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[AMPS] Re: CW/SSB Tune Up

To: <amps@contesting.com>
Subject: [AMPS] Re: CW/SSB Tune Up
From: 2@vc.net (2)
Date: Wed, 10 Oct 2001 06:57:07 -0700
>
>Hi again,
>
>And thanks a bunch to the several who have commented
>and made specific tune up recommendations!  Have
>followed them this morning.  Rich,  I chickened out at
>just about 345 watts of drive,  hi.  

//   The 3cx3000A7 is rated at 2.5A.  If one drives it to less current, 
one will not get the right E/I ratio for the extant tank.

> The grid current was
>approaching/bit exceeding 300 mA; Henry manual says
>to not exceed 350 mA.  

//   Eimac rates the 3cx3000A7 grid at 225w.  Typical cathode-grid 
potential is c. 190Vrms.  With 1000mA of grid-current one would be 
dissipating c. 190w in the grid.  
However such grid-current would be quite likely to make for less suds 
out.  Thus, the best policy is to tune for max out with max in.  

> at All of this into the Bird
>load,  of course.  Bird 43 with a 5kW slug was of no use,
>it is way too slow and does not respond to the 50 wpm
>dits.

//  With pulse tuning the 43 works a relarive indicator, which good 
enough.  
>
>Anyway I found that once the tune and load controls were
>at resonance,  they did not seem to need to be tweaked
>as the drive was increased beyond 100 watts or so.  

//   If I-anode changes and E-anode is constant, RL changes.

>
>Hope this is correct,  ...

-  R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures.  
end


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