This type of answering machine was common at the time this circuit was published. Using two tape recorders, it was published in the June 1986 issue of Radio Electronics magazine.
Found in Popular Electronics from 1969, this circuit uses a neon lamp from the time that had...
This receiver was found in the Radio Electronics magazine of March 1953. It tunes to the medium wave...
The figure shows how to use the XR2206 to generate sinusoidal signals in a different way. The...