In fact, this circuit from the 60's applies to photographic printers of the time, timing the lighting of a 20 W lamp. The components are from the period.
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...