Found in an April 1977 Radio Electronics issue, this circuit uses the well-known XR2206. The C1 values for the various frequency bands are given next to the diagram.
This electronic roulette circuit with 10 numbers was found in a Popular Electronics from the 80s....
This circuit has a very high input impedance and a very low output impedance. We found it on a...
This circuit is from an English documentation from 1969. The circuit can be designed based on...