This signal multiplexer circuit for early low-frequency oscilloscopes was found in the May 1977 issue of Radio Electronics magazine. The circuit requires a symmetrical source.
This circuit was found in a 1977 Radio Handbook. The ports used are CMOS like 4001 and the...
I found this Vox circuit or acoustic receiver as it was originally called, in a 1973 publication. The...
Found in RCA documentation from the 90s, this bass and treble control uses an operational...