Jose,
Just as you were posting this message I was stumbling on a web site that
agreed with your comment.
With further searching I think I have the relationship. The QEX article has
the statement that to go from the 3kHz bandwidth used you subtract 34 dB
and add 10 log of the desired bandwidth in
For what it's worth Rud, PSK31 appears much more susceptible to phase
distortion that wider modes such as MFSK and OLIVIA.
Here, we are just over 50 degrees north latitude and have many more
occasions to experience the
Northern flutter from the aurora. This phase distortion knocks out PSK31
Of course it is. PSK31 goes raw, while MFSK and Olivia have FEC added.
So, stand a better chance of being decoded correctly.
When nature starts stirring the gas above, all it reflects (refracts)
suffers the same effect as it had passed thru the house of mirrors,
making giants look like dwarfs
Rud Merriam wrote:
Jose,
Just as you were posting this message I was stumbling on a web site that
agreed with your comment.
With further searching I think I have the relationship. The QEX article has
the statement that to go from the 3kHz bandwidth used you subtract 34 dB
and add 10 log
A friend just got his Navigator in the mail yesterday and is having
problems getting it to work. Anyone have any experience with the Navigator?
TNX 73,
Dave N0EOP
Hi Tony,
Too bad you did not also run MT-63 at all three
modes for comparison. I can tell you that next to
the various 75bps Robust mode on the
MIL-STD-188-110/STANAG modem, its very robust.
However under such conditions nothing but an ARQ protocol will really suffice.
/s/ Steve, N2CKH
At
Dave Sloan wrote:
A friend just got his Navigator in the mail yesterday and is having
problems getting it to work. Anyone have any experience with the
Navigator?
TNX 73, Dave N0EOP
It is slightly tricky to set up, but once you get it set up it works
wonderfully, and in a trouble-free
Up to PSK31, you can see this phenomenon. But if you increase the
speed (PSK63), you decrease the sensitivity to Doppler but also
increase (with 3 dB) the minimum S/N. All is a question of compromise.
Yes, my point was that adding convolutional encoder, coding gain could
somehow eliminate the
Hi Roger,
He worked with Glenn yesterday and Glenn is gone for the week-end. Of
course he doesn't want to wait. He says the interface shows he is keying and
the radio shows it is keying. But, he is getting nothing out. I told him to
try raising his ALC some and to also check the cable. It looks
Would the phase distortion that can corrupt a PSK signal occur the
same on a
M-PSK signal?
Phase and frequency modulation are two sides of the same coin. There
is a baseband transformation to translate from phase to frequency
modulation and vice versa - integration / derivation. Integrate
RTTY is binary FSK so the bandwidth is approximately the deviation (170 Hz)
plus the baud rate or 215 Hz.
73,
John
KD6OZH
- Original Message -
From: John Becker, WØJAB
To: digitalradio@yahoogroups.com
Sent: Saturday, October 27, 2007 01:04 UTC
Subject: Re: [digitalradio]
Dave Sloan wrote:
Hi Roger, He worked with Glenn yesterday and Glenn is gone for the
week-end. Of course he doesn't want to wait. He says the interface
shows he is keying and the radio shows it is keying. But, he is
getting nothing out. I told him to try raising his ALC some and to
also
Hi Steve,
Too bad you did not also run MT-63 at all three modes for comparison.
I did try MT63 at 2k, 1k and 500hz (squelch off). Copy was completely
garbled with the harsh path delay and frequency spread settings used. I
tried removing the AWGN noise channel from the simulator to see if it
Real attempts on 40 meters have had the same results for me.
On 20 it works far better, almost perfect..
MT63 is robust but too slow, and waving the carpet leaves it dizzy.
Being too slow, even slow doppler has a too high impact on it.
Jose, CO2JA
---
Tony escribió:
Hi Steve,
Too bad
Vojtech Bubnik escribió:
PSK as well as MFSK will be affected by multipath, it will create
another type of inter symbol interference - time overlap. DominoEX
with its incremental MFSK tries to cope with it, but there is a price
for that. I am not convinced yet that the incremental MFSK is
Have you found particular combinations of Olivia BW and tones that seem
to work the best for various conditions?
