Originally designed for WWV (Standard Time Station) signals, it lets 1 kHz tones pass by rejecting the 440 and 600 Hz tones emitted by the station. The circuit is from a 1964 Electronic Design.
This circuit is based on the 3 A LM350. The circuit is from Popular Electronics having a...
To operate with high input voltages using a 3-terminal voltage regulator such as the LM340-15, we...
The voltage gain of this circuit is 1,000. This gain is given by the ratio between the 10 M ohm...