Return to KLUBNL.PL main page

rsgb_lf_group
[Top] [All Lists]

Re: VLF: 300 mA on 8270 Hz

To: [email protected]
Subject: Re: VLF: 300 mA on 8270 Hz
From: Paul Nicholson <[email protected]>
Date: Tue, 26 Sep 2017 11:56:10 +0000
Dkim-signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=abelian.org ; s=default; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:To:Subject:Sender:Reply-To:Cc: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=fjnBB2AVTFXqByFv+4/FT3/shQY7FbT8Tn+jtLRf3SM=; b=tg3p144IPfF7xN+eLMyphV6Onv jg52SGgL3t2eegL2TmbpCi11PcZnLBIci7motK/8Y48Jo7YmJnKZu2SQhXpyIvrwkaOqH6WGao4qj MyigFywOkxL2kGPHSy6EKl0cid09m6O8PWasPJ3Qw/jDNjZRnXQ+Ma1zUNU+vw3tsao0=;
In-reply-to: <[email protected]>
References: <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]> <[email protected]>
Reply-to: [email protected]
Sender: [email protected]
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1
Just got back from a week's camping in Wales on Shell Island.
Chatted with a radio ham who was camped nearby, saw his antenna
poking up above the sand dunes.

My rx runs happily while I'm away - my hobby is almost fully
automated, it doesn't need me any more!

So now there are all these messages to decode... Ah yes I am
needed - but only to read the emails and run the decoder.

Stefan wrote:

> f = 8270.005000 Hz
> Start time: 22.September.2017  06:00:00 UTC
> Symbol period: 24 s
> Characters: 12
> CRC bits: 16
> Coding 16K21A

E-field is recording from the new rx but is un-calibrated so I
can't use it for decodes just now.  So the following is just
using the loops:

 2017-09-22: +0.4 dB phase 126.0 list rank 8225;
 2017-09-23: +1.6 dB phase 131.0 list rank 0;
 2017-09-24: +0.3 dB phase 134.0 list rank 242;
 2017-09-25: +2.2 dB phase 127.2 list rank 0;

All decoded an obviously correct message with uniform reference
phase, using the optimum list length for uniform phase;

Decoder memory for this one is 1.9 GByte when using optimum
list length of 325k for uniform phase search.  Not too bad.

Stacking all four gives Eb/N0 = +7.2 dB.

--
Paul Nicholson
--

<Prev in Thread] Current Thread [Next in Thread>