This circuit was found in an American documentation from 1969. The circuit is a multi-indicator with resistors typically 47 k for R1 and 100 k for the others.
The XR2206 is not a common component today, but if you have one you can build this function...
August 2016 - It can be obtained from Mouser Electronics new wireless 3W transmitters from RTD to...
This circuit for a frequency of 1 kHz uses a symmetrical source. Other operational circuits can be...