Indicated by Texas Instruments, this 1968 circuit measures the duration of a light pulse captured by a phototransistor. Equivalent phototransistors and transistors may be used.
This circuit was obtained from a Hands-On Electronics, an American magazine from January 1987. The...
This receiver for listening to the TR-23 phone was manufactured in Japan in the 1960s. The circuit is...
This astable multivibrator with an operational one at the time was found in the National...