[AMPS] Tune Up of Henry Amps, Prt 1a.

[Jim Reid]

Hello to those interested in this topic.

I have sent this note to a few of you directly,  but it has been
bounced by the reflectors.  I have been told by one of
the recipients,  that the reflector machines believe a particular
character combination I used may indicate a potential
problem,  so the note has not been accepted.

I suspect that the way I have described the Henry  output
plate circuit on to the load may be at fault.  So I will now
call that circuit a "pie",  followed by a "dangling" inductor.

Also,  am breaking the post into  parts, as perhaps the length
was the problem,  just not sure.

But,  I would appreciate any comments from those who might be
able to aid in my understanding the proper tune up procedure.
So,  first a few quotes from the Amp reflector:

Dave, K8CC,  wrote,  in part:

> I've found with my Henry that using the old "dip and load" 
>technique always leads to the best operating condx.

Then,  Dick, WC1M,  wrote:

>These days, I use a hybrid approach with my SB-220. 
>I have an external power meter positioned on top of the amp 
>case, very close to the fixed Ip meter and multimeter, and I 
>set the multimeter to Ig. That way, I can see power output, Ip 
>and Ig at the same time. After setting the drive level, I dip
>the plate (making sure output peaks as well), advance the 
>load control for max output, and repeat until there is no further 
>increase in output. While doing all this, I keep one eye on Ig 
>to make sure it stays within safe limits, reducing drive and 
>retuning when Ig is too high. After this, when operating
>SSB, I try to remember to advance the load control slightly 
>for improved linearity, dropping output maybe 5% 
(recommended by KM1H.)
>
> On my SB-220, I've found that presets (cardboard behind 
>the knobs, with settings marked) work fine....

Next,  Rich, AG6K,  wrote:

"-  It is my opinion that for a Pi-network tank, dip and load is 
not the  right road.  Better to start with heavy loading (minimal 
C-load) to  reduce dissipation in the grid, apply max. drive, 
and tune for max.  P-out." 

End of part 1a.

73,  Jim,  KH7M




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