Thread
:
This has me puzzled (resistor change)
View Single Post
#
11
Posted to sci.electronics.repair
Look165
external usenet poster
Posts: 157
This has me puzzled (resistor change)
Carbon resistors are noisy.
We used that for making white noise and then by filtering, make sine
wave or else.
With metal resistors there is not enough noise.
a écrit le 20/01/2019 Ã* 23:33Â*:
There is a video on youtube, where a guy re-caps and repairs and tests
out a late 1940's Precision Apparatus E-200 signal generator.
Video name:
"Repair of a late-'40's Precision E-200-C RF signal generator"
This sig gen has a built in audio tone modulator (oscillator). He
replaced a resistor in that circuit, which was out of tolerance. He
replaced it with a modern film type resistor. The audio modulation did
not work afterwards. After testing everything, he went and replaced that
resistor (again) with an old style carbon resisstor, and after that, the
modulation worked.
What the heck?????
I was always under the impression that film resistors are identical
(electrically), and their only difference is appearance. Now I learn
that is not true.....
WHY?????
Reply With Quote
Look165
View Public Profile
Find all posts by Look165