An interesting capacitor question

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I bought these russian mil caps off ebay.

They were listed as being polystyrene, 250V, 0.47uf. The values are fine, well in spec. no problemo.

I took one apart, after I had bought 75 of them off the guy. I felt it was film, and I was done. The film felt 'metal like' and there was a nice polystyrene feeling thin layer on either side. Good enough I said,and emailed him back,asking for more, if he could find them.

He found more. About 400 more, in total. 0.5uf (141) 0.399uf (200) and 0.3uf (100). I set it up to buy the rest. All rated at 250V (apparently, who knows what 250B means in russian)

I decided I wanted to use them to so some bypass in my phono section, in my preamp. I checked,and one side is biased at 180-190V, for the signal passing caps.

So, I found my dismembered cap I killed for my little 'truth' test, and proceeded to take it apart in a more detailed way. I wanted to see if a thicker film was in evidence, and the cap might be applicable in a circuit where Mr. Moore decided that 600v caps were needed. Mil spec is like that, and can be far under rated compared to a commercial rating system. I get the feeling that these caps can take repeated and constant abuse at something like 500V, not 250. Just a feeling. Or that the '250B' means 250VAC, not DC.

What I found was a film that was metallized on BOTH sides, and to a very high level of metalization. In comparison, you can use a solen cap film to make dark sunglasses,and the coating ona solen is on one side only. This stuff, you can't see through at all, but the impedance on one given side is about the same as the solen, across a given distance on the metalized side. What I mean is, if you take a bit of the metallized from the solen cap, measure the resistance across a given length. Lets say you get 3.5ohms. Take the film from the USSR mil cap,and get about the same, maybe a touch less. 10%-20% less. Then, the russian one is conductive on both sides. so cut that number in half again. The metalization is also very solid, or thick. On either side.

The separator film is on either side of the metal film on the russian cap and it is also a separate piece. so in triplicate, and far thicker feeling than on the solen, as well. It also does not feel like polyproplyne, it feels like polystyrene. I guess I'd better take apart a mylar cap and compare the film 'feel', maybe....

So it's a double metallized thick coated film, with polystyrene separators.

It's a metallized film polystyrene cap!!!It 'sounds' like a metal film cap, to a very large extent and has the advandatge of being polystyrene, as well. This is weird. :cannotbe:

I had done some preliminary listening tests by putting it in some different places, and in each instance there was a notable increase in fidelity, so I didn't bother to investigate further and thought of it as a proper metal film polystyrene cap. But it isn't.

But it IS very, very, good! Better than any metallized cap I've ever used, and I've just about had my fill of all metallized caps, period.

The packaging also says 'polystyrne' according to the USSR designation system. The price I'm paying, which is very low, means that it is terrifically unlikely someone made new labels just for me.


I'm a bit confused in this one, this cap is a new one on me.

Anyone have experience with such a beast?

I gave Anatech (Chris) 8 of tehm to play with, when I was at his place last week. What I need to do, is to get him to run the Diss fator test again, (Hello Chris!) at 100khz, and check these puppies. Then compare that to a real polyprop film cap and to a polystyrne film cap. Then maybe I can get a least some understanding of what the heck is going on insofar as the numbers go.
 
Hi,
is this Russian cap of folded construction or rolled?
Are there multiple lead outs commoned to the output pair?

But, back to the capacitance.
The double metalised film will form a capacitor in it's own right.
The adjacent layers whether folded or rolled will have dual separators between the metallised layers.
I would guess that the double separator layers will be thicker than the single metallised film.

Now, here is the difference between rolled and folded.

In rolled the common metallised layers are alternate with the two different metallised layers forming capacitors first across the dual separator AND secondly across the film. If the dual separator is thick then the metallised film will dominate the capacitance. Why double the separators, it appears to reduce capacitance for little benefit.

In folded construction the common metal layers are adjacent and then the next pair of metal layers are common.

The capacitance, in this case is only across the metallised film. There is no additional capacitance across the dual separator since the metal layers are common. In the folded case you do not need any separators.

If my imaginations are correct then folded constructionachieves no extra capacitance and due to redundant separators is far bulkier than needed in return for reduced inductance.
The rolled construction reduces the effectiveness by dualling the separators, when one would be sufficient.

