"Paul Keinanen" wrote in message
...
On Fri, 28 Nov 2003 03:26:01 GMT, "charlesb"
wrote:

Recently I have heard references from multiple sources about 9.6kb PSK
activity on HF bands.

I assume this refers to 9600 bit/s.


What's the deal on this? Is it a wide, multi-stream mode like Q15x25
mode?

It sounds illegal, but lots of things sound illegal if you are not
familiar
with the facts. That's me...

A 9600 bit/s QPSK signal fits nicely within the same bandwidth
occupied by an AM phone transmission, with 8PSK (or 8QAM) the signal
would fit into the bandwidth of SSB phone transmissions. If the
bandwidth limit allows AM or SSB, then what is the problem with other
modes with similar bandwidths ?


Well except that for standard PSK enthusiasts tout it's exceptionally narrow
bandwidth thus allowing more conversations in a given space than even CW.
What point is there in creating a wide digital mode?

Dee D. Flint, N8UZE

"Dee D. Flint" wrote

Well except that for standard PSK enthusiasts tout it's exceptionally narrow
bandwidth thus allowing more conversations in a given space than even CW.
What point is there in creating a wide digital mode?

Dee D. Flint, N8UZE

Single channel PSK has nothing in common with high bandwidth information
transport. What one group touts may be exactly opposite of what another
group touts. Sometimes 31 bps at 31 baud is good enough, other times
3600 bps at 50 baud is what is needed.

The point in creating a wide digital mode, is to increase throughput per second.

"Dee D. Flint" wrote in message
gy.com...

What point is there in creating a wide digital mode?

More throughput, error correction for 100% copy, ability to transfer binary
files. ( Q15x25 guys like to send JPEG's back 'n forth, kind of like SSTV,
except the pics come through 100% good. )

Obviously any wide mode is overkill for keyboard QSO's, but there's a whole
world of other things that hams want or need to do, and some of them require
more bandwidth.

There are a lot of pro's and cons related to utilizing the wide modes for
any purpose. I don't think we will have to worry about them becoming so
popular that they will squeeze out everybody else.

Charles Brabham, N5PVL
Director: USPacket.Net
http://www.uspacket.net

"charlesb" wrote in message
. com...
More throughput, error correction for 100% copy, ability to transfer
binary
files. ( Q15x25 guys like to send JPEG's back 'n forth, kind of like SSTV,
except the pics come through 100% good. )


Charles Brabham, N5PVL
Director: USPacket.Net
http://www.uspacket.net


Where are the Q15x25 QSOs going on. I have MixW, which should work this
mode, but I am not aware of ever hearing it on the HF bands. Is this a
VHF/UHF only mode?

73 - Mike - K9JRI

"Mike Blake" wrote in message
gy.com...

Where are the Q15x25 QSOs going on. I have MixW, which should work this
mode, but I am not aware of ever hearing it on the HF bands. Is this a
VHF/UHF only mode?


It's intended for HF, but works great on VHF/UHF too. Operating freqs listed
in the pages that follow.


http://home.att.net/~ronchap/q15x25modes/q15x25.htm

http://sharon.pi8zaa.ampr.org/mirror...25/Q15X25.html

There is also a Yahoo group named "Q15x25" that is a great source of info on
operating this digital mode.

Briefly: Q15x25 uses 15 PSK streams at 88.xxx baud each, theoretically
giving you around 2500 baud. That's where the 15 and 25 in the name come
from. It butts right up against the legal limits of bandwidth, but doesn't
cross those limits and is so it legal, despite doubts that some have
expressed in the past.

Q15x25 operates exactly like packet. It's a connected mode, and if a frame
gets through at all, it gets through intact. From what I can tell, the most
popular activity among Q15x25 enthusiasts is to swap JPEG images on the air,
kind of like SSTV but with error-correction so the pics always come through
clean.

There are versions for Linux and Winders.

My on the air experience with Q15x25 is that it works great when you have
clear spectrum, but under noisy conditions is no better or worse than 300
baud packet! - Except of course it takes up several times as much spectrum
to do so. Q15x25 will not pull out weak signals you can't hear or any of
that kind of stuff. On the other hand, under decent operating conditions it
can be pretty fast.

