We found this circuit in the March 1999 issue of Electronics Now magazine. The indicator used is an analog type. The values indicated depend on the calibration.
We found this simple frequency meter for low frequencies in an English publication from 1978. The...
This circuit is indicated for the control of resistive loads. When S1 is opened, the triac turns on...
A VCO or voltage-controlled oscillator, which uses only two of the LM3900 amplifiers, is shown in the...