pyramid ps-46kx power supply

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i bought this power supply new several years ago and shortly after i got it the current meter starting acting up. it for the most part is non responsive, if i tap on it some times it will jump around but will hardly ever start working properly. this has been a pain for years and now i'm getting tired of it. the other day perry asked me how much current a particular amp was drawing and i had to pull out my power supply, take the cover off inspect it and see if i could find a problem. i saw nothing obvious that was wrong but there is something. when i put it back together it worked like new for a few hours and now it is worse than before. when it stopped this time i did nt pull the power supply apart i just tapped it a few times and now the lights for both my meters have stopped working!!! the voltage meter has never given me any problems nor has the actual power supply. i have noticed that if i put a signifigant load on the power supply (30+ amps) the current meter will sometime be responsive. has anybody had this sort of problem before? should i try to replace the current meter?
 
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Disconnect one of the two center terminals completely from the power supply. Set your meter to diode check and touch the probes across the two center terminals (the outer terminals are for illumination). Does the meter swing every time you touch the probes to the terminals? If so, the problem is on the main board or a connection between the main board and the meter. The pots on the meter could be dirty or intermittent but that's less likely. If the meter swings the wrong way, reverse the probes on the terminals.
 
the other day it stopped working again so i was going to try to turn the pot as you instructed but there was so much glue on it i had to remove it and scrape the glue off. i did the best i could but it was still stiff. anyways it wound up breaking when i reinstalled it and tried to turn it to see if it would make a difference. but before i removed it i noticed when i would mess it the current meter would intermediatly respond. i also measured across the pot when i removed it and it was at 300 ohm (10k pot 1/2 way up). but when i resinstalled it the current meter was no longer responsive. so i did the diode check to it again and the needle was still jumping. when the pot was out it appeared to be working (all the way down = 10k ohm, all the way up = 0 ohm).
 
You guys may already have it, but incase not I will post a link to the schematic. This should be the one for yours.

You can actually go to pyramidcaraudio.com then click on power supplies / inverters, & most if not all of the “linear” style power supplies have the schematics in the manual, just scroll down a couple pages & its there. Its on page 3 in the PS-46KX manual. I did not see the schematic mentioned in the thread but I may have missed it. I know these supplies are not too terribly difficult to troubleshoot even without the schematic, but could come in handy.

(Hopefully the link works)

http://www.pyramidcaraudio.com/manuals/PS46KX.pdf
 
thanks everyone it must have been a faulty pot. i replaced it last night and the meter is still working this morning. that hasn't happened in years!! now i can actually see the current draw rather than guess. i checked it with my fluke meter and it appears to be accurate
 
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