Message-ID: <B203FE8F5451491C81A9DCB5C449FF37@gnat>
From: "Alan Melia" <alan.melia@btinternet.com>
To: <rsgb_lf_group@blacksheep.org>
References: <CAA8k23R+Q-4zD50pXGZ5XMEdM7rnFvp844f_nUAuKMfuAs+2PQ@mail.gmail.com> <8D2F5CEE86A9058-14FC-16B19E@webmail-vm002.sysops.aol.com> <2062584.LhDGbAj14s@zv5000> <56561D1B.7080201@abelian.org> <CAA8k23SewT7EmGD64Zui+JW2GL4YOykCeEuvnZdStGMo-prREg@mail.gmail.com> <565634BC.50806@charter.net>
Date: Thu, 26 Nov 2015 00:55:48 -0000
MIME-Version: 1.0
Subject: Re: LF: EbNaut and The Cat / Take 3
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Status: O

Also Brian CT1DRP tramsmit phase locked DFCW from Porto using Andy's 
Synthersiser with RS-232 control, because I wrote the code in Power Basic 
for Windows, which Brian took a few bugs out of. The code was timed by 
putting the 1PPS on the interupt pin of the PIC, and the freq was locked to 
10MHz GPSDO.  I think he was received by Bill deCarl,and probably others. He 
also did a test with Peter over 48 hours with Peter measuring the phase. I 
am not sure if he ever tried BPSK though......although Bill certainly talked 
about it.

Alan
G3NYK

----- Original Message ----- 
From: "John Andrews" <w1tag@charter.net>
To: <rsgb_lf_group@blacksheep.org>
Sent: Wednesday, November 25, 2015 10:22 PM
Subject: Re: LF: EbNaut and The Cat / Take 3


> Andy,
>
> I recall doing a series of 137 kHz experiments with Peter Martinez using 
> PSK, with the sending end being triggered by 1PPS interrupts from my HP 
> GPS receiver. Somewhere here I have the 8051 code I kept modifying. We 
> were using bit timings of 30 seconds or so. If memory serves, there were 
> no wildly successful results, but he certainly copied my signal on some 
> nights that would have been rough for QRSS30.
>
> John, W1TAG
>
> On 11/25/2015 4:32 PM, Andy Talbot wrote:
>> Its a pity we no longer have 73kHz
>> Back in the early 1990's when that band was being proposed, one of the
>> ideas put forward as an argument for getting it  was a link budget
>> worked out showing how TA might be just about possible using coherent
>> PSK with low symbol rates - something that would have been very
>> difficult for amateurs in those early days of DSP.
>>
>> The TA path was managed eventually once, or perhaps twice AFAIR,  by
>> very slow QRSS at high power and, I think, a period of enhanced
>> propagation.   Suspect it would be easy enough on EbNaut now.
>>
>> The PIC 1kHz bandpass digitiser is a very neat way of doing the back end
>> of an LF narrowband SDR, allowing embedded GSP timestamp and completely
>> independent of all the nasties associated with soundcards
>>
>> Andy  G4JNT
>>
>> On 25 November 2015 at 20:42, Paul Nicholson <vlf0403@abelian.org
>> <mailto:vlf0403@abelian.org>> wrote:
>>
>>     Markus wrote:
>>
>>      >
>>
>>     take long to exhaust the permutations.
>>
>>     And what are the limits at LF?   How far do amateur signals go?
>>
>>     For that matter, how far does this mailing list reach?
>>     How to interest more experimenters... away from Europe and
>>     North America.
>>
>>     Was reading about lowFER, severe limits on antennas and input
>>     power.  Now that could be interesting.   Do lowFER signals
>>     reach Europe?
>>
>>     Lacking DX stations, the only option is some serious QRP.
>>
>>     Can we think of something interesting enough to drag Andy
>>     away from his GUI?
>>
>>     --
>>     Paul Nicholson
>>     --
>>
>>
>