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<DIV>Hi Doug</DIV>
<DIV> </DIV>
<DIV>I think that you are referring to C59 across the high voltage secondary of
mains transformer T-1. This capacitor must have a voltage rating in excess of
1.414 times the rms voltage across it plus an allowance for the mains supply to
rise to its maximum tolerance and then some additional contingency. The
1600v rating seems very reasonable to me.</DIV>
<DIV> </DIV>
<DIV>You can get high voltage ceramic capacitors and use two or three in
parallel to make the total capacitance required.</DIV>
<DIV> </DIV>
<DIV>I assume that the original capacitor was intended to reduce spikes from the
mains as it is a large value and probably the wrong type of construction for
high frequency RF decoupling.</DIV>
<DIV> </DIV>
<DIV><FONT lang=0 size=2 face=Arial FAMILY="SANSSERIF"
PTSIZE="10">73<BR></FONT><FONT lang=0 color=#0000ff size=4 face=Arial
FAMILY="SANSSERIF" PTSIZE="14"><I><BR>Bob</FONT><FONT lang=0 color=#000000
size=2 face=Arial FAMILY="SANSSERIF" PTSIZE="10"></I><BR>Bob F Burns G3OOU,
G-QRP 6907, @BobFBurns<BR>Crystal Palace Radio & Electronics Club: <A
href="http://www.g3oou.co.uk/">www.g3oou.co.uk</A><BR>Technical web site: <A
href="http://www.qsl.net/g3oou">www.qsl.net/g3oou
<DIV> </DIV>
<DIV>
<DIV>In a message dated 25/10/2017 01:30:10 GMT Standard Time,
dkdavies3@gmail.com writes:</DIV>
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<DIV dir=ltr>I need to replace a buffer capacitor in the power supply
rectifier circuit in an old HW-10 Shawnee I'm trying to restore. It is a
paper cap, oil filled and the value is 0.047uf @1600 volts. I can find a
0.047uf one but nothing rated at 1600 volts. Is this a critical value or
can I replace it with a polypropylene one rated at 650 volts?
<DIV><BR></DIV>
<DIV>Doug</DIV>
<DIV>VE7DRF</DIV></DIV><BR><BR>_______________________________________________<BR>Heath
mailing
list<BR>Heath@puck.nether.net<BR>https://puck.nether.net/mailman/listinfo/heath<BR></FONT></BLOCKQUOTE></DIV></A></FONT></DIV></FONT></BODY></HTML>