Envelope-to: dave@picks.force9.co.uk
Delivery-date: Tue, 18 Oct 2005 00:52:42 +0100
Message-ID: <005801c5d375$cdbe6ad0$0702a8c0@parissn2>
From: "Stewart Nelson" <sn@scgroup.com>
To: rsgb_lf_group@blacksheep.org
References: <435402AB.7080004@g3ysx.org.uk>
Date: Tue, 18 Oct 2005 01:52:14 +0200
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Subject: LF: Re: Recording of Rugby Loran-C
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Hi Stewart,

The USCG spec for LORAN requires that at least 99% of the
radiated energy be contained within the 90 to 110 kHz band.

Assuming that limits for the 250 kW station at Rugby
are the same, then it is permitted to emit 2.5 kW
pulses of QRM into spectrum licensed to others.

I know of no other service that allows spurious
emissions to be suppressed by only 20 dB.

73,

Stewart KK7KA

----- Original Message ----- 
From: "Stewart Bryant" <stewart@g3ysx.org.uk>
To: <rsgb_lf_group@blacksheep.org>
Sent: Monday, October 17, 2005 9:59 PM
Subject: LF: Recording of Rugby Loran-C


> Has anyone got a recording of the effect of the Rugby
> Loran-C on the 136KHz band?
> 
> I am at the International Telecoms Synchronisation Forum
> where NPL were talking about Loran-C as a possible
> alternative to GPS for frequency reference. When I
> asked the speaker about the pollution he said that he
> thought it was confined to +/- 10KHz, and was quite
> surprised when I explained about 136KHz. Interestingly
> someone from the BBC spoke to me afterward and said
> that there was a problem with interference with Radio4
> in the Rugby area, that was attributable to the
> Loran-C Tx.
> 
> Anyway, if anyone has a recording I will play it to
> the NPL speaker to show him what is going on.
> 
> 73
> 
> Stewart