I think in addition to one table per language you will also need
different tables for 75m than for 20m., hihi.
Leigh/WA5ZNU
On Fri, 13 Oct 2006 1:15 am, Rein Couperus wrote:
> I a working on such a scheme for PSKmail, with tables of 32k standard
> words (1 for each language),
Need a Digital mo
t/K5YFW
-Original Message-
From: digitalradio@yahoogroups.com [mailto:[EMAIL PROTECTED]
Sent: Wednesday, October 11, 2006 3:54 PM
To: digitalradio@yahoogroups.com
Subject: Re: [digitalradio] Re: Digital Voice: Some thoughts after one
week.
The one common theme I see with much of the digital
t: [digitalradio] Re: Digital Voice: Some thoughts after one week.
--- In digitalradio@yahoogroups.com, "DuBose Walt Civ AETC
CONS/LGCA" <[EMAIL PROTECTED]> wrote:
>
> I've heard DV using LCP-10 and a 16 tone modem as well as a 39
tone modem at 1200 bps...it sounds robot
Oops, I forgot about that 400 ms time segment! Yes, now I see what you
mean.
Thanks for helping clarify this.
73,
Rick, KV9U
cesco12342000 wrote:
>>From my understanding of the documentation for WinDRM, MELP
>>does work if the speed is at least 1,000 bps.
>>
>>
>
>No. 1000 bp400ms (bit
> From my understanding of the documentation for WinDRM, MELP
> does work if the speed is at least 1,000 bps.
No. 1000 bp400ms (bit per 400 ms) or 2400 bps
This per second / per 400 millisecond mixture is confusing !
Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org
Other
--- In digitalradio@yahoogroups.com, "Patrick Lindecker" <[EMAIL PROTECTED]>
wrote:
> I have listened some test in spanish with artificial voice reading
words. It was not too bad. The real problem is to translate voice in
symbols, in a reliable way.
>
Yes. There was that fairly recent QST articl
Glad that I was understanding that the 4-QAM was for the text part and
not voice. At least at this point of technology advancement.
Also, you had said earlier that:
"Tests with a 1200 bit/sec LPC codec have been negative (bad
intellegibility)."
From my understanding of the documentation for W
Hi Patrick and group,
I wonder if there would be much interest in this kind of DV? The main
argument was for having a high quality sounding voice in real time.
In the early 1980's, there used to be a product called HERO (Heath
Educational Robot) which allowed simple phoneme entry so that it co
> The only solution to do voice exchange with a low S/N would
> be to translate all the pronounced words in symbols
Exactly what i am thinking!
We need to establish a "phoneme alphabet".
Then, a correlator is needed to extract those phonems from the voice
input. Each phonem should have durat
> It was my understanding that the QAM-4 modulation was used for the
> text transmission
Negative.
Text and data can be anything from qam-4 to qam-64
FAC data (the callsign) is the only thing which is always qam-4
> and you needed to use at least QAM-16 for the
> voice.
Since the codecs use
006 10:54
PM
Subject: Re: [digitalradio] Re: Digital
Voice: Some thoughts after one week.
The one common theme I see with much of the digital modes that require
the higher level of speed is that the required minimum S/N ratio hovers
around 10 db S/N. It seems to be true with DV voice,
The one common theme I see with much of the digital modes that require
the higher level of speed is that the required minimum S/N ratio hovers
around 10 db S/N. It seems to be true with DV voice, with SCAMP, and
also with high baud rate modes (such as trying to exceed a few hundred
baud on HF).
--- In digitalradio@yahoogroups.com, "DuBose Walt Civ AETC
CONS/LGCA" <[EMAIL PROTECTED]> wrote:
>
> I've heard DV using LCP-10 and a 16 tone modem as well as a 39
tone modem at 1200 bps...it sounds robotic at best. But that could
have been just the systems used (ANDVT/Mil-STD-188-110)
>
> Wal
Sent: Wednesday, October 11, 2006 8:20 AM
To: digitalradio@yahoogroups.com
Subject: Re: [digitalradio] Re: Digital Voice: Some thoughts after one
week.
It was my understanding that the QAM-4 modulation was used for the text
transmission and you needed to use at least QAM-16 for the voice.
