This variable 1 A power supply with voltages up to 30 V was found in an article in June 1986 Radio Electronics magazine. The 723 IC is well known to magazine readers of the time and even today.
This circuit uses reed switches as sensors. We found it in a 1992 documentation. A float at a...
One of the problems with analog multimeters is the non-linearity of the resistance scale. This...
I found this circuit in an old English magazine from 1979, but it can be easily assembled with...