Capacitor p0rn

[Grainger49]

I thought if you used a cap as an interstage cap you had the outer wraps toward the driver stage.  I know the outer foil goes to the ground in the power supply and toward the output terminals at the output tube.

looks like the only indication is the direction of the writing.

[Bonzo]

There is a small symbol on the left, it looks like a "C", that is the indicator of outher and inner foil.

I also red on the net that the symbol is wrong sometimes 

Ciao!

[JamieMcC]

I soldered the Russian Teflon K72P6 into the Crack this morning, it is 0.056uf in value. The smaller black capacitor which it is cable tied to is a JFX 2.2uf metalized film

The first impression is phew a big relief nothing sounds any worse! 

Initial impressions with the Teflon in the chain are encouraging.

I have read it can take a while for the Teflon caps to settle down?

(https://www.head-fi.org/content/type/61/id/1036083/width/350/height/700/flags/LL)

(https://www.head-fi.org/content/type/61/id/1036082/width/350/height/700/flags/LL)

(https://www.head-fi.org/content/type/61/id/1036094/width/350/height/700/flags/LL)

[mcandmar]

Teflons can take forever to settle down, on Grainers advice i had mine connected to an amp to burn in so they had ~50hours on them.  Once installed they still didnt sound right for another week of solid use so the recommend 100-150hours is about right in my experience.

Having said that it may differ when used in power supplys vs the audio chain.

[Paul Birkeland]

I use Russian otput caps also on my quickie with good results (k75 PIO bypassed with k72 teflon).
I found this pic on the net that shows how to connect russian caps, hope it helps.

Ciao!

FYI - the inner/outer foils on those caps are not consistent with respect to the lettering.  (As the image you posted would suggest)

[Bonzo]

Ciao Paul,
I spotted this image on a thread on diyaudio about russian caps and on other russian sites.
The symbol that indicate inner and outher foil is printed near wattage and tolerance info.
I don't know if it's always right, as I also spotted a post where some caps were opened proving that the symbol was uncorrect (but it was only one post against lots of sites).

Thank you for your info, is always difficult to know who's right on the net.

Ciao!

[JamieMcC]

interesting info on the inner outer foil C symbol. thanks I did not know this. Looking again on the capacitor the symbol does now make some sense.

(https://forum.bottlehead.com/proxy.php?request=http%3A%2F%2Fcdn.head-fi.org%2F3%2F34%2F900x900px-LL-34681b3c_007.jpeg&hash=69e8b0468f41951890760ef254071f3275dfb572)

[Grainger49]

Ok, first let's say that having the outer foil in the right orientation can give additional noise rejection.  It doesn't affect the sonic characteristics. 

Then I have to note that all the KKs (Kommie Kaps) have metal shields outside the cap itself.  That rejects noise.

But maybe we can measure the cap and find the outer foil like measuring the outer wraps on a coil.  PJ told me to measure capacitance from one lead to the outer plastic wrap of a choke, then the other lead.  The lowest capacitance is the outer winding.

I always like the pragmatic answer.

[mcandmar]

I found this recently re testing caps to find the inner/outer foil.  Haven't tried it myself but it seems plausible..

http://jimmyauw.com/2010/04/24/observing-inner-and-outer-foil-of-some-popular-capacitors/

[JamieMcC]

I found this recently re testing caps to find the inner/outer foil.  Haven't tried it myself but it seems plausible..

http://jimmyauw.com/2010/04/24/observing-inner-and-outer-foil-of-some-popular-capacitors/

Yep have seen that also seem to recall seeing something similar on youtube.

I wondered what the pros here thought of the pocket or pc (laptop) based scopes?

[mSummers]

Is there a way to find which is the outer wrap on a non metallic cap like the Mundorf M Cap without having to buy an oscilloscope?

[mcandmar]

Ciao Paul,
I spotted this image on a thread on diyaudio about russian caps and on other russian sites.
The symbol that indicate inner and outher foil is printed near wattage and tolerance info.
I don't know if it's always right, as I also spotted a post where some caps were opened proving that the symbol was uncorrect (but it was only one post against lots of sites).

Think i found a flaw in that theory..  i chose the top as the in side, cant remember why i came to that conclusion.

[Bonzo]

Think i found a flaw in that theory..  i chose the top as the in side, cant remember why i came to that conclusion.

Wow! never seen such a big ft3!
Well, it seems the inner foil is market with a diamond. Can you please check if the diamond-like symbol is printed on one side of the cap?

Ciao!

[mcandmar]

Wow! never seen such a big ft3!
Well, it seems the inner foil is market with a diamond. Can you please check if the diamond-like symbol is printed on one side of the cap?

Ciao!

They are the .1uf variety, i believe those and the uber rare .22uf versions are the largest of the FT teflons.  Both are dwarfed by the 4.7uf K75 PIO Green giants, those are 4-5" long.

I dont see any markings anywhere else on them other than the section shown.

[Grainger49]

I, very recently, saw a 0.47uF for sale.  I don't remember the voltage rating.