07-08-2017, 08:16 PM
The reason why it does that is that the filament in these sets (ac/dc) are connected in series along w/the lamp. The cold resistance of these is lower than when they are hot (after 10 or 15 seconds of warmup) Cold more current passes thru lamp yielding a brighter illumination. As the filament warms the resistance increase and less current passes thru the lamp yielding less brightness. That's the long answer.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
