Morse Code Practice Oscillador (T118E)

This Morse Code practice oscillator was found in the 1970 RCA valve manual. Transformers are the critical components of the design.

Tunnel Diode Multivibrator (CB1339E)
The frequency of this circuit, that makes use of a tunnel diode as an active element, depends on...
Delayed Relay (CB932E)
This circuit uses a sensitive reed relay to control external loads. The time delay is given by the...
Polarity Indicator (CB219E)
This circuit uses the 741 Operational Amplifier to drive two LEDs. The LEDs indicate the signal of...