This 300 Hz to 3.4 kHz filter was found in the May 1989 Radio Electronics magazine. The circuit requires a symmetrical power supply.
This circuit was found in the February 1990 issue of Radio Electronics magazine. The gain is given...
This 90's project shows how to use an old cassette recorder to practice telegraphy. In position A of the...
We found this 4-channel mixer in the August 1999 issue of Electronics Now magazine. The circuit can...