This 80's circuitry decodes stereo signals used in analog TV at the time. The circuit can be used with VCRs to retrieve signals for passage on other media. The power supply is 12 V.
This timer with 1 second accuracy was obtained in a 1973 documentation. The Buzzer is a low-power type...
The sensors in this circuit are NTCs and PTCs that work in a differential way by directly...
The presented circuit is suggested by Texas Instruments (www.ti.com) in its Application Report...