Stewart
I don't know about pirates but there has been plenty of guesswork,
imagination, speculation and visions seen on LF over the years, some even
claim
miracles.
No ID just speculative carriers seen and often wrong conclusions drawn,
don't believe everything that some claim on LF.
G3KEV
----- Original Message -----
From: "Stewart Bryant" <[email protected]>
To: <[email protected]>
Cc: "Chris" <[email protected]>
Sent: Wednesday, October 20, 2010 4:41 PM
Subject: Re: LF: Re: Re: Re: Re: Variometer
> On 20/10/2010 14:45, Chris wrote:
> > Hi Mal,
> > Yes, so I now understand, but it wasn't a 'full blown' repeater, as you
> > say, more a remote RX like a grabber.
>
> Exactly, it was an experimental system (MB7LF) that we ran for a while
> and demonstrated at the HF convention, which received on 136KHz and did
> a linear translation to 144MHz. This was use to overcome local RX
> noise. We had a couple of real cases where local noise was a problem -
> one at G3GRO who got huge ingress noise from a BT line to the local
> hospital and the other was the HF Convention where noise from the
> computer room wiped out 136KHz.
>
> The service could be compared to a short range version of the modern
> Internet grabbers, though it was much closer to a remote SDR because
> you could tune the whole band remotely in parallel to other users.
> However, it was deployed at a time when far fewer people had
> Internet and the bandwidth available was much lower than it is today.
>
> > Thing is, nobody had to use it if
> > they didn't want to. Still can't see how it would attract 'pirates'.
>
> It's didn't. The "pirate" thing was a storm in a teacup.
>
> There was one event, one weekend, where someone did an experiment
> involving a low power signal generator a small antenna and a morse
> keyer to try the system out (unfortunately they accidentally had the
> keyer is some strange mode that gave out random characters). They only
> expected to get to Crawley, but got to Wales and were heard by Steve.
> Once the problem was identified they shut down the experiment.
>
> I can't remember who it was, but it was not one of the group that
> deployed MB7LF.
>
> - Stewart/G3YSX
>
>
>
>
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