After some investigations by those using the Op system, General
consensus is ,
The posted image is not a Op transmission, for OP8 there should be a 8
second cyclic modulation with approx 50 % MK-SP ratio. or in the
case of OP32 32 seconds , the transmission should last 8 or 32
minutes.
The indicted stability would prevent a decode
The carrier placement routine seeks to place the carrier at the lowest
s/n point in the defined pass band , to prevent overlaying of
transmissions
If under direct VFO control, the operator is responsible for the
placement , noting that when operating at the lower levels , it may not
be possible to see or hear the signal's , this would not appear to be
the case in this instance.
As for spectrum efficiency, up to 4 and possibly more transmissions could
be fitted in the space occupied by the various frequency dependant
modes, so its most unlikely that conflicts will occur.
G..
--------------------------------------------------
From: "Alan Melia" <[email protected]>
Sent: Saturday, May 26, 2012 10:18 PM
To: <[email protected]>
Subject: LF: Re: Opera QRM picture
Hi Mike yes but it doesnt mean that digital mode ops dont need to listen
on
the frequency.....that old law of amateur radio :-))
Alan
G3NYK
----- Original Message -----
From: "Mike Dennison" <[email protected]>
To: <[email protected]>
Sent: Saturday, May 26, 2012 5:27 PM
Subject: LF: Opera QRM picture
Here is a picture of an Opera signal on 137.695kHz accidentally
QRMing my QSO with a very weak DR650BAR - his DFCW10 can be seen
sending the 'V'of 'XDV' and the 'B' of 'BAR' in DFCW before the QRM
starts.
Now, that's why we do bandplanning.
Mike, G3XDV
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