Guys,
I designed test equipment and then more stuff to test the stuff we were
building, so here is what I did for the test floor stations. The power had
2 settings, one for first power had 25 Watt Christmas tree bulbs in series
and a bright light meant trouble, but at least saved the smoke routine.
The second setting was straight power for the final test.
Simple?

Bill Baka

That be called a Dim Bulb tester. Not referring to the user but the device.
See hw to make one here at:

http://www.antiqueradio.org/dimbulb.htm

Paul P.