We found this circuit in the December 1998 issue of Electronics Now magazine. RF transistors such as the BF494 or BF495 can be used. The circuit works at lower frequencies.
This configuration with the LM111 was found in your factory manual. The circuit can be implemented with...
The double T of this circuit makes it amplify only the 1 kHz signals. The circuit can be used as a...
This car alarm was obtained in a Signetics documentation from the 1980s. The circuit uses the 555...