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Well yes that's true
There are other reason's as well , some data modes
are orientated , in that if the Tx sends
in usb , then the Rx must also be in
the same orientation usb , or vice versa ,
Modes have decoder bandwidths
that limit the amount of tolerance Tx/RTx may
accommodate , if multi Tx sessions are to be
decoded , then with simply the 'qrg' then
the Rx 'audience' are not sure if the
Tx will qsy out side there pass band
, eg , wspr (non hacked) is what 200 or 300
Hz wide , a well known ook
system uses two audio pass bands to
differentia speeds and another apparently
little used data system can
accommodate +/- 40 Hz in its MF version
and +/- 125 Hz in the HF/VHF version ,
Setting at the edge could result in lost decodes,
as most are now invisible ,
correct tx/rx alignment is vital and
yes as Mal would say , that's bottom
line for appliance operation , like
landing on instruments in the fog , everyone
has to have the same rule book .
Close by on 500 can mean upto 50
/60 miles as the ground wave seems
to travel very well , all that is yet to
come , when more users appear on 500 , south
of Watford-gap (traditional test of n/s
uk origin) there was Beacon-Bedlam when
the band first filled with qrss
stations effectively jamming each other on
rx ... happy days !
73 -G..
Sent: Sunday, November 18, 2012 5:13 PM
Subject: Re: LF: RXing JT9-2
Guess what Stefan meant is the center frequency of
his transmission, HF-wise.
And that's less ubiquitous than this
'dial'-thing, because the combination of the 'dial frequency' and 'audio
frequency' is irrelevant. Only the sum of both is relevant.
Example:
When
tuning to 136.0 kHz "dial" in USB on an analog HF transceiver, plus 1420 Hz
audio, the RX covers a range of 136300 to 139700 Hz (assuming the typical 300 to
2700 Hz pass). Assume there is a powerful transmitter near 139 kHz .. anyone
close to that transmitter (wink, wink..) will prefer to tune his RX to, for
example, 135.0 kHz "USB dial" and use 2420 Hz audio center frequency (assuming a
sufficiently configurable software).
Thus the center frequency of the real
transmission (137.42 kHz) is all one needs to know.
All the
best,
Wolf .
Am 18.11.2012 16:47, schrieb
Graham:
S,,
If jt9 is a multi tone (mfsk) system , as is
wspr , then which tone are you
declaring the frequency of ?
better to use the dial convention ,
Then everyone has the same (suppressed) carrier
frequency and what ever audio offset will be
unified
G) ..
Sent: Friday, November 16, 2012 9:50 PM
Subject: Re: LF: RXing JT9-2
Hi Mauro,
I'm on 137.42 kHz (i always tell the TX
frequency), yes JT9-2.
73, Stefan
Am 16.11.2012 22:42, schrieb
IK1WVQ Mauro:
Hi
Stefan,
are you trasmitting now ???
137 dial + xxxx
????
JT9-2 ????
I am trying to receive you
.
73
Mauro IK1WVQ
At 22.30 16/11/12,
you wrote:
Thanks Halldór!
Spiros,
did you decode the 21:08 and 21:12 transmissions? Is there someone else
watching?
73, Stefan/DK7FC
Am 16.11.2012 22:19, schrieb
Halldór:
Stefan,
Not very
consistent series from me. I am saving all if someone is
interested.
2100 4 -25
0.7 1423.0 0.00 DK7FC
JN49IK
2102 0 -31 0.3 1429.1
0.00
2104 3 -25 0.9 1423.0
0.00 DK7FC
JN49IK
2106 0 -32 -2.1 1421.1
0.00
2108 5 -23 1.1 1423.0
0.00
2110 0 -32 -1.3 1429.9
0.00
2112 4 -24 0.0 1423.0
0.00
73
Halldór
TF3HZ
From: [email protected] [ mailto:[email protected]] On
Behalf Of Stefan Schäfer
Sent: 16. nóvember 2012
20:53
To: [email protected]
Subject:
Re: LF: RXing JT9-2
Thanks Spiros,
That looks
consistent, you're loosing no single transmission.
The reports look
reasonable as well.
Tnx, 73, Stefan
Am 16.11.2012 21:47,
schrieb SV8CS- Spiros Chimarios:
JT9-2 on 136 Khz
·
2020 10 -14 0.5 1420.3 0.00 DK7FC JN49IK
·
2022 2 -36 -2.4 1370.0
0.00
·
2024 10 -21 0.4 1420.3 0.00 DK7FC JN49IK
·
2026 0 -39 2.4 1402.2
0.00
·
2028 10 -17 0.5 1420.3 0.00 DK7FC JN49IK
·
2030 0 -33 -0.6 1408.9
0.00
·
2032 10 -12 0.5 1420.3 0.00 DK7FC JN49IK
·
2034 1 -37 0.8 1426.8
0.00
·
2036 10 -10 0.3 1420.3 0.00 DK7FC JN49IK
·
2038 0 -35 -1.0 1436.5
0.00
·
2040 10 -16 0.4 1420.3 0.00 DK7FC JN49IK
·
2042 0 -30 0.1 1426.8
0.00
·
2044 10 -13 0.3 1420.3 0.00 DK7FC JN49IK
73,
Spiros
SV8CS
Nessun virus nel messaggio in
arrivo.
Controllato da AVG - www.avg.com
Versione:
9.0.930 / Database dei virus: 2441.1.1/5398 - Data di rilascio:
11/16/12 10:50:00
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