[Heathkit] DX-100B Capacitor Question

[Richard Knoppow]

----- Original Message ----- 
From: "Bruce Spacer" <wb8vcm at hotmail.com>
To: <heathkit at mailman.qth.net>
Sent: Wednesday, April 11, 2012 6:17 PM
Subject: [Heathkit] DX-100B Capacitor Question


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> I am rebuilding a DX-100B and saw a posting that it would 
> be a good idea to replace the 68 pF mica between the 
> driver and final.
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> The existing capacitor is a molded mica Sangamo.  It has 
> no color codes, but on one side is stamped "68 5%".
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> On the other side, it is stamped "2000 VW" (not WV).  It 
> is arranged like a 6 dot format, and when you hold it with 
> the arrow pointing right, the digit "2" is molded into the 
> upper middle dot.
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> Is this a 2000V part ?  A quick check of the Mouser site 
> shows the typically available CDE micas (CDV19) are only 
> rated up to 1000V.  Any suggestions for a replacement ?
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> Thanks,
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> Bruce
> WB8VCM
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     I wonder what this is. Sangamo made plain mica HV caps. 
These do not use silver plating as the electrodes but have 
foil in them. The lack of markings suggest it.  While some 
silvered mica caps suffer from migration of the silver 
plating or oxidation if they are not well sealed the foil 
stack kind do not.  Not all are of equal quality and I 
remember Micamold having problems but not Sangamo.


--
Richard Knoppow
Los Angeles
WB6KBL
dickburk at ix.netcom.com