Message-ID: <007901c0a444$81affe20$97b21bca@xtr743187>
From: "Vernall" <vernall@xtra.co.nz>
To: rsgb_lf_group@blacksheep.org
References: <3.0.1.16.20010228102047.2cdfe722@mail.cc.kuleuven.ac.be> <14YH76-07vfRgC@fwd04.sul.t-online.com> <005001c0a43c$479230d0$0a00a8c0@ThreeLakes.ca>
Subject: LF: Re: Interference to ARGO, a surprise
Date: Sun, 4 Mar 2001 13:36:48 +1300
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Larry,

You have found an oddball way of getting unwanted local audio.
> I have been having a bit of a problem receiving LF signals with ARGO, I am
> not able to see the signals due to interference.  I have been looking for
> G3LDO with 60 seconds dits and nil just more and more interference.
>
> Today I did a methodical series of test and I have found that the speaker
I
> have been clip leading into the circuit so I can listen to what is going
on,
> straight noise of course, is in fact reacting to the large blowers I have
> running in my remote site.  The Blowers are the source of interference
that
> has been driving me almost nuts looking for the source.
>
> Have any of the others had local speakers become a visible component in
> their receivning systems?

Also beware of laptops that have onboard microphones.  I was mystified as to
how the Argo screen was apparently working when the audio lead was
unplugged, but it was an audio (sound wave) path via the microphone.

73, Bob ZL2CA