Found in Motorola's 1965 manual, this full-wave dimmer controls a load that depends on the used SCR. The trigger element is a neon lamp.
Today we have more compact solutions. This is from a Radio Electronics magazine from October 1990....
This filter was found in Texas Instruments documentation from the 1980s. The circuit uses a common...
16 commercial test circuit for tubes and transistors appeared in Radio Electronics magazine in...