There is another senario. Maybe the separators are extremely thin and of a high dielectric constant and low insulation value. Forcing dual separators to achieve the voltage rating. Then the separators start to have a beneficial influence. But polystyrene does not have a high dielectric constant, so that does not seem feasible.
A conundrum. I am no further forward and I suspect my post does not help you either.
 
SY said:
Is there continuity from one side of the film to the other?


After a bit more investigation, it appears there is only the one separator film, it being apparently, polystyrene. The metallized film is definitely identially conductive (relatively speaking, simple tests) on either side, but not through to the other side.

So, conductive on both sides, likely a polyproplyne film, and then the styrene separator. Each cap is made up of two of these windings per capacitor. So, internally doubled up on the highly metallized film (parallel paths) and then two of these in parallel in each actual 'capacitor' body. For example, the 0.5uf caps I'm getting from this guy, will have two 0.25uf caps in the case, parallel stacked. They are approx twice as long as their diameter, each round roll, that is.

I also noted that the oxide layer from the Solen caps can easily be removed via rubbing. The russian cap? This stuff is so well attached or layered that this is VERY difficult to do. Sometimes the metallized layer comes partially off in a clean layer, onto the styrene separator layer. So it is quite well constructed and has a definite depth (the metal layer).

All in all, a very nice cap, but not exactly what I was led to believe I was getting. Polystyrene is always film/foil, to my recollection, this is an exception to that rule. To be fair, the guy selling them to me has no idea either, I'm sure, and I'm not about to alert him to possibilities.

When I get this batch in, I'll send a few off to you guys (only a few guys!) to garner an opinion. I'm pretty darned firm (a relatively educated opinion) about them being quality in terms of sonics and a general improvement overall, and roughly comparable to a true metal cap, but I'm not stupid enough to rely on my opinion alone.

At worst, I expect that folks will find they compare to the best that metallized film has to offer- but just a clearly noticable hair better. I just put them as bypass on a 12.22uf cap bundle in the main signal pass point in my MFA phono section. That bundle is a 3 piece affair, at 2x 6.0uf Rel-cap PPMT, and a .22uf RT rel-cap. There was a definite change (duh!), with the 0.477uf Russian cap put in there, but I'll have to let it sit for a few days to really get an idea of where things stand. More complimentary than destructive, so It seems to agree fairly well with the Rel-cap Styrene/tin foil cap that is in there (the 'RT' designation Rel-cap)

I/we will hopefully be isuing speakers soon, and I'll likely keep most to do bypass work on differing sections of the first issuance of any given model's passive crossover. This can save us a ton of cash, comparatively speaking, at the same time the speaker can be quite sweeteend and cleared up, compared to equivalent $$$ competition. These units seem to be designed for high frequency and high peak current.
 
Well..... tomorrow I get my pricing on 5N copper and silver foils, and teflon films..and then the fun begins. Time to experiment!

I plan to design and execute a new type of inductor, a new type of capacitor, and a new type of wire. All three having a design and geometry that has not been seen yet. See what happens when you start playing with this stuff? :p

(truthfully, I've been sitting on these designs for over a decade. Time to get'er'done)
 
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Capacitor test numbers

All right then.

At 10 KHz the readings very fairly stable. All capacitors measured a dissipation of 0.0004 or 0.0005. I had two caps that measured 0.0016 and 0.0009 respectively. I didn't bother working out the total uncertainty. It is plain to see these are rather good figures.

At 100 KHz the readings were unstable. Watching the changing numbers, dissipation seemed to run 0.0022 to 0.0033. Our previously misbehaving caps measuring in the area of 0.0075 and 0.0140. Still, the group measures well.

For comparison I tested some Polyestor 630 V capacitors at the same value. At 10 KHz they ran 0.0093 and 0.0169 at 100 KHz.

Ken, your 0.1 uF caps measured 0.0000 at 10 KHz and 0.0006 ish at 100 KHz. Not too shabby (next to bloody perfect).

