ORIGINAL MESSAGE: (may be snipped)
On Mon, 7 Oct 2013 02:02:18 -0700, Jim wrote:
>You don?t need 4 ga wire.
>With 1500w rtty, torrids will diss aprx 57 watts whether 1-2-3 cores are
>used... T-225-2A.
>If you want to run 1500w rtty on 160m, Id suggest 3 x T-225-2A stacked.
>For 1500w cw-ssb,
>use at least two of those cores.
>
>## If you are going to convert a monoband SB-220 to 160m, I would not even
>mess with torroids.
>One piece of airdux using 12 ga wire, close spaced is more than ample for the
>job..and it wont dissipate
>a ton of heat like torrids.
>
>Jim, VE7RF
REPLY:
I agree, you don't "need" 4 gage wire, but it will be stiff enough to be
self-supporting - no form needed, just a ceramic standoff at each end and
maybe one in the center if you want a little more rigidity. 3,5 inch
diameter, six inches long. Not much bigger than stacked toroids and air is
free. :-)
To me, Air Dux is a little iffy. Back in the ;90s I had an AL-82 that had
Air Dux coils for 80 and 160 meters and I smoked them (literally) doing RTTY
contesting. The plastic supports melted and the whole thing sprung into a
mess of spaghetti with some impressive arcing. I asked the designer why such
a high powered amp used such wimpy coils and his reply was "Who does RTTY on
160 meters?". A little ironic since he was talking to someone who does.
I tend to be conservative in such things. I want to build things once and
never have to fix them, ever. Even if you don't plan to do 160 meter RTTY,
who knows who might want to do it sometime in the future?
BTW, only one "r" in toroid.
73, Bill W6WRT
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