We found this circuit in an English publication from the 1980s. The circuit uses current components and can be tuned for frequencies between 300 and 1500 Hz.
The purpose of this circuit is to excite a TTL input with lz pulses. The phototransistor can be of...
This circuit was found in the RCA Power Transistor manual from the 70's. The circuit uses power...
We found this circuit in a technical documentation for the National Semiconductor LM3909. The...