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Message-ID: <001301c6bfe1$e657d320$0300a8c0@lark>
From: "Alan Melia" <alan.melia@btinternet.com>
To: <rsgb_lf_group@blacksheep.org>
References: <001401c6bfcc$56290400$75be3b3e@fujitsu>
Date: Mon, 14 Aug 2006 21:40:32 +0100
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Subject: LF: Re: antenna current meter troubles
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Hi Dick I am not sure what the mechanism is. Jim seems to think it is RF
getting into the diode and meter circuitry of the secondary, but I am not
sure. I have not had enough power to experiment with this, and compare with
a thermoammeter. You might try sticking the meter at the bottom of the coil
to ground the same current should flow there. Otherwise assumings its a
magnetic effect on the ferrite.....what about 2 coil diameters away at least
??

Cheers de Alan G3NYK

----- Original Message -----
From: Dick <knaap159@zonnet.nl>
To: <rsgb_lf_group@blacksheep.org>
Sent: 14 August 2006 19:05
Subject: LF: antenna current meter troubles


Well it seems very likely that my antennacurrent meter is not working as it
should be.

The ringcore is likely much too close to the main loading coil.
It's less than 10cm (4 inch) away from the coil.

I have to make a new external meter that can be placed away from the loading
coil.

Anyone with experience about minimum distance between loading coil and
antennacurrent meter,
and how about shielding the antennacurrent pick-up core with a metal (not
grounded!) screen?

73

Dick