We found this circuit in the Radio Electronics magazine of December 1972. It generates signals in 6 frequency bands, being indicated for experimental applications with TTL circuits.
This good quality stereo amplifier was found in a Japanese publication from the 1960s. The circuit...
This circuit allows you to use the parallel PC interface to control LEDs. The circuit was found in...
This circuit, with printed circuit board, is from an article in Radio Electronics magazine from...