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[Amps] SB220 Odd problem: UPDATE

To: "amps@contesting.com" <amps@contesting.com>
Subject: [Amps] SB220 Odd problem: UPDATE
From: Shane Youhouse <kd6vxi@gmail.com>
Date: Thu, 12 May 2011 07:45:52 -0700
List-post: <amps@contesting.com">mailto:amps@contesting.com>
Finally got down to brass tacks on my SB220 (ie, got enough done to where I had 
some time).

Grid current I meter would read 30 mils, keyed, NO tubes.  Read the value of 
the .82 ohm shunt, its 33 ohms.  New one on the way.

Also replaced every finger on the bandswitch.  #2 hardware works fine for those 
interested.  MUCH better tuning.  Removed HALF the turns on the 10 mtr input, 
put a 120pf cap on in and out, 65  watts on 10 now gives 700 out..  Centered 
the new input on 26.3, gives a nice broad coverage of 12 and 10, under a 2, 
WELL under a two to 1.

I'm also going to replace the HV shunt resistors, and increase the amount of 
resistors by two, in order to lower voltage impressed upon any one resistor.  
Bleeders all checked out.

Rewiring the CT to prevent smoking fil xformer will be done when I put the 
resistors in...  Any other mods?  Grids are already directly grounded.

Carl, whats the value of the SM you put from 80 to 10?  I DO NOT want to 
replace those fingers again! LOL...

Once this one is finished, time to add some screen voltage to the 4-1000 in the 
rf-103....  Pulled out the Lambda supplies, tired of stubbin the toes! LOL


Transistors have ratings, tubes have guidelines!

--Shane  
Kilowatt Delta Six Victor Xray India
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