Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

37-630T Volume Control
#1

The schematic shows this radio using a 2 megohm volume control with a 1 meg center tap. I measure the resistance between the two outer lugs and I see 3 megohms on my meter. When I measure between the center and an outer lug I see 1.5 megohms and it goees down to .7 meg with the control all the way clockwise (full volume) position.
is this poteniometer ok ?  While cleaning the track I noticed one spot that appears rough while the remainder is smooth.
#2

With the shaft facing towards you and the 3 closest terminals pointing downward. Connect your ohm meter to the two terminals to the left. With the shaft turned all the way ccw you should read pretty close to 0 ohms (shorted). This is typically were most of the wear happens and is the failing point. Turn the shaft cw so it is in the half way position and you should read about 10% of the total resistance in your case 300K. With the shaft turned full cw should read the full resistance of 3M. Best to use an analog meter as worn spots with cause the needle to jump around.

GL

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
#3

With the shaft all the way ccw I don't get zero ohms, I'm reading 99 ohms. All the way cw I get 3.1M. On the analog meter the needle moves smoothly. Should I replace this control ?
#4

You almost never get 0 ohm. 99 ohm is very good.

As for 3M i/o 2M, I'd test it befor getting it condemned: it is likely to work.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.




Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
Hickok AC51 tube tester
Absolutely no one is going to reverse engineer that circuit. Even the iron core is missing.RodB — 10:37 AM
IF can wire size and Rubber mounts?
Thanks to both members for your help regarding wire and tuner mtg supports. regards--Johngeorgetownjohn — 09:33 AM
Hickok AC51 tube tester
Note that no power cord, power switch, or power transformer switch are shown. That (along with my experience with full s...DaleHCook — 07:09 AM
IF can wire size and Rubber mounts?
A pair of wire strippers can give you an idea of what the existing gauge of the wire leads are in the IF can, I think it...Arran — 06:07 AM
My last cabinet for this year
Hello Dan, That is really beautiful what great looking radio you have ! I have friends who live in Calgary and the wea...radiorich — 01:51 AM
Philco Predicta Siesta picture over time getting dimmer
I found that the wire insulation was burnt.  The fly back needs corona dope! Why would someone put that there?Platinumblonde36 — 01:09 AM
Philco Predicta Siesta picture over time getting dimmer
This is what it looked like beforePlatinumblonde36 — 01:01 AM
Philco Predicta Siesta picture over time getting dimmer
Platinumblonde36 — 12:58 AM
Philco Predicta Siesta picture over time getting dimmer
Platinumblonde36 — 12:57 AM
Philco Predicta Siesta picture over time getting dimmer
I'm finding some strange things in my set and for the most part it's also original, so I need to start going over everyt...Platinumblonde36 — 12:55 AM

[-]
Who's Online
There are currently no members online.

>