MHz oscillator with 250 kHz variation (CB13852E)
We found this oscillator in a documentation for radio amateurs from the 1970s. The circuit can use...
Impedance Matcher (CB15540E)
Many oscilloscopes have high impedance inputs that make it difficult to observe high frequency signals...
Optical Communicator – Receiver (CB25536E)
This is the receiver for the previous circuit we found in the December 1992 Radio Electronics...