The test leads (HP 16089B, Kelvin Clips) were zeroed just prior to each frequency test sequence. The meter used was an HP 4263A (LCR Meter). The 100 KHz test frequency is on the top edge of the frequency range for the test lead set.

-Chris
 
Ok. thanks for the figures and tests!

The caps tested were 8 of the 0.47uf russian caps I gave Chris when I last visited. (the green ones)

The ones that are vanishing low in DF, are a set of 4 of the russian Teflon 0.1uf/200V caps, with their metal cans removed, a new 'wrap' skin, and epoxyed end caps. They look 'just like' a professionally made cap. (the white ones)

In the photo, are the green ones I speak of that are metallized on both sides of the foil, with a polystyrene seperator. You can see what I mean about the construction. Poor Russian man's MIT multicap. Apparently it works, which it would be nice if the multicap did the same. The others, the white labeled ones, are the skinned and epoxyed russian teflon caps. They are easy to make!

The writing is on the next to last layer of the film (wrap) cover, so it won't come off. As you can see, a full pot of coffee was consumed before attempting to write on them.


An externally hosted image should be here but it was not working when we last tested it.
 
PS, the guy whom I am getting pricing on copper foil from. He just happens to be the exact and ONLY (my impression, not his words) US manufacturer of this thin a high purity copper foil, period. I run into the exact guy I need to run into. I can buy any size roll I want. any width and down to uh..a very thin foil. 0.0007" thin, to be exact. What is the real point of mentioning it? about 5 different grades, and I won't ber 'two stepped' in the pricing, as this is the actual manufacturer, which is the hardest place to get to.

Press a supplier hard, and you'll find out very quickly that your pricing isn't what it could be, especially on such rarely used and rarely manufactured items. This is because you can't seem to track down the actual manufucaturer, you get an extra pricing level(distributor pricing) , which cuts deeply into your ability to sell at a profit, as your pricing structure is being affected right at the bottom.

10lb roll, about $300, he said. More then enough to roll me a few, for test porpoises. Re-packaging those russian teflon caps made me hungry for mo'better caps, but throw some labour in, and I can do it on the cheap. Not $100-300-600 for one single capacitor, but with labour, maybe $20 each, maybe less. Now we're talkin.

Now to source the teflon film. Copper/teflon caps, yummy.
 
serengetiplains said:
Ken, are the teflon capacitors an extended foil design?


Most definitely. You can see the 'step' of the foil vs. film ends in the photo.

I have not yet finished paying the man, and can add some more on to my order. Of course, it won't cut shipping expense by more than a few $. He's got lots of them, as most of those guys in the Ukraine, belgium, etc..seem to have. The teflon seems to be far easier to find than the polystyrene. I just managed to find some 10uf versions of the styrene caps, I'll see what they are like.
 
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Hi Ken,
If you want, post me anything you want tested. It's easier than the long drive out here.

The copper foil may be interesting. Other values to consider would be 5pF, 10 pF, 20 pF, 47 pF, 82 pF, 100 pF, 150 pF, 220 pF and 330 pF. I'm thinking of your compensation caps in some amps. I am sure this would make a positive difference. They take more labour than material.

-Chris
 
serengetiplains said:
Ken, would you be willing to purchase some 0.1 teflons for me? 20 would be great. I'm good for it, or can front you money. Or perhaps you could point me to the seller? Would appreciate it.

I'm also interested in new capacitor designs, as you know from this thread. Perhaps we can collaborate.

Tom


The gentleman from the company that makes the copper foil is searching out a suitable silver foil. The copper foil, I recieved the pricing today, it's a 4 day delivery, via pro froma invoicing, etc, at an example pricing of a 3" wide foil, 0.0007" thickness, 10lb roll. At $260, plus delivery costs. That's about 1250 ft on a 3" roll. the 0.001" roll is cheaper, obviously, as less mill work needs to be done to get to 0.001". A less wide roll is likely to not cost much less,as handling and cutting down/off their main rolls is the big deal here. Too bad I can't use 3", it was a number I pullled out of my butt when I asked him for an estimate on the overall pricing.

