This circuit was found in Texas Instruments documentation from 1968. The transistors are from that time, admitting modern equivalents. The response ranges is from 20 to 20 000 Hz.
This circuit was found in a 1974 publication. It provides a tone indication of the temperature sensed by...
This is a simple rheostat circuit for motor control that works with voltages from 6 to 12 V. The...
This circuit with TTL compatible output was found in a 1968 US documentation. The circuit is...