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 configuration appears elsewhere on this site. We obtained it from a 90s Radio Electronics, based...
This circuit is from a Fairchild digital clock module shown in the March 1977 issue of Radio...
This good power amplifier, a few tens of watts, is part of an article in the December 1972 Radio...