Return to KLUBNL.PL main page

rsgb_lf_group
[Top] [All Lists]

Re: LF: Re: more Wolf tests

To: [email protected]
Subject: Re: LF: Re: more Wolf tests
From: "John Currie" <[email protected]>
Date: Wed, 02 May 2001 04:11:00 -0700
References: <3AEFD6C6.26493.1590F2@localhost> <3AEFEEDB.6845.73A06A@localhost>
Reply-to: [email protected]
Sender: <[email protected]>
Hi all,  As you can probably tell from previous emails, I am not a fan of WOLF.
Basically I feel it simply takes a lot more spectrum space than it is worth. As 
I
stated earlier 60 to 80 QRSS stations can be received in the space taken up by 
one WOLF
transmitter. Now, even if  WOLF signals can be decoded at SNR 10 db worse than 
QRSS,
(which I dont believe has been demonstrated yet), that only means there could 
be 10
WOLF  QSOs for each QRSS QSO. With , However, 50 stations using using QRSS that 
means
there could be 5 times as many QRSS QSOs than WOLF QSOs for the same spectrum 
occupied.
It also means 5 times as many people can be enjoying their hobby.
        I wanted to add that I dont believe that really big openings last only 
a few
minutes. The biggest impediment to transatlantic QSOs is, in my opinion, CMEs 
and the
week after it takes the iononphere to go back to normal.  During times when 
condx were
not disturbed the signals from 300 mw stations were "O" copy for hours at a 
time.
Sometimes from 1/2 hour before my sunset to 0400 Z when I went to bed, the sigs 
were in
continuously.   Rapid QSB is evident during auroral activity and just after.
       For what its worth, I feel it is easier for me to copy CT1DRP than G 
stations.
Perhaps because there is less contact with the auroral zone on the VE1 to CT1 
path
      By all means I support the continuing testing of  WOLF . I am trying  to
visualise a future when 136 kHz is available on both sides of the Atlantic,  
when there
could be hundreds of stations trying to get across.  Two kHz aint much space
   73 de John VE1ZJ
Mike Dennison wrote:

ON7YD wrote:
> While WOLF is in an 'experimental stage' the carrier can be usefull for
> tuning purposes. But if you can detect a 2 or 3 second carrier, a DFCW QSO
> won't take more time than a WOLF QSO. So why make a simple thing difficult ?
> But wasn't it the (cl)aim that WOLF would be superior to primitive modes
> such as QRSS and DFCW ? If I remember well WOLF was given a 10dB credit
> over QRSS at 10 sec./dot, so assuming you want to copy a WOLF signal that
> is just 'at the edge' a 100 sec. carrier would be needed to make it visible 
with
> spectrogram-like software.

Hmmm. I was originally suspicious of that figure, and have seen nothing yet
that supports it. I am not aware of any amateur radio WOLF reception so far
that would not have been viable using QRSS, but the technique is at an early
stage.

I am still keen on WOLF on the promise that it can produce results from a
relatively short peak in conditions, whilst QRSS/DFCW needs a longer period
of enhancement. The really big peaks - the ones that would allow you, for
instance, to get through - last only a few minutes. Even if it is no better 
than 3s
dot DFCW, it may be an improvement in terms of time. This time factor was
identified this winter as the greatest barrier to regular two-way 
transcontinental
QSOs.

Also, I am not suggesting that the carrier should provide anything readable,
merely showing that a signal is there. This could be well down on an 'M'
QRS/DFCW transmission.

I remain skeptical but fascinated.

Mike, G3XDV (IO91VT)
http://www.lf.thersgb.net



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