Photometer for enlarger (CB8342E)

This circuit for old photo enlargers was found in a 1970s RCA manual. The components are from the time, but modern equivalents can be used.

| Clique na imagem para ampliar |

Bistable CMOS (CB15699E)
The circuit shown in the figure allows a pressure switch to be used to turn a load on and off in a...
Square and Triangular Generator 3900 (CB19707E)
Raytheon's used integrated circuit is no longer common today. The circuit was obtained in a...
64 us pulse delay (CB6659E)
Found in a 1968 Electronic Design, this circuit makes use of an unusual ultrasonic delay line...