This temperature control was found in General Electric documentation from the 90's. The circuit uses a 10k ohm NTC sensor as a sensor. The triac must be in accordance with the controlled load.
This crystal fundamental frequency oscillator can operate at frequencies up to a few tens of...
This circuit produces signals in the range of 200 Hz to 2 kHz. We found it in the magazine...
This circuit is from a 1964 Electronic Design, appearing in this section and website with...