Russian Cap Info

[jelle]

Actually, Mark cross posted this info. This list is a compilation of the Russian cap info that I found online on several audio forums. I posted it as a reaction to an ad that claimed that the green k42Y caps are PIO's while they are not, according to my info.

I enjoyed the Bumblebee link, Outtahear, thanks!

Did you notice that the value of these caps goes up by about 30% due to evaporation of those PCBs? Also the caps start leaking DC so the filtercharacteristics of the tone knob will be (noticable?...I do not know) different from the glass seales russian caps which are techically not leaking DC.

Jelle

[collinsamps]

Well said Andy

The term snake OIL salesman actually fits this time around.

[outtahear]

Did you notice that the value of these caps goes up by about 30% due to evaporation of those PCBs? Also the caps start leaking DC so the filtercharacteristics of the tone knob will be (noticable?...I do not know) different from the glass seales russian caps which are techically not leaking DC.

Jelle

Possibly from being such a negligibly small voltage, but haven't noticed any scratchiness with 'bees, but I have in some extremely leaky Sangamo films (N.O.S., no less.)

Could explain why some people who purchased these (Russians) prefer 'em to their original bumble bees.(?)

Must be the (snake) oil............(Ukranian)

[briane]

Nice....First flame war Ive seen in over a long time....

Its the absence of putting others down for differing beliefs that does make this a great place.

(excerpt removed)...

All from someone seeking to educate others.

[Andy Le Blanc]

Got to say that that recreation of that fight scene from , what was it?,
"They Live", was one of the best episodes of Southpark ever made.

Maybe a Sarah Palin image would have been better?!!!

[outtahear]

Got to say that that recreation of that fight scene from , what was it?,
"They Live", was one of the best episodes of Southpark ever made.

I think it was frame for frame

[collinsamps]

What fight? Opinions are opinions.

[jelle]

Did you notice that the value of these caps goes up by about 30% due to evaporation of those PCBs? Also the caps start leaking DC so the filtercharacteristics of the tone knob will be (noticable?...I do not know) different from the glass seales russian caps which are techically not leaking DC.

Jelle

Possibly from being such a negligibly small voltage, but haven't noticed any scratchiness with 'bees, but I have in some extremely leaky Sangamo films (N.O.S., no less.)

Sorry, I wasn't clear...since there is no DC on the cap it could not leak DC or become scratchy for this reason in a guitar.

I was trying to say that the DC decoupling capability of these old bumblebee caps goes bad as they get old, they start to become conductive for DC. So effectively we have a capacitor that is bypassed with a resistor. Does anyone know what kind of DC resistance (ohms) we are talking about? And what threshold voltage is needed to make the caps show their leaky characteristics? Reason I'm asking is that this will lower the impedance of the tone ckt in the guitar for the lower frequencies (or put another way: increase the load on the lower frequencies as well).

In addition, the value of the cap increases as they age which also increases the load on the mid/lower frequencies like selecting a bigger cap would.

Is there anyone with a couple of bumblebees and some test equipment who wants to test this and post the results?

jelle

[outtahear]

Jelle-

I seem to remember , more often the value drop (i.e., .022s reading .018) ,and ESR being quite good, (Again, from memory, and in guitars..)

Values tend to be +or-%20.

Not all "Bumblebees" are equal, (or even "bumblebees")
tends to be used as a catch all for any molded cap w/"goo" inside.
(General instruments, C.D.,...)

Again, I'm out of the shop 'till May 7th, so...