From: Terry GW0EZY <gw0ezy@sky.com>
To: <rsgb_lf_group@blacksheep.org>
References: <CAA8k23Rn9WpQM3Ukf=cq5-bLmWy+o4SEsH2abf7cAX=BpLWExQ@mail.gmail.com> <op.v6k16ktpyzqh0k@pc-roelof> <033201ccbcab$5c5fe640$1502a8c0@Clemens04> <op.v6mtuugnyzqh0k@pc-roelof>
In-Reply-To: <op.v6mtuugnyzqh0k@pc-roelof>
Date: Sat, 17 Dec 2011 14:00:38 -0000
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Subject: LF: Wellbrook Litz and Loading
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First of all thanks to Andy for starting the Wellbrook discussion - it has
been very useful for me.

James - thanks for the information on the pros/cons of using Litz wire.
Although it seems obvious now, I hadn't realised the meaning of 10/44.

Mal - thanks for your helpful advice and info on your antenna loading
arrangements. I am still trying to picture it all in my mind but it seems
like the sort of relatively simple system I'm looking for - especially
keeping to 50 ohms. I have yet to find a supplier of the metal lined CH pipe
(Srewfix B&Q??)

Thanks to Chris and others for the links to potential replacement DIY
amplifiers for the Wellbrooks. I've downloaded the available info and look
forward to trying several of the designs.

Roelof - I'm fascinated by your description of the "post-mortem" on your
dead Wellbrooks. I am particularly interested how to separate the aluminium
loop from the preamp box without damage to the loop. I was tempted, some
time ago, to use some Toluene offered by a friend to remove the potting
compound. I decided against as it seemed a highly toxic and dangerous
procedure! Maybe I can contact you off-line for final details of the
dissection?

Clemens - The Wellbrook was probably damaged when I was testing a friend's
FT1000 at 200 Watts into a 30-17-12 dipole with centre about 3 metres
separation. Normally I disconnect the Wellbrook PSU when Tx on hf but in the
excitement of playing with a new toy I forgot. An expensive and annoying
mistake as I had received the loop as a present from my XYL about 10 years
ago. It is not completely dead - but has lost ~20 dB sensitivity.

73 Terry