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From: "Peter Martinez" <peter.martinez@btinternet.com>
To: <rsgb_lf_group@blacksheep.org>
References: <000001c65d80$ccb30840$e6a4c593@RD40002>
Date: Tue, 11 Apr 2006 17:25:58 -0000
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Subject: Re: LF: Rugby LORAN measurement?
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>From G3PLX:

When Rugby LORAN failed to shut down last Tuesday, it occured to me that I 
could adapt my coherent locking program to measure the LORAN SNR even while 
LORAN was transmitting. I measured -5dB, that is, LORAN (from Rugby) is 5dB 
below the noise level (without LORAN). G3NYK also tried it and gets -2dB. He 
is closer to Rugby than I am.

This morning I noticed that Rugby LORAN went off between 10:15 and 10:45 
utc, and during that gap I measured the noise level, and again when it came 
back on. The difference was 1.2dB, which agrees with the above measurement 
of the LORAN and the noise separately.

I am not sure that it would be easy to do a large-scale survey of LORAN 
noise levels with my program because it's not easy to set up, and there will 
be a large variation in the noise levels at different locations, but if 
anyone would like to experiment with the program I wrote to do it, contact 
me off the reflector. It needs an ordinary PC with a good quality soundcard, 
and a 136kHz receiver with good frequency stability.

73
Peter