How man
igh-quality 2400-b/s digitized voice."
Walt/K5YFW
-Original Message-
From: digitalradio@yahoogroups.com [mailto:[EMAIL PROTECTED]
Sent: Wednesday, October 11, 2006 2:17 AM
To: digitalradio@yahoogroups.com
Subject: [digitalradio] Re: Digital Voice: Some thoughts after one week.
Some more in
It was my understanding that the QAM-4 modulation was used for the text
transmission and you needed to use at least QAM-16 for the voice.
How many bps can you get through with QAM-4?
If LPC doesn't work at 1200 bps, then what other codec do you suggest?
Even MELP (which is a type of LPC) normal
> The WinDRM specification is very sketchy ..
Well,... you are invited to provide a better one.
> but the FEC is not
> described. The interleaving of the pilots and overhead data is
> described but not the interleaving of the voice data.
It says "This document describes the DIFFERENCE of mod
Some more info:
I found a paper that describes some tests done with 2.4Kbps and
1.2kbps voice transmission over HF paths. It sounds like the 1.2
kbps gives useable voice quality.
I talked to a friend who had done some research for the military
back in the '80s on digital voice transmission ov
--- In digitalradio@yahoogroups.com, "Ed Hekman" <[EMAIL PROTECTED]> wrote:
>
> I found the specifications. The spec used for broadcast DRM can
be
> found here:
>
> http://webapp.etsi.org/exchangefolder/es_201980v020101p.pdf
>
> The WinDRM spec can be found here:
>
> http://www.qslnet.de/memb
It is not so much that the package is different between voice and text
modes, but rather, the amount of data flowing through the link in a
given amount of time. In order to have voice transmissions with good
intelligibility and no breaks in the signal, you need a VERY robust
data link. The Win
I found the specifications. The spec used for broadcast DRM can be
found here:
http://webapp.etsi.org/exchangefolder/es_201980v020101p.pdf
The WinDRM spec can be found here:
http://www.qslnet.de/member/hb9tlk/drm_h.html
Need a Digital mode QSO? Connect to Telnet://cluster.dynalias.org
--- In digitalradio@yahoogroups.com, Tony <[EMAIL PROTECTED]> wrote:
>
> Ed wrote:
>
> > Are there any communications engineers in this group that can
> > give us some idea whether a useable quality digitized voice can
be
> > sent over a 2.5 KHz wide HF channel with SNR comparable to or
less > t
kd4e wrote:
> I am puzzled as to why one digital signal works well under poor
> signal conditions and another does not.
You have to define "poor conditions" somehow.
It may be noise, multipath, ionospheric doppler, fading, etc. Each one
produces a different impairment, depending on the modulat
> Even though I am not an engineer, we know from P-25 that digital voice
> transmissions drop out before analog completely goes into the noise and
> it is my understanding that the narrowest BW they use is 6.25 KHz. And
> that is primarily for VHF/UHF frequencies that do not have the problems
>
Tony wrote:
> Ed wrote:
>
> > Are there any communications engineers in this group that can give
> > us some idea whether a useable quality digitized voice can be sent
> > over a 2.5 KHz wide HF channel with SNR comparable to or less >
> > than what is required for analog voice?
>
> I was thinki
Even though I am not an engineer, we know from P-25 that digital voice
transmissions drop out before analog completely goes into the noise and
it is my understanding that the narrowest BW they use is 6.25 KHz. And
that is primarily for VHF/UHF frequencies that do not have the problems
we have o
Ed wrote:
> Are there any communications engineers in this group that can
> give us some idea whether a useable quality digitized voice can be
> sent over a 2.5 KHz wide HF channel with SNR comparable to or less > than
> what is required for analog voice?
I was thinking about this today Ed. I'd
--- In digitalradio@yahoogroups.com, "Andrew O'Brien" <[EMAIL PROTECTED]>
wrote:
>
> I have been "QRV" on digital voice ,using WinDRM, and thought I
would offer
> some rookie/newbie random thoughts.
>
> 1. This mode's performance may appear counter-intuitive for most
digital
> mode operator
28 matches
Mail list logo