Hi Mike
I've just set it going now. I can hear it clearly in shack on 8.9khz (JRC
JST245 fed via Datong up converter on 28.0089) S9+40dB The Rx antenna is
a 30m long delta loop in a silver birch tree above the ground run of the
wire, so no great surprise there. Distance ~ 8m!
Yesterday I drove around the village using a simple 10m mobile whip via a
datong up converter into my IC706mk2g and could receive it audibly out to
about 100m. On my drive (50m from wire) it was S9, but under the drive is a
big steel mesh that is cross bonded to my earthing system so again no
surprise
Moving off the drive (mesh) the signal dropped to S7
Much beyond 100m it was not audible above S3 background noise, though
obviously the Rx system was hugely sub-optimal and I was relying on "mk1
human ear!)
The TX system is a ELAD FDM-duo SDR transceiver output via the 0dBm port
into a "G3XIZ interstage amp which takes the power up to ~ 1 watt. This
is fed via 10m of coax into the garage into a Hafler P4000 audio amp and
that gives about 400W out via a 8ohm to 50 ohm matching txfrmr (John W1TAG
design). Coax from that goes to a connection - braid to earth near to amp
and then core to a 35m long wire (RG6 actually - shorted braid to core at
both ends) connected to a further good earth at bottom end of garden.
The wire runs approx E-W.
As you are south of me and hence orthoganol to the wire run, it may be even
harder for you to detect.
I'm txing G7NKS test IO92ub etc for about 1.5 mins at 5wpm using DM780 (the
data component of HRD v5). This is set to repeat at 20 second intervals.
Best of luck and see if you can spot me (I won't hold my breath as I know
it's a bit heath robinson set up here!)
with best regards
Jim
Dr. Jim Cowburn G7NKS IO92ub
Biggleswade UK
Details on QRZ.com
-----Original Message-----
From: Mike Dennison [mailto:[email protected]]
Sent: 20 August 2017 11:26
To: James Cowburn
Subject: Re: LF: G7NKS txing on 8.9kc CW 5wpm 300w into a ground loop 35m
long
Jim, I miised your email yesterday but would be happy to look for your sigs.
We are quite close so may be a chance. It will take me half an hour or so to
reconfigure my receiver/antenna. Busy today, however, so perhaps a test next
w/e, or even during the week?
Mike, G3XDV
==========
> Hi All
>
> I´m running a VLF test beacon on 8.9kc . Ground loop electrode
> system. 35m long
>
> Any spots welcome (if unlikely!)
>
>
>
> with best regards
>
>
> Jim
>
> Dr. Jim Cowburn G7NKS IO92ub
>
> Biggleswade UK
>
> Details on QRZ.com
>
>
>
> ---
> This email has been checked for viruses by AVG.
> http://www.avg.com
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