[Lowfer] 73k problem

[Stewart Nelson]

Hi all,

The Loran spec is at
http://www.navcen.uscg.gov/pubs/loran/sigspec/Default.htm .

The key item is that at least 99% of the radiated energy must be
in the band 90 to 110 kHz.  Unfortunately, pulse power is as high
as 1600 kW (most US sites are 400 kW), so that allows up to
16 kW of QRM :)

The folks at Megapulse took the nifty table down from their site
last year.  When I discovered this, I found a copy in Google's cache
and saved it: http://www.scgroup.com/ham/lorantable.html .

Data for US chains only, but probably more reliable than the above,
is at http://www.navcen.uscg.gov/loran/LoranSelectChain.htm .

73,

Stewart KK7KA


----- Original Message ----- 
From: "Lyle Koehler" <lyle@mlecmn.net>
To: <lowfer@mailman.qth.net>
Sent: Monday, December 09, 2002 6:19 AM
Subject: Re: [Lowfer] 73k problem


> The specifications for the Loran-C pulse shape can be found somewhere on the
> US Coast Guard navigation site, but I've lost the bookmark. Seems to me the
> specified rise time is 2 microseconds or less, but I can't say for sure. All
> I remember is that, when I calculated the envelope of the spectrum, it
> explained why I could hear the chickens clucking for a long way on either
> side of 100 kHz. In my case, the interference is from the 800 kW Loran
> station at Baudette, MN, about 150 miles north of me. I have to null the
> signals with the loop in order to listen on either 73 or 136 kHz.
> 
> Lyle, K0LR
> 
> _______________________________________________
> From the Lowfer mailing list
> Send messages to: Lowfer@mailman.qth.net
> To sub/unsub visit: http://mailman.qth.net/mailman/listinfo/lowfer
>