I bought this Exposure 6 power supply at a yard sale a couple of years ago for $20. It was built in the mid 1980's and the fellow I bought it from said he had measured high ESR on the capacitors which he thought were dried out. The caps. are 10,000uf, 63volt and are screw terminal type and quite large. I have a few new Cornell Dubilier 10Kuf, 63 volt through hole caps. that are tiny compared to the originals and I am wondering if there is any downside to using them as replacements?
Thanks for any info.
Thanks for any info.
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Small caps will not have the same or sufficient ripple current rating required for power supply smoothing service. They will over heat, swell and spread goo where it shouldn't go. Do your research of the existing caps properly and buy replacements with appropriate ratings.
I would test the leakage before doing anything. The best way to do this is to charge the caps in place but with all the loads removed and measure how long long they take to self discharge. If they stay charged for a day or more then I would keep them.
I would test the leakage before doing anything. The best way to do this is to charge the caps in place but with all the loads removed and measure how long long they take to self discharge. If they stay charged for a day or more then I would keep them.
Thanks for the replies. I turned the PS on for the first time since I bought it and it reads dead on at 24 volts which is the rated output so I am going to use it to power my Korg B1.
BTW, am I correct in thinking that even though this PS has more current than the SMPS speced for the Korg B1 the B1 will only draw the current it requires? Or will I blow the B1 with this PS?
BTW, am I correct in thinking that even though this PS has more current than the SMPS speced for the Korg B1 the B1 will only draw the current it requires? Or will I blow the B1 with this PS?
The amplifier only takes the current it needs.
You could have a million amp supply but if the amp only needs 1 amp thats all it will take.
You could have a million amp supply but if the amp only needs 1 amp thats all it will take.
Those caps are, in my opinion, ridiculously larger than the transformer or the rectifier. Unless this is a very odd application, they do not have to be this big.
FWIW: ripple current heat is a thing for industrial and switcher supplies working at high ripple. For linear audio we need a large cap for low ripple. Typically (perhaps because cap makers know what we are doing) the working ripple current comes to a large but quite safe fraction of the current rating in domestic use.
FWIW: ripple current heat is a thing for industrial and switcher supplies working at high ripple. For linear audio we need a large cap for low ripple. Typically (perhaps because cap makers know what we are doing) the working ripple current comes to a large but quite safe fraction of the current rating in domestic use.