3-tube receiver 2 (T1603E)

Using known tubes, this receiver was found in a Radio Electronics from 1949. The circuit does not include the power supply.

Humidity sensor (CB25284E)
This circuit also detects IR, providing LED indication. The circuit is used to indicate humidity in...
Simple Preamplifier II (CB932E)
This circuit uses a JFET, which may be of the type BF244 or BF245 and a PNP bipolar that may be...
Digital Switch (CB17220E)
This circuit can be used to directly control direct current loads or higher alternating current loads...