Null Indicator (CB21930E)

This bridge was found in a Raytheon transistor manual from the 1960s. The transistors are germanium from the time.

Multitone Oscillator (CB21555E)
This circuit is from an American documentation from 1954 and is indicated for use in toys with a...
1.3 Ohm Analog Switch (CB12517E)
In figure 1 we have an application for NLAS5113, a new device from On Semiconductor...
Voice Filter with LM381 (CB25283E)
This circuit lets through the 300 Hz to 3kHz range that corresponds to the human voice. We found it...