Date: Wed, 7 Jun 2000 09:28:12 -0400
From: "DEREK ATTER" <DATTER@compuserve.com>
Subject: LF: Decca Loading coils, 1Kw Transmitters, Litz wire etc.
To: rsgb_lf_group@blacksheep.org
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The Crawley Club have managed to collect a number of  items of hardware
from the redundant Decca stations before they were scrapped. These  include
several of the 1.2Kw  transmitters,  a considerable amount of Litz wire of
various gauges, one or two variometers, several of the large loading coils
described on Mike G3XDV's website plus a number of high stability 5Mhz xtal
oscillators.

   The Club propose to offer these for disposal among the LF fraternity at
modest prices to cover the transport costs from site plus a donation to
local clubs for their efforts in collecting and storing the equipment.  The
the Club does not  wish to get  involved in arranging delivery so equipment
will have to be collected from Crawley.  Anyone interested please contact
me for information on details on prices etc. by phone on 01293 520424 or by
E-mail at. (datter@compuserve.com) 
    The Crawley Club are hosting the South Eastern session of the 
Microwave Round Table this coming Sunday, 11th June.   The morning session
starting at 10 am will include a small 'bring and buy' sale at which the LF
items will be also be available.       Information on the ex-Decca items
will also be posted on the Crawley Club website at
www://http.bigfoot.com/~crawleyarc/

Further details of the some of the hardware:

Tranmitters :      1.2Kw RF out from 3 separate PA modules each with 4
power MOSFETs  operating in class "D" in a bridge   configuration.  The
units are rack mounted with integral driver and protection circuitry in
each module. RF drive input 3V  pk-pk.
  DC input supplies 67.5V about 25A and 24V at 1A.  Technical info and
circuit diagrams are available.  Depending on demand we  could split up
some TX units into individual PA modules each nominally rated at  400W but
believed capable of about 600W each.
 
Litz Wire :  In addition to the large loading  coils ( about 900mm diam  x
250mm wide with 729 strand Litz wire) we have a variety of different gauges
from quite thin up to some about 3mm diam double cotton covered with large
number of strands. Probably the most interesting to LF'ers  is a quantaty
of  2mm and 3mm diam Litz wire with a thin outer sheath of polythene or
similar (may be PTFE ?) which will have a much higher insulation rating
than the usual cotton covered  variety which will reduce turn-turn voltage
breakdown for loading coil use.
                73 de Derek Atter,  G3GRO