OK for physical size difference of orig and new e-caps to be this big?

62vauxhall

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#1
Got this 1960's tube receiver and am replacing capacitors. I am aware that new capacitors will be physically smaller than old ones but this differential is, in my opinion, very big indeed.

Is there cause for concern or should I be be looking for different, bigger replacements?

FWIW, the Nichicon is bi-polar 50V 2uF and the small blue one is an Elna bi-polar 50V 2.2uF.

The original gray Elna 50V 20uF is rated for 75 Surge Volts but I haven't found/seen such a spec for the Rubycon 50V 22uF that I got to replace it.

IMG_4048.JPG IMG_4049.JPG
 

8991XJ

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#4
Well if you get the cheaper radial caps they are that small. I would expect the radial caps to be smaller, too but maybe not that small. If the voltage is the same or higher and the capacitance is the same they will work just as well as the design needs, better than the originals, caps are getting better. and apparently smaller
 

Gepetto

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#7
Progress has been made with materials, that is for sure and caps have gotten smaller. When you see a size difference that is too good to be true, it likely is. Cut corners usually at the root of it. At the end of the day, physics is physics.
 

mlucitt

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#8
I think we should stick with the Nichicon Muse (Fine Gold are good too) capacitors to be consistent, Mouser has the full line. They are also very good caps. You will never have to worry about Chinese copies, or inferior grade internals leading to non-specification performance issues.
 

8991XJ

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#10
I'm getting some tubes from Jim McShane and I ran my question past him . He pretty much said the same thing.
Most excellent, I have learned enough to type one sentence that is pretty much the same thing one of the respected voices would say.
Those large caps dissipate heat better, the smaller ones may burn out quickly.
If the voltage is the same or higher it shouldn't overheat, but if there is a concern you can up the voltage and get a more comfortable feeling.
 

Gepetto

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#12
3 parameters are critical for caps (besides the nominal ratings), ripple current capability, operating temperature and voltage rating/margin.

Ripple current is the biggest self-heating component in electrolytic caps when you are operating under the rated voltage level.

These 3 elements are usually behind the swelling of caps or venting of caps.
 

62vauxhall

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#13
I thought I'd have this job wrapped up by now but I misread the value of one capacitor. I made what I thought would be my last trek to the parts store this morning but I guess I'm going again tomorrow. So install that one and 13 more and I will have gone as far as I can for the time being.

Also picked up the tubes today so 160 km driving (pretty much bang on 100 mi) and I felt like running no more errands.

Maybe get everything in by Saturday - see if that little capacitor goes POW!!
 
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