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Re: [Amps] Drake L4B/8877 Retrofit Problem

To: "w2cqm@juno.com" <w2cqm@juno.com>, <amps@contesting.com>
Subject: Re: [Amps] Drake L4B/8877 Retrofit Problem
From: Rick Stealey <rstealey@hotmail.com>
Date: Tue, 11 Dec 2007 00:54:49 +0000
List-post: <mailto:amps@contesting.com>
Ron,
Did you ever try the exercise of putting an approximately 3500 ohm resistor 
across the tune cap to simulate tube driving Z and looking into the loading cap 
with an antenna analyzer, looking for 50 ohms?
I am in Calif. right now and unable to do any amp work on my 8877 project but 
before I had to come here I did that and had good luck.  In my case I am merely 
trying to see if my tank L taps are set right and if my plate tune cap is in 
the right range.  But my point is, I was able to see a nice sharp dip to 50 
ohms as I tuned the tank caps.  In your case, since all is ok on 20 meters you 
would have something to compare 80 meters with.  Although you obviously wont 
see breakdown you might find such things as stray resonances, bad bandswitch 
conductivity, etc.  
Might be interesting to try.
In my case I am going to a breadslicer for the tuning cap, took out the vac 
variable.  I ordered some padding caps from "Annas CW Store" on eBay and will 
experiment with them in a few weeks.
73
 
Rick  K2xt
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