The circuit presented uses two common transistors and is powered by the circuit being tested. The circuit is for TTL logic, since its supply is 5 V.
This circuit is from an operating manual from the 1990s. The circuit generates sinusoidal and cosine...
In this circuit the photo-transistor signal is amplified by a Darlington step and then applied to a...
When the sensor, an ordinary photo-transistor, receives light, the relay closes its contacts. The...