This 1924 receiver uses a battery for the tube filaments and a high voltage battery for the amplifier and detector circuit. The speaker is kind of high impedance era.
This circuit was found in GE documentation from the 90s. The circuit can be used as a shield for...
The output voltage of this circuit is approximately four times the supply voltage. The circuit is from...
Figure 1 shows a simple audio oscillator driven by the SCR When the sensor is closed. The circuit...