This circuit, which can serve as a reference for restorations, was found in the October 1989 issue of Radio Electronics magazine. The circuit uses a 5-digit display and a dedicated integrated circuit.
The transmitter shown can reach around 100 meters depending on the location and sensitivity of the...
This circuit converts a positive CMOS supply voltage to a negative one. We found it in a 90s...
The circuit shown in figure 5 generates square signals based on a transconductance operational amplifier...