For optimum cap work, what is the width that works? Small would be nice, for the pf sizes, but the roll would cost nearly the same. cutting it yourself off a wider roll is doable, but it sure would be lots of work! I can easily estimate a good width, but getting a bit of input is always wise. Geometry counts (my best guess-and it is educated-in the school of logical thought, not university), but not as much as people think, if you do the rest correctly. What I mean, is resonant cavity/reflection modes won't count, not the way I intend to build them. They simply won't be there. I also have a expert in dielectric design in the building. At one time in his life, he designed and did lab test/design work for the enamel coatings on magnet wire. All in all, a good coincidence and confluence of skills.

Serengeti, I'll grab 20 more of the 0.1uf/200V russian caps. What end of this big country are you on, anyway? I'm in South East Ontario. Canada's Original Capital. Yes, I know you have that big bottle of spearinol. Paper in oil would be nice,and I have been working on or mentally toying with a replacement of the black gate graphite based fluid/impregnation thing. Black gate is now open to complete supplantation, since the manufacture of such is ceasing. In that particular situation, I'm not ashamed to build from that point, nor am I shying away from taking that technology and taking it a step beyond.

We grind our own pigments, right at the factory and I have access to any additive that it is humanly possible to think of or create, and the capacity (hah!) to properly mix or create ANYTHING. For example, a mix of specific graphite particles, mixed in with,well..I almost blurted it. secret stuff!!! :p.

The science of successfully wetting out additives and dispersing them is not as simple as one thinks, it is a difficult prospect on the best of days. At the factory, they have done things that the industry in general thinks is simply impossible, and done it repeatedly in multiple ways, for over a decade, and designed 6000 complex coatings mixtures. Many times, a given mix does not work, and finding out what happened or is happening can sometimes be difficult. It's a long story, but seperating/'wetting out' a particle mixture properly for good 'sound' in a given capacitor is a big deal, and few can do it right. We excel at that particular task, due to the coatings mixtures. Better than anyone else.

So a PIO copper cap might be the first order of business, with a 'value added' :p spearinol 'impregnated' paper. As for publicly speaking on the subject, what I've said is like a sexy preview that makes you want to watch the film, but it hasn't even been scripted yet! And it's all secret stuff, from here on in. Why? When you stumble onto a good line of thought, you have to assess it's viability as a business enterprise, FIRST. Ie, don't spout seeming gibberish on a fourm, and then try to back track, because it leads to a gold mine. Not greed, just common sense. Look at it sensibly at first. I hope to come up with some basic capacitor designs that everyone can fool with, but as you can see, I'm already headed solidly toward the top of the market, and into an area where the average DIY'er will be hard pressed to follow. Then there is the stuff I'm not even remotely hinting at!

Spilling my guts may make DIY'ers feel good, while reading the daily capacitor DIY soaps - but maybe two or three might bother to make such caps, and the 'potential' (hah!) competition would simply pick it up, and steal my thunder, which is only good business sense. I lost quite a few good ideas (two screen products, for example, were produced by a competitor) on the AVS Forum that way, trying to appease the guys who thought I was an egotistical a$$hole for not speaking publicly on my design ideas.

Not again.

Oh yes, I called Solen today, to ask about the DF numbers on all their capacitors. I wanted to know the measurement conditions. All done at the industry standard of 1khz, at 25 deg. C.

But I have an even bigger problem than all this, actually. I have a special order in my fridge. A case of Kenyan 'Tusker' brand beer, one of THE best beers in the world. I'm trying not to drink, and the damn things are ice cold..and right there. mmmmmm ..beeer....
 
weeelll... since you're looking to be a future gouger of us I'm far less inclined to contribute, deep down we all have that same dream though I guess.

Aside from foil thickness, have you at all considered roughness.

Oh, the last I heard led me to believe black gate wasnt' going anywhere. You speak as though you've insider knowledge as to how they're constructed?
 
We grind our own pigments, right at the factory and I have access to any additive that it is humanly possible to think of or create, and the capacity (hah!) to properly mix or create ANYTHING. For example, a mix of specific graphite particles, mixed in with,well..I almost blurted it. secret stuff!!! .

