Message-ID: <000901c0b4a4$cc589ed0$687a37c0@w2ksn>
From: "Stewart Nelson" <sn@scgroup.com>
To: rsgb_lf_group@blacksheep.org
References: <3.0.5.32.20010322142117.0083bc10@pop3.esoterica.pt> <14gsjv-0BYKP2C@fwd07.sul.t-online.com>
Subject: LF: Re: wolf and inputpwr
Date: Sat, 24 Mar 2001 12:55:45 -0800
Organization: SC Group
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Hi Uwe and all,

The present implementation of WOLF, unfortunately, has very poor
dynamic range.  The BPSK signal must be between -20 dB and -50 dB,
relative to full scale.

If you are receiving your own transmission, or one from a nearby
station, you may need to reduce the record level by 20 dB to prevent
internal overload when it starts averaging.

If you are trying to receive a signal buried in noise, you should
set the record level so that frequent peaks reach -6 dB or higher,
even if it means that occasional static crashes overload.
This will ensure that the -50 dB minimum is not a limiting factor.

If your Rx output is dominated by a strong interfering carrier, it may
not be possible to set the record level high enough.  In this case,
try to reduce the interference with a narrower IF filter, with a notch
filter, or by preprocessing the recording through an audio editor
with filtering features.

Although 8-bit recordings normally degrade the effective S/N only
slightly, recording in 16 bits can be a big help if the signal is
mostly QRM, rather than noise.

You will have to live with the dynamic range limitations for quite
a while, because my priorities are for improving usability and weak
signal performance.  Sorry for the trouble it has caused.

73,

Stewart KK7KA

----- Original Message -----
From: "jannsen" <0482183881-0001@t-online.de>
To: <rsgb_lf_group@blacksheep.org>
Sent: Saturday, March 24, 2001 10:26 AM
Subject: LF: wolf and inputpwr


> Hi all WOLFers,
> I am in the believe WOLF decodes vy weak signals. but with my equipment it
> decodes only if dp: is higher than abt 32. seems Brians line (down on the
page)
> proves that for true.
> what is wrong with my believe ?
>
> WOLF version 0.52
> t:  24 f:-0.646 a: 0.5 dp: -4.9 ci: 0 cj:302 ??????????????? -
> t:  48 f: 0.356 a: 0.4 dp: -9.0 ci: 0 cj:302 ??????????????? -
>
> t:  24 f: 0.356 a: 0.4 dp: -5.0 ci: 7 cj:384 ??????????????? -
> t:  48 f: 0.355 a: 0.5 dp: -9.2 ci: 7 cj:277 ??????????????? -
>
> t:  24 f:-0.646 a: 0.5 dp: -5.2 ci: 0 cj:302 ??????????????? -
> t:  48 f: 0.351 a: 0.8 dp:-10.3 ci: 6 cj:297 ??????????????? -
>
> t:  24 f:-0.001 a: 0.5 dp: 20.4 ci:13 cj:136 ????????????/O* -
> t:  48 f:-0.001 a: 0.5 dp: 19.6 ci: 6 cj: 91 Q94???????????? ?
>
> t:  24 f: 0.000 a:-0.6 dp: 31.7 ci:12 cj: 63 31O3Z4053???3OW ?
> t:  48 f: 0.001 a:-0.7 dp: 26.0 ci:12 cj: 63 3TNU1O053???3OW ?
>
> t:  24 f: 0.000 a:-0.0 dp: 33.4 ci:14 cj:104 RFJ*TV8*K/1KRH* ?
> t:  48 f: 0.000 a:-0.0 dp: 29.3 ci:11 cj:145 G.4YPJQIFDV*2.W ?
>
> a line from Brian:
> t:  24 f: 0.001 a:-1.2 dp: 79.9 ci: 9 cj: 44 CQ M0BMU M0BMU  -
>
> t:  24 f: 0.000 a: 1.4 dp:139.3 ci: 0 cj:373 531531531531531 -
> t:  48 f: 0.000 a: 1.4 dp:135.2 ci:10 cj:427 K*4/USY0JZLB9P/ ?
>
> regards
> Uwe/dj8wx