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Registered Member #3766
Joined: Sun Mar 20 2011, 05:39AM
Location:
Posts: 624
Got it from my chem teacher... kinda he said it didn't work and that he wouldn't notice if it went missing, good enough for me
I have a hunch that it's the capacitor, those old cardboard ones didn't last. 2000uF, 25V, and the lytic i'm replacing it with is like 1 twentieth the size.
Registered Member #3781
Joined: Sat Mar 26 2011, 02:25AM
Location:
Posts: 701
nice! there are 3 of these in my physics class my teacher said i'm welcome to use anytime :) Diagnose it first, will it even turn on when you plug it in? most of the time there is a loose connection in the power cord and it just needs to be replaced to fix the problem
Registered Member #3766
Joined: Sun Mar 20 2011, 05:39AM
Location:
Posts: 624
Well, the ones we did have that work had voltages and currents swinging wildly, so I'm guessing the caps are the problem, since everything else is pretty much rock-solid. And replacing the cap isn't going to hurt anything. Those paper ones are terrible.
It doesn't actually even have a plug, so Ima put one on as soon as I get the new caps in, I know my chem teacher would have replaced the plug if that was it's only issue.
Registered Member #89
Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145
Looks like it has a selenium rectifier in there. Those tend to die simply of old age, and till this day most of those that still exist are dead anyway, and are really worth replacing with a silicon diode bridge. If they fry in operation they also tend to emit toxic fumes.
Registered Member #3610
Joined: Thu Jan 13 2011, 03:29AM
Location: Seattle, WA
Posts: 506
We had some of those in my highschool physics class.
I second that on the rectifier. They look like a stack of square metal plates with a terminal on each end. They fail regularly, and pump out copious amounts of some of the most foul smelling brightly colored smoke you will ever encounter. Replace it with a modern silicon diode that that may well fix that thing right up.
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Check out my new PSU! (fixed variac)
