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   rec.audio.tubes      Tube-based amplifiers... that go to 11      52,877 messages   

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   Message 52,566 of 52,877   
   oldschool@tubes.com to All   
   What type of capacitor should I use?   
   09 Mar 17 19:01:46   
   
   XPost: rec.antiques.radio+phono, sci.electronics.repair   
      
   What type of capacitor would be the best match to replace the old   
   paper/wax caps in old tube gear?   
      
   I am not referring to the electrolytics, those I know need to be   
   electrolytic caps. I am referring to the inter stage caps, such as .01   
   .05 .1, .005 and so on.....   
      
   The object is to replace all the caps in an old tube radio, or any other   
   tube stuff.   
      
   Yes, I know this topic was sort of discussed a few weeks ago, and I   
   recall hearing that any of them would work, but that does not really   
   answer this question. Sure, they may all work, but what type would be   
   the closest match to the original paper/wax types?   
      
   From what I know, those caps were made from paper and a metal foil   
   rolled up and coated with wax. So, what is the nearest similar type?   
      
   From that last discussion, I know I left that thread sort of puzzled   
   because all caps seem tp contain "poly" (which means plastic). I am   
   thinking that what seems to be the closest would be whatever plastic   
   replaces the paper, and a foil. From what I understand, some caps do not   
   have a foil, but rather some sort of metallic material that is coated or   
   sprayed on. Those are probably not what I would want to use, because   
   they are not similar to the originals.   
      
   I am fully aware that the voltage MUST be the same or higher and the uf   
   must be close, such as .047 to replace .05. Also for tube circuits,   
   axial leads are preferred.   
      
   Then too, looking on ebay and other sources, I see a lot of very   
   expensive caps which are intended for high end audio amps. For my needs,   
   I will not pay $29.99 for one cap, and yes I have seen them cost that   
   much.   
      
   I am seeing some no-name cheap China caps selling for as little as 20   
   cents each. While I like to save money, I'd really rather spend $1 each   
   for something like the Orange Drops, which have been around a long time   
   and seem to be good quality, despite the fact they dont come in axial   
   form. But they generally can fit into most places.   
      
   I will only be replacing those paper/wax caps and the electrolytics. I   
   wont touch any mica or silver mica types, unless they appear to be bad   
   (I will probably test them though).   
      
   One that I do recall, are the so called Mylar, which I think were the   
   first ones that were made to replace the old paper caps. I guess they   
   now changed that name to something "poly" also.....   
      
   What would you recommend or use?   
   Web url's appreciated for lower cost AMERICAN made caps.   
      
   One last thing, I found some cap assortments on ebay. 150 or 200 caps of   
   assorted values, labeled as NOS (New old stock), but they are NOT the   
   paper/wax kind. Since I have no spare caps, and just want an assortment   
   on hand, I was thinking about buying one of those. I would NOT buy NOS   
   electrolytics, but for the interstage types, I might consider this, just   
   so I have an assortment of caps on hand..   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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