Eh. Graphite is not the best solution. Use stearate-coated silver balls and flakes (2 or 3 to 1), mixed into a well-blended and milled solution of Saran F310 in BCA. Alternatively, if you want to bake it, there are about a zillion epoxy binders that will work well.
 
Dy:
The graphite was just an intial thought. i'm thinking (now that you mention it) that the epoxy is part of the solution that must be addressed. It's an issue in nonlinearity, on the surface. Hah, get it? Haw.

Classed:
I never said I didn't want to contribute to/with the forum on this. No, not at all. I will simply have to limit what I blurt. Simple common sense. Those who contribute, if I/we get to a 'interesting place', via other modes of communication (email, phone calls and the like) would surely get funky capacitors to play with. But when it comes to business matters, common sense says keep your trap shut. I simply have the bad taste to bring up the subject, as I like everything to be honest and on the table. As for funky capacitors, there would likely be legal forms to sign, if it ever gets that far. Hey, one can dream.

Also, it itakes time to adjust to this particular aspect of real and actual understandings, as our ideas are our children: The idea is nearly worthless, if it doesn't go anywhere. For example, my ideas for coatings at Goo Systems were good and the point at which the company was actually gestated-they were crutial. Beyond that point, they are virtually worthless, and the vast bulk is simply --hard work. What I'm trying to say, is that mental contribution may induce spark, but is not in any way shape or form, the actual fire itself. meaning what? Don't think that your ideas spouted in this particular area are the words of the idealistic capacitor god itself. The may go somewhere, yes, but only if you pursue them yourself, and put your guts and blood into it, does it actually mean anything. Difficult to understand and mentally 'accept', until you've done it at least once.

How do you think Goo Systems started? I wanted enough money to be able to get into and loose money in the audio business. So I set out to commit the crime of brigandage on the video industry, with a new idea and superior product.

The money paid for product is not the issue in this world. Those numbers are actually, most of the time, quite fair. The problem is -and the turning point came- when the Bank of England was created. That was the beginning of the end. Look it up some time. Before that, charging interest was punished by death. execution. Beheading. Burnings. Drawn and Quartered. Those folks knew for a fact how nasty 'interest' actually is, and insidiously wrong it is. For example, the US Fed is a private enterprise, a conglomorate of 11-13 banks, has never been audited or looked at, and creates money out of thin air, with debt pre-attached to each dollar. This means getting out of the hole, is literaly-impossible. The US Fed should be abolished, like yestereday, with extreme predjudice. As for what is going on in this world, in the background right now..as the base reason for everything ugly, right now..do a google search on "Leo Wanta". Don't give up, keep reading. You will be horrified.

~~~~~
I've always lived poor, because I finish an idea, and never bother to follow through. I'd rather think of other cool and new things. I even lived on welfare for 7 years, doing exactly that. Thinking. I told the welfare worker I was 'between idealogical states', and when I stopped musing I would go forward with one of them..and they'd get all their welfare money back, and far more, in the taxes I'd be paying. My tax bill this past year proved that statement abundantly. ouch.

Goo Systems is the first time I actually followed through with an idea.
 
As for the black gates, I insinuated I know a bit about how they are constructed. I took one apart and looked at it under a microscope. That told me quite a bit. It was immediately clear to me why they sound like they do, how they break in, etc.

United States Patent 6379745
Link to this Page: http://www.freepatentsonline.com/6379745.html

Sy: I was looking to design something similar in the lab from pre-existing designs (to create a specific end product), for the US military, ie, Pentagon. They'd of loved it. Problem: I'd be aiding and abetting something I can't tolerate. Problem #2: I'd be providing a very high level solution to a pre-existing problem they have. I'd be a target of theirs or their enemies, at that point. Look up Gerald Bull. I believe he ended up being shot in the face when he opened his door one day.

So I just walked away from it and left it on the ground. I don't like to feel like an Enron or Vatican banker.

It may come as a shock or outright disbelief (this guys a a paranoid freak!, etc) to some of you, but the way that most countries, power people, and corporations or any mixture thereof, deals with outright revolutionary invention....is to kill it dead, as soon and as viciously as possbile -- as 99 times out of 100, it breaks their control system down, it bursts asunder the certainty of their very slow moving (juggernaut) future(s).
 
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