Message-ID: <003e01bee437$206b7500$0200a8c0@test>
From: "Dave Brown" <tractorb@ihug.co.nz>
To: rsgb_lf_group@blacksheep.org
References: <37B123A5.F924C09D@cableol.co.uk>
Subject: LF: Re: Correction to; Measurement of loop antenna current
Date: Thu, 12 Aug 1999 08:21:35 +1200
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Forget the numbers I quoted re my LF loop in previous posting; in defence
all I can say is I was first licensed in mid sixties and been member of RSGB
since 68. Draw your own conclusions!!!

 For some reason I keep forgetting that I actually have two conductors in
parallel in the loop. The 5 ohms rf resistance I quoted was the figure for
the original single conductor loop.  With two conductors in parallel the
figure is close to 1.25ohms.  Corresponding DC figure is just over 0.1 ohms.
The present loop matching xfmr has a 13 turn (50 ohm) primary and 2 turns on
the loop side secondary. Never been quite sure why it dropped to quarter of
what it was originally rather than just half.  Anyone else had the same
experience?

 Anyway the other figures are basically correct,  just under 25 amps loop
current for the 750 watt tx out figure. I do push it to 30 amps on occasions
but the poor old pair of 813s won't take too much of that!

73
 Dave
ZL3FJ