From: "Dave Sergeant" <dave@davesergeant.com>
To: rsgb_lf_group@blacksheep.org
Date: Fri, 11 Sep 2009 07:23:46 +0100
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Subject: LF: Re: WOLF - ready to RX
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Thanks for the comments John and others.

Firstly of course Jim is VERY strong here, well over s9. I did try 
putting 30dB of attenuation in but he was still moving the meter...

I have not at the moment done the calibration. Both that and the small 
drift you see are complicated by my receive setup I use on 500kHz:

Datong UC1 upconverter feeding my K2 on 10m.

The Datong itself has a 116MHz downconverter crystal (144MHz to 10m) 
which is known to driift and hard to set precisely.

The K2, as most of you will know, is not a fully synthsised rig rather 
an analogue VFO locked to a coarser synthesiser in 10kHz steps. It is 
adequately stable for normal use but has a worse case 30Hz absolute 
error and a pretty small thermal drift (it doesn't have the frequency 
stability mod they did in later K2s).

Because of the difficulty of setting frequencies precisely things like 
'tune to 197kHz for a 1kHz tone' are meaningless - as I have to use the 
soundcard to check it is 1kHz..... you cannot calibrate that way, and 
neither can I do it on Loran since I have no AM mode.

So realistically this setup is not up to coping with these more exotic 
sound card modes which seem to assume you are using fully synthesised 
rigs. But it is just fine on other modes like RTTY and PSK - Wolf 
should be no different, it just sounds like slowish RTTY to me...

Back to normal modes I think...

73 Dave G3YMC

On 10 Sep 2009 at 17:45, John Andrews wrote:

> Dave,
> 
> On a quick look, I see some substantial frequency drift, probably due to
> the receiver, and also the possibility that your actual sound card
> sampling rate is quite different from the default 8000 Hz. Both of these
> things will keep the copy from building up, as the framing keeps
> changing.
> 
> Are you used to seeing frequency drift on QRSS signals? Do you suspect
> that the receiver isn't stable?
> 
> John, W1TAG
> 
> >> Well, easy for some (I can see) but NOT for me. What am I doing
> >> wrong?
> >>
> >> 19:19:11 >WOLF RESTARTED
> >> t:  24 f: 0.367 a:-0.5 dp: 85.8 ci: 1 cj:  0 1STCG6J2X7EUEWZ ?
> >> t:  48 f: 0.366 a:-0.4 dp: 85.7 ci: 2 cj:  0 VP*JV9IX47R60ZC ?
> > 
> > You are not alone Roger....
> > 
> > 2009-09-10 20:05:04 >WOLF10  -r 8000 -f 700 -t 10 -d 8 -w 0.0000
> > t:  24 f:-3.282 a: 0.2 dp:131.5 ci: 1 cj:202 Y 6NQSDZ42XVQHU ?
> > t:  48 f:-3.282 a: 0.2 dp:128.8 ci: 7 cj:252 XHW/EU864G09IUO ?
> > t:  96 f:-3.429 a: 0.1 dp:126.6 ci: 6 cj:472 SCE6XF5ZOGYP0IY -
> > t: 192 f:-3.477 pm: 8690 jm:456 q: -6.9 -8.0 HIQ*QAUZFJGT8XB ?
> > t: 288 f:-3.770 pm:11554 jm:455 q: -8.3 -7.8 K2WH67SKZF20??? ?
> > t: 384 f:-3.477 pm:11696 jm:455 q: -4.8 -4.9 M0BMU IO91VR 2W -
> > t: 480 f:-3.477 pm:13507 jm:455 q: -4.8 -5.7 M0BMU IO91VR 2W -
> > t: 576 f:-2.891 pm:20843 jm:453 q: -3.7 -8.0 0XB7VQ6W169B0J9 ?
> > t: 672 f:-2.891 pm:20855 jm:453 q: -3.5 -7.9 0XB7VQ6W169B0J9 ?
> > t: 768 f:-2.891 pm:20862 jm:453 q: -3.4-10.2 DGC1ALF5ZELF5HS ?
> > 
> > At least there are a couple of valid decodes there, but my quality
> > fields are way way below those of John's.
> > 
> > Like WSPR another of these toys which I will probably never look at
> > again...


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