Hi,

What is the different between paper capacitor (packed in aluminium
body) and PIO one ? I found some russion paper-caps but don't know how
good is it.

Thanks !

If you want any comments you'll have to tell us what the type is - what
letters/numbers are written on the case?

=== Andy Evans ===
Visit our Website:- http://www.artsandmedia.com
Audio, music and health pages and interesting links.

(ADAM) wrote in message . com...
Hi,

What is the different between paper capacitor (packed in aluminium
body) and PIO one ? I found some russion paper-caps but don't know how
good is it.

Thanks !

I've seen a few different versions of these Russian capacitors:

The types sold as "PIO" are in fact Mylar film/foil types, some have a
trace of mineral oil inside. These are the ones labeled "K40Y9" These
have metal bodies with glass end seals.

The type packed in the aluminum body with rubber end seals are true
paper/foil capacitors, there is no oil inside.

The main difference between the two, other than the difference of
dielectrics used, are leakage factors. I've used the K40Y9 types
without any problems, they have extremely high leakage factors. The
paper types I've also used, and had some problems in high impedance
grid circuits, namely coupling to the output tube grids in fixed bias
designs. The paper caps are terribly leaky, and they can foul up the
bias on your output tubes (they leak + DC from the previous stage).

Personally, I wouldn't use the types sold as "paper capacitors"

Gintaras used to have a nice selection of the K40Y9 capacitors, but
his supply is running low. I bought many 0.1 uF and 0.022 uF
varieties, and am having a hard time locating them now.

The K40Y9 is a superior capacitor, it was very well designed for
military applications, and they make wonderful audio signal
capacitors.

There are a few other Russian made caps that are also good, there is a
Poly type and a Teflon type, and both perform very well.

Best of regards,

Ryan


www.hotglassaudio.com

Sorry,

I mean the K42 type and K75 type. Both I saw in ebay with green body.

Regards !

ohawker (Andy Evans) wrote in message ...
If you want any comments you'll have to tell us what the type is - what
letters/numbers are written on the case?

=== Andy Evans ===
Visit our Website:- http://www.artsandmedia.com
Audio, music and health pages and interesting links.

The K40Y9 is a superior capacitor

Yes, it's nice, but the teflons are better.The green K75s are nothing special
at all, not worth it as a signal cap.

=== Andy Evans ===
Visit our Website:- http://www.artsandmedia.com
Audio, music and health pages and interesting links.

ohawker (Andy Evans) wrote in message ...
The K40Y9 is a superior capacitor

Yes, it's nice, but the teflons are better.The green K75s are nothing special
at all, not worth it as a signal cap.

=== Andy Evans ===
Visit our Website:- http://www.artsandmedia.com
Audio, music and health pages and interesting links.


My main problem with the Teflon caps is the voltage rating, I can't
find any over 200V, and I generally need 400V capacitors. They are
very nice though.

The green K75's work decent, I think they are Mylar. I wish the K40Y9
had an insulated body like the K75's.

The metal case K40Y9 with glass ends comes in more of a variety,
voltage is high enough to allow use in most applications. They are
rather small and easy to work with. Too bad the supply is depleting
for these, they were good cheap capacitors. I'd like to find some 0.1
uF 1000V jobs.

-Ryan