MFD? Same as uf? Cap Question

I'm changing all the caps in an old supro and they're all labeled .02 mfd 400v, etc. Is that essentially the same as the uf label on more recent stuff? There are 6 total varying from .01 to .05 and there's one dry electrolytic labeled 25 mfd 25 vdc. I don't even know what to look for on that. I'd like to use some nice caps in the replecement. Any help will be appreciated. Thanks

You probably only need to replace the electrolytic caps. Replace the 25/25 with a 25/50.

mfd means the same as uf and µf.It is an abbrevation for mikrofarad.

Cool... So will .022 be the same as .02? And will .047 equal .05? Thanks

Cool... So will .022 be the same as .02? And will .047 equal .05? Thanks

For all practical purposes: YES!

Just out of curiosity,do you know the the model name or number of the Supro amp?Limbe

I think its a 1600 or 1600B supreme. It has the field coil speaker which should place it in the late 40's or early 50's. I've been getting some email help along the way and I'm just looking for where to buy caps now.

If you ask an electrical engineer, mF is 'millifarad'. For some reason though, many older caps use MFD (or mfd) to mean 'microfarad'. It's unfortunate. Pretty much all modern electrolytics get it right though, using uF for 'microfarad' (except the 'u' is not a 'u' but a lowercase Greek mu).

If you ask an electrical engineer, mF is 'millifarad'. For some reason though, many older caps use MFD (or mfd) to mean 'microfarad'. It's unfortunate. Pretty much all modern electrolytics get it right though, using uF for 'microfarad' (except the 'u' is not a 'u' but a lowercase Greek mu).

Exactly what I was thinking, although I'm a chemist not an electrical engineer! Just as in measurments of volume, ml means mililiters, and ul means microliters.

If you ask an electrical engineer, mF is 'millifarad'. For some reason though, many older caps use MFD (or mfd) to mean 'microfarad'. It's unfortunate. Pretty much all modern electrolytics get it right though, using uF for 'microfarad' (except the 'u' is not a 'u' but a lowercase Greek mu).

In 30 years I have never referred to any capacitor in "milli" farads. For that matter, I have rarely ever heard caps mentioned as "nano" farads.

A milli farad cap would be huge, considering it is 1000 microfarads!

Most caps are either referred to as microfarads or picofarads.

In 30 years I have never referred to any capacitor in "milli" farads. For that matter, I have rarely ever heard caps mentioned as "nano" farads.

A milli farad cap would be huge, considering it is 1000 microfarads!

Most caps are either referred to as microfarads or picofarads.

It depends on where you are and what you do. The US is rather alone in it's neglect of nano prefix. It is the norm for everyone I corraspond with outside the US.

As for as milli goes, all things are relative. 2-3-4 millifarad caps are pretty common below 25v, and lest not forget the caar audio crazies that use 1 to 2 Farad caps to "stiffen" the supply that bank of 1000w amps trying to blow the windows out.

It depends on where you are and what you do. The US is rather alone in it's neglect of nano prefix. It is the norm for everyone I corraspond with outside the US.


+1 - you won't find a lot of nF caps in amps, but if you're into building effect pedals, you'll find nF values quite often there; also, all the mail order parts suppliers list parts in nF, pF, uF, or whatever is appropriate so the can list whole numbers, and not decimals...

And anyone looking for the proper symbol, use copy and paste! ;)
μF
I google microfarad and copy/paste mu when I need to type it.
If you work with electrical engineers with sloppy handwriting, μ and m can look very similar.

+1 - you won't find a lot of nF caps in amps, but if you're into building effect pedals, you'll find nF values quite often there; also, all the mail order parts suppliers list parts in nF, pF, uF, or whatever is appropriate so the can list whole numbers, and not decimals...

You ever use a 0.022 or a 0.047 in an amp? Yeah, quite frequently. That would be 0.022 μF or 0.047 μF... which is 22 nF and 47 nF, respectively. So they are actually everywhere, it's just that for some silly reason (well, I'm sure someone had a good reason for it at some point) it is convention to reference them relative to μF or pF.

Callaway is quite right.The three prefixes you should memorize are pico,nano and mikro.1000 pF is 1 nF and 1000nF is 1 µF.You won´t find any other values in guitar amplifiers or effect pedals.