PUT shift register (CB20719E)

This shift register was found in old documentation. PUT is not a common component today. The circuit is low speed.

Rocket Altimeter (CB25357E)
Today we have more compact solutions. This is from a Radio Electronics magazine from October 1990....
Band rejector active filter (CB7405E)
This filter was found in Texas Instruments documentation from the 1980s. The circuit uses a common...
Transistor test (CB22545E)
16 commercial test circuit for tubes and transistors appeared in Radio Electronics magazine in...