We found this circuit in the Radio Electronics magazine of May 1977. The transformer voltage is 6 + 6 V, and the current depends on the zener diodes and is in the order of 100 to 200 mA.
Found in a Philips documentation from 1968, this circuit detects the trimpot set input voltage....
This circuit is from a 1966 American documentation. The circuit uses a photo-FET, an unusual...
This is a typical application circuit of a 565 PLL. The circuit is suitable for selecting a 67 kHz...