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[Amps] equalizing resistors

To: <amps@contesting.com>
Subject: [Amps] equalizing resistors
From: 2@mail.vcnet.com (Richard)
Date: Fri, 1 Mar 2002 08:18:13 -0800
>I am replacing the filter cap in the hv section of my Thunderbolt. I will 
>be using 2 caps in series. The power supply filter is the choke input type 
>using a swinging choke. It supplies 2200 volts. Do I need to add equalizing 
>resistors across each cap. 

?  I would.  It's a reliable way to bleed off the caps, plus it applies 
equal V to each.    

>Depending on who I talk to, Ive been told I do 
>need them and than again I dont need them. Which is correct. If I do need 
>them, what size should they be. 100k at 10 watts is what Ive been told.

?  10W, 100k? resistors are not ordinarily able to handle even 1000V - 
even though that's 10w [read the fine print in the specs].  Also, 1100V = 
12.1W @ 100k?.  My guess is that whoever told you this does not have a 
firm grip on Ohm's Law.  

?  Also, a swinging choke filter works ok with AM-linear service because 
DC current drain is constant.  However, for SSB, the current is not 
constant, so, if one checks transient regulation with a DC oscilloscope, 
it is not ok,  This is why Henry, Collins, Harris and the rest never use 
a swinging choke filter in their linear amplifiers.  For good transient 
regulation, either a resonant-choke filter or a capacitive filter are the 
only games in town.  

cheers, Bill

-  R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K, 
www.vcnet.com/measures.  
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