This circuit doubles the frequency of an audio signal, thus changing its timbre. The circuit was found in an Elektor from the 90s. The components are common today.
This voltage regulator for automotive use was found in a Radio Electronics from the 80s. The Q3...
This instrument was found in a publication for radio amateurs in 1973. The tuned circuit consists of...
This circuit is found in a 2005 Linear Technology application manual. The circuit monitors the High...