Speaker output reflex receiver (T1653E)

Found in a 1924 publication, this 2-valve receiver has a speaker output. Power comes from several batteries. Information about the coils is given.

| Clique na imagem para ampliar |

5-stage digital sine wave generator (CB24477E)
We found this circuit in a Radio Electronics magazine from November 1976. The clock frequency is...
Capacitive Antenna (CB13646E)
This circuit was obtained in a manual for radio amateurs from 1975. It is a circuit that allows the...
LED Test Using the Oscilloscope (MSB008)
The LEDs act as diodes, so if good they will show the same characteristic curve. Arrangment shown...