On Thu, 24 Apr 1997 09:51:16 EDT km1h@juno.com writes:
I will repeat myself for your benefit Tom plus that was all done about
10 years ago.
Recent work with the SB-220 on 6M leads me to believe the plate circuit
reaps the most benefit, primarily due to direct point to point
wiring...no gobs of stray C and L and wiring losses.
I also modified the Tune caps for lower minimum C on 10-15M to work with
the higher L's on those old HF conversions.
Monoband 220's on the bands below 20M show no improvement over the stock
configuration EXCEPT for total lack of flakyness...no arcing , spitting,
etc.
I never did a step by step evaluation then...it was an all at once
conversion. My current 6M conversions, however, have gone thru a very
careful evaluation and evolution.
Over several years I have placed the input circuit of 6M conversions from
the end of a 12" hunk of coax to right at the socket....very little
difference, if any, when tuned to compensate. At 100W of drive any input
setup gives 1100-1200W out.
The SB220 layout lends itself to a great 6M conversion...the parts fit so
well.
But your query was about HF so you can extrapolate my comments above.
Sorry if the above a bit disjointed...I got real hung up in the Editor!
73...Carl KM1H
>I am certain that just going to an optimum Q played only a small part;
>the overall design/layout of the 220 was inefficient IMO.
>My "ratty" LK-500ZC runs 1200-1300W on all bands by comparison, has
>never arced or blown parasitic suppressors. Pretty decent design and
>good components considering its selling price.
>
>73....Carl KM1H
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