My frustration with Olivia is that it is impractically slow for keyboard
chats unless you use the higher baud speeds to get the wpm to at least
30 wpm. But then it does not seem to
Steve,
If MT-63 is robust relative to MIL-STD-188-110, then the latter may not
be all that robust! I do not find MT-63 to be all that robust, and it is
not as sensitive as other modes since it does not work well into the noise.
Do you have any real world amateur tests yet on the
Details K3UKXT2C2007-01-15 X40M RTTY7.038
BURKINA FASO
I don't seriously chase confirmation via cards any more, just QSL the
folks that send me theirs. Other than that, I rely on dribs and drabs
from LOTW. So today's XT2C card was quite a pleasant
Well, how about THAT. I'm glad you mentioned it, cuz I didn't even
notice the LoTW confirmation -- they must have just up loaded their
QSOs.
XT2C was very prompt sending out their hardcopy cards... I got min back
in April. First ever Burkina Faso for me, so it was a big deal.
But if I can get
Andy,
Congratulations, I also received four confirming band/modes including
the RTTY QSO, nice to see some DX Expo's using LOTW
Ron W4LDE
Andrew O'Brien wrote:
Details K3UKXT2C2007-01-15 X40M RTTY7.038
BURKINA FASO
I don't seriously chase confirmation
The part that I don't fully understand is the bandwidth calculation.
When I use PSK31, isn't the bandwidth pretty much set by the baud rate
and width of the signal? Often it is expressed as around double the baud
rate or ~ 60 Hz.
Now if I have my rig wide open with the 3.6 kHz bandwidth and
I took the dB results from the authors web page and calculated the bandwidth
adjusted dB and the Shannon-Hartley channel capacity:
Report
SNRBWBW Adj Adjusted Capacity
Mode (dB) (Hz) 10log(3k/b) SNR (dB) (bps)
SSB
Sorry but I may have missed something.
Your point is ? ? ?
At 07:11 PM 10/27/2007, you wrote:
I took the dB results from the authors web page and calculated the bandwidth
adjusted dB and the Shannon-Hartley channel capacity:
Report
SNRBWBW Adj
Hi Bonnie,
I've gone through the link below and unfortunately, haven't seen any
details on how to send SMS messages. Is there a step-by-step link I'm
missing?
tnx es 73
Bruce- W3NJ
--- In digitalradio@yahoogroups.com, expeditionradio
[EMAIL PROTECTED] wrote:
Cell Phone texting, also known
Hello Rick,
When I use PSK31, isn't the bandwidth pretty much set by the baud rate
The baud rate and the windowing (square, cosine...) chosen...
down to say 100 Hz, is this changing anything in terms of its practical
ability to work deeper into the noise?
There will be no change if you have
I think Patrick may be on to something here, ALE400 with ARQ FAE
worked very well in my QSO on 30M with Sholto KE7HPV. ALE without a
wide bandwidth !
GREETINGS TO ANDY FROM SHOLTO IN REPUBLIC, WA[23h51m29s] [AMD] [from
KE7HPV ] [to K3UK] (his BER=30 + SINAD= 7)
ok we got a connect
Done.
On 10/23/07, Mike Miller [EMAIL PROTECTED] wrote:
Hi Andy,
Please add me to the list. I'm not real active, but maybe that will
change. The call is KC9DOA.
Thanks,
Mike
*Andrew O'Brien [EMAIL PROTECTED]* wrote:
It took a while, but I have mined the information associated
Agree,
After several ARQ FAE qsos and some via unproto, the ALE400 mode does
surprisingly well both on the lower and higher bands...well worth
further investigation.
73,
Bill N9DSJ
--- In digitalradio@yahoogroups.com, Andrew O'Brien
[EMAIL PROTECTED] wrote:
I think Patrick may be on to
This is to address the question of why a mode can work at -10 dB when
Shannon-Hartley indicates this is not possible for that mode. The
calculations adjust the reported dB for a 3kHz signal to the show the dB for
bandwidth of the mode. This is the dB applicable for Shannon-Hartley.
I lacked the
I don't think 10% of each HF ham band is at all
reasonable. Perhaps 10% of each data b
and segment would be more reasonable. Your suggestion for automatic
sub bands would take an unreasonably large part of most data sub bands.
see my notes below in [brackets]]
73,
Chuck Mayfield - AA5J
But
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