Why would you go to all that trouble, if you were restoring something youd get the correct cap or just solder a new cap in the circuit... not go to all the hassle of opening up a cap adding the new one then closing the case again
There are some purists who want to hide new, non-original parts in order that the restored unit should LOOK completely original.
Personally I don't subscribe to that way of thinking. I want any tech who looks at the machine subsequent to my having worked on it, to know EXACTLY what I did, in order to make his life easier.
As far as "you'd get the correct cap" - absolutely not.
You don't dare touch ANY NOS capacitors - original or otherwise, no matter what the snake-oil salesmen tell you.
Generally speaking, any unused cap over 5-7 years old is GARBAGE. Apart from taking a massive chance on the electrolyte having dried out from non-use, you'd need a variac to reform the cap, and even then you're not guaranteed any success.
Buy Electrolytic capacitors from Trusted Suppliers ONLY, and ALWAYS check the date code before committing to buy!
Personally I don't subscribe to that way of thinking. I want any tech who looks at the machine subsequent to my having worked on it, to know EXACTLY what I did, in order to make his life easier.
As far as "you'd get the correct cap" - absolutely not.
You don't dare touch ANY NOS capacitors - original or otherwise, no matter what the snake-oil salesmen tell you.
Generally speaking, any unused cap over 5-7 years old is GARBAGE. Apart from taking a massive chance on the electrolyte having dried out from non-use, you'd need a variac to reform the cap, and even then you're not guaranteed any success.
Buy Electrolytic capacitors from Trusted Suppliers ONLY, and ALWAYS check the date code before committing to buy!
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Don't matter, its like going to all that trouble to put a smaller cap with different voltage, value etc in a larger cap body... its pointless unless you are going to fake some one, you would not do it on working equipment... if you wanted it to keep working.
Maybe I should have put...
But a cap!!!
Maybe I should have put...
But a cap!!!
Hello,
The only caps worth buying so far on ebay for me were the Russian paper in oil and teflon caps.
I have a stock of Black Gate which i did buy in Japan a decade ago. They are original but i will probably not put them on ebay.
If you come across cheap parts they are probably copy and some of the expensive parts might be copy too.
greetings, eduard
The only caps worth buying so far on ebay for me were the Russian paper in oil and teflon caps.
I have a stock of Black Gate which i did buy in Japan a decade ago. They are original but i will probably not put them on ebay.
If you come across cheap parts they are probably copy and some of the expensive parts might be copy too.
greetings, eduard
this would ONLY apply to electrolytic capacitors and probably only when they are more than 20years old and never used.
You don't need a Variac.
One needs a very low current, DC voltage supply and a resistor to limit the reforming current.
It is mainly heat that ages electrolytic capacitors.
Old stored electrolytics can be brought back to virtually "as new" (or New Old Stock (NOS)) by simply reforming to their rated voltage.
Yes, but the presence (or absence) of voltage on the cap also plays a significant role.
As example I link to this datasheet of a BC/Vishay cap widely used in industrial electronics. This cap has a useful life of 5,000 hours at rated voltage and ripple current and 105 C. At 0 V and 105 C, however, this drops to a mere 500 hours.
Useful life at more benign conditions can be as high as 125,000 hours.
I agree that temperature is the biggest factor in capacitor ageing.
However, at 105 C, the presence of a rated voltage already multiplies useful life by 10, hardly negligible IMHO.
I wonder why anyone would want to store caps at 105 C, though.... I'd rather like to see a shelf life specified at 15-25 C...
However, at 105 C, the presence of a rated voltage already multiplies useful life by 10, hardly negligible IMHO.
I wonder why anyone would want to store caps at 105 C, though.... I'd rather like to see a shelf life specified at 15-25 C...
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