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Copper pipe and silver solder
where ever possible ?
G..
Sent: Tuesday, October 23, 2012 3:14 PM
Subject: LF: XPQ Wasilla reports -
Dear all - thanks for all the comments and reports chaps - and lack
of them is as much of interest too/ I didnt expect much given conditions are a
little early on all paths, and the Alaskan ionosphere is still a little
hot, but looks like I had success down to BC (Jack) and across the Pacific
perhaps.
XPQ went off at 1333z after an overnight run at >1Kw constant
carrier -
The good news is I think Ive discovered the problem with one
bolt joint on a feedthru and will investigate further it doesn't look like the
Brass is the only culprit. Using an IR/laser sighted gun I measured
the temps of the components as best I can and can localize temps to a few
mm
Its around -15C out there at present in air with low humidity - Loop
current 60A which is good. The "hottest" component, apart from the joint, is the
2T:13T transformer at just 9C ! All the current sharing caps are cold and around
1C - power and ERP held within 0.5dB and phase was maintained as far as I can
see.
I dont have a (safe) or effective alternative for a Tx
antennae here - Verticals just dont work as well in a Alaskan Birch/Spruce
forest and the loop is easier, has less potential wx/tuning issues and more
stable by far here in this bespoke location. This loop configuration is the same
as XDW but my geographic and topological environment is very very different to
Oklahoma! Still Im very happy that we can continue the tests as we move
into the winter - time will tell.
Im building a doubler and interface
board for the TS850 at present to provide a locked reference, The TS870 had
already been modified for WOLF tests with John XES way back when - Ive
been using the FT817 as the transverter source and even with the TXCO is just
good, or bad, enough after a long warm up of dot 60 using it at 5.136MHz, but
its sort of a guess and tweek on where the freq will actually go stable. For
last nights test the Freq source was a GPS referenced HP3336B driving the Decca
5501 directly. Heatsink temps on the 3 Decca modules were around 30C, LPF
inductors 37C, though I had the phase meter on top of the LPF vents so this temp
should have been a little lower.
expect more playing with modes
soon - Ill probably take a run at Opera 32 tonight (using the FT817 as the
drive) but will be likely off air on the 24th for the SAQ test.
Laurence
KL 1 X WE2 XPQ Wasilla AK
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