Message-ID: <AC3B1FEE011A4FF781082DDA07637BD0@p4>
From: "Mark" <markhughes1@blueyonder.co.uk>
To: <rsgb_lf_group@blacksheep.org>
References: <fc7eccec0902201411l2ad41bdbo5350978f53f84c9f@mail.gmail.com>
Date: Sat, 21 Feb 2009 08:17:06 -0000
MIME-Version: 1.0
Subject: LF: Re: WSPR Spots
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Hi all,
The spurious calls generated here are as a result of a wideband birdie that 
wanders through the 500KHz band, probably a switchmode PSU
Not all the bad decodes get uploaded, so there would appear to be some 
filtering of what is uploaded
What the software needs is a checkbox after each decode, so that the user 
can mark bad messages, the system could them automatically remove those from 
the database

I have also been analysing the spots by graphing signal strength, and 
comparing for example my reception of SM5BHZ with that of other stations.
(for anyone interested I have used an Excel macro to download specified 
spots from the web database, and put them in a formal easy to use with the 
graph wizard)

I am coming to the conclusion that the single reported signal level is 
barely adequate on 500KHz, an pretty useless when the QSB is fast.. what 
WSPR software needs for studying propagation is perhaps 10 or 20  sig level 
measurements per period, just uploaded to the database for future study.  I 
have suggested this to Joe, but I think he has higher priorities and no-one 
else has requested anything similar

Regards
Mark GM4ISM
www.dc2light.co.uk


----- Original Message ----- 
From: "Andy Talbot" <andy.g4jnt@googlemail.com>
To: <rsgb_lf_group@blacksheep.org>
Sent: Friday, February 20, 2009 10:11 PM
Subject: LF: WSPR Spots


> According to the WSPR Spot database, there is some "interesting" DX
> being received chez GM4ISM.
> Is there some carrier or coherent  QRM present to generate these false 
> hits?
>
> Just got a WSPR generating routine running on a 16F628 PIC with AD9852
> DDS combination.
> At the moment it only operates at 100% duty cycle, but I'm Looking at
> PN sequences for randomised transmission slots with 20/25/33% Duty
> cycle operation.
>
> Andy  G4JNT
> www.g4jnt.com
>
>


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