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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