We found this circuit in the Linear Applications Handbook of the 1994 National Semiconductor. The transistor must be a high voltage type and the LM3900 power supply must be symmetrical.
This circuit is from a very old publication, from the 60s. It uses germanium transistors from the...
This complete video game circuit was found in the May 1978 issue of Radio Electronics magazine. The...
Found in documentation from the 70s, this TTL circuit is based on optical sensors made with LEDs...