This circuit was obtained from a 90s Radio Electronics. The value of R1 determines the scale according to the table next to the diagram. The power suppley must be symmetrical.
We found this circuit in a publication from the 1970s. It produces intermittent clicks on a...
We found this circuit in the 1994 National Semiconductor Linear Applications Handbook. The circuit is...
This circuit is from 1977 Radio Shack documentation. The circuit modulates an LED (which can be...