Help!! Polypropylene capacitors confusion! KP or MKP???

[Nordic]

Yep Fotios in plain english, he did pay you a slight compliment for persisting in your quest....

 

[Eric Juaneda]

Hi Fotio, hi Lumba,

I feel admiration in Lumba's comment, nothing ironical!

Hi guys,
there are problems with PTFE (teflon): availability, price, values (only small values are manufactured).

You can find to the French manufacturer SCR Teflon capacitors from 0.22µF to 10µF.

Sample price for 10 pieces. ("FEP Supersound cap")
1µF - 24Euro
2.2µF - 38Euro
4.7µF - 66Euro
10µF - 126Euro

Out of price, but big values. Unity price is twice.

Eric

 

[gootee]

(This might be slightly off-topic. But, ) If anyone ever needs a Teflon capacitor with a relatively SMALL value, such as somewhere in the lower pF range, a relatively cheap and easy solution is to use a short piece of shielded coaxial cable that has Teflon dielectric (especially if such cable is already available). Connect the center and outer conductors from one end, as the capacitance, and then trim the length of the other end, until you have the desired capacitance. That was suggested by the-one-and-only Bob Pease, of national.com .

- Tom Gootee

http://www.fullnet.com/~tomg/index.html

 

[Lumba Ogir]

Thank you Nordic and Eric for the support. It was needed.

Eric,
thanks for the information, I`ve never seen such values, last time I looked was years ago.

fotios,
look, you are an exceptionally kind person, there is no doubt in my mind, someone to have as a friend. I have never meant to hurt you deliberately, but I have a unpolished polemic style. Not nice at all. I regret it and apologize. I still hope the damage is reparable.

 

[fotios]

Thank you Nordic and Eric for the support. It was needed.
fotios,
look, you are an exceptionally kind person, there is no doubt in my mind, someone to have as a friend. I have never meant to hurt you deliberately, but I have a unpolished polemic style. Not nice at all. I regret it and apologize. I still hope the damage is reparable.

No problem friend, no problem. Sorry also me for the misinterpretation.
Regards
Fotios

 

[john curl]

Fotios, I think you are on the right track, but if I were you, I would stick to polypropylene, polystyrene, or teflon. Teflon is always expensive and large. Trust me. I have Teflon caps in front of me that cost at least $40 each, factory price, and they are of relatively small value.
For values over 1uF, metalized polypropylene can be the best solution, overall. It will be significantly smaller and cheaper than teflon or polystyrene, and still have very low dielectric absorption. PPS is interesting for minature applications, where size is VERY important, but it will not be as good.

 

[Eric Juaneda]

big polystyrene capacitors

Hi John,

For values over 1uF, metalized polypropylene can be the best solution, overall. It will be significantly smaller and cheaper than teflon or polystyrene...

Do you know which manufacturer produce big values (1µF, 2µF) from polystyrene capacitors? I know that Conrad Johnson use it in their designs.

regards,

Eric

 

[coresta]

None, polystryrene are oldfashion nowdays as they don't afford the "modern" ways of ROhS solder. I found EMZ styrene caps in Germany but size is small : you can get 250v /low capacitance or low WV (63v) for rather high capacitance ... Don't forget FKPs , the best (1,2kV WV )