schrieb Stefan, :)
Why do you think so?
Its linked to the DSP engine in Op , there is a timing issue , if
other applications lock the sound card at a different rate , due to
the % tolerances , low level decodes can be lost , noting, Op is a
'data mode , so the overheads in the transmission are much higher ,
as are the DSP engine requirements , as can be seen with 'older' pc's
cpu loading can be a issue , as is a one-pass system , all the
processing is taking place in real time
But on with the show ,
73 -G..
-76 dB in 28 mHz b/w , what is that when translated to 2.5Khz
B/w ?
--------------------------------------------------
From: "Stefan Schäfer" <[email protected]>
Sent: Wednesday, July 25, 2012 3:08 PM
To: <[email protected]>
Subject: Re: LF: 4X OP32 report
Am 25.07.2012 15:51, schrieb Graham:
Pity nothing decoded in the US last night , but signal 's in 1500
/2000 mile range where quite substantial ...
from this , it seems that propagation on 136 is really linked to the
seasons ?
Yes (of course) and no. W1VD received me quite well a few weeks ago, see
https://dl.dropbox.com/u/19882028/LF/07_July2012.jpg
Not to forget W1TAG:
https://dl.dropbox.com/u/19882028/LF/DK7FC_Juli2012.jpg
So there is some propagation in summer but of course it depends on the
solar activity. Don't know how the condx have been yesterday.
One point from previous trials , If Spec-lab is used with Opera
, then SL must be set to 48Khz sample rate , or OP can loose low
level decode sensitivity.
Why do you think so? As long as the frequency range of a SSB bandwidth at
audio levels passes through the SL filter, then it should be fine. So 8
kHz SR should be fine. Of course it depends on which shift frequency you
have to use. I have to use 11 kHz shift and so i choosed a SR of 30 kHz.
73, Stefan
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