I also have discovered that by boosting the TXD up to 800-1000 MS or more,
you can conduct Q15x25 QSO's over a normal VHF voice repeater. A nice 2500
baud data transfer system for emergency use anywhere there is a voice
repeater... Admittedly not ideal, but still a big step up from nothing.

I remember reading a few weeks back that the author/authors of Q15x25 were
currently working on a new version, so it appears the mode is alive and
well, if not popular due to it's width. It really is hard to find a good
place to operate Q15x25 on busy freqs.

That's the problem with the wide modes, I guess. TANSTAAFL

Charles Brabham, N5PVL
Director: USPacket.Net
http://www.uspacket.net

"Mike Blake" wrote in message
gy.com...

Where are the Q15x25 QSOs going on. I have MixW, which should work this
mode, but I am not aware of ever hearing it on the HF bands. Is this a
VHF/UHF only mode?


It's intended for HF, but works great on VHF/UHF too. Operating freqs listed
in the pages that follow.


http://home.att.net/~ronchap/q15x25modes/q15x25.htm

http://sharon.pi8zaa.ampr.org/mirror...25/Q15X25.html

There is also a Yahoo group named "Q15x25" that is a great source of info on
operating this digital mode.

Briefly: Q15x25 uses 15 PSK streams at 88.xxx baud each, theoretically
giving you around 2500 baud. That's where the 15 and 25 in the name come
from. It butts right up against the legal limits of bandwidth, but doesn't
cross those limits and is so it legal, despite doubts that some have
expressed in the past.

Q15x25 operates exactly like packet. It's a connected mode, and if a frame
gets through at all, it gets through intact. From what I can tell, the most
popular activity among Q15x25 enthusiasts is to swap JPEG images on the air,
kind of like SSTV but with error-correction so the pics always come through
clean.

There are versions for Linux and Winders.

My on the air experience with Q15x25 is that it works great when you have
clear spectrum, but under noisy conditions is no better or worse than 300
baud packet! - Except of course it takes up several times as much spectrum
to do so. Q15x25 will not pull out weak signals you can't hear or any of
that kind of stuff. On the other hand, under decent operating conditions it
can be pretty fast.

I also have discovered that by boosting the TXD up to 800-1000 MS or more,
you can conduct Q15x25 QSO's over a normal VHF voice repeater. A nice 2500
baud data transfer system for emergency use anywhere there is a voice
repeater... Admittedly not ideal, but still a big step up from nothing.

I remember reading a few weeks back that the author/authors of Q15x25 were
currently working on a new version, so it appears the mode is alive and
well, if not popular due to it's width. It really is hard to find a good
place to operate Q15x25 on busy freqs.

That's the problem with the wide modes, I guess. TANSTAAFL

Charles Brabham, N5PVL
Director: USPacket.Net
http://www.uspacket.net

G'day Guys!

Came across your thread and just thought I would give you all some great news about Q15X25!

Currently there is finally firmware being developed for the Kam XL Dual port DSP TNC range!.

This is great news for those who don't wish to rely on PC / Sound Card hardware to run this mode, finally there will be a small black box solution!.

Regards,
Ken.
VK4AKP.
.-.-.

VK4AKP writes:
Currently there is finally firmware being developed for the Kam XL Dual
port DSP TNC range!.

This is great news for those who don't wish to rely on PC / Sound Card
hardware to run this mode, finally there will be a small black box
solution!.

Cool. I wonder why nobody builds this stuff directly into radio
tranceivers.

What I really want is a portable PSK31 tranceiver with an alphanumeric
keypad, 4 line (or so) LCD text display, AA battery pack, all the
PSK31 modulation/demodulation stuff, and all the RF stuff in a single
box, no computer needed. I'm imagining something about the size of an
FT817 and reasonably rugged. It could be single band, like 20 meters,
and it would of course have a computer port for when a computer was
available. That would be a way to have fairly reliable DX portable
communications without resorting to satellites.

I wonder why nobody makes anything like this, or builds the feature
into FT817-class radios. I'm sure there'd be demand for it.

In article ,
Paul Rubin wrote:

Cool. I wonder why nobody builds this stuff directly into radio
tranceivers.

For one thing, the market for digital modes is so small compared with
the market for voice operation. For another, the digital modes keep
evolving rapidly, so it's a lot easier to use a PC to develop and
distribute software than having it in some form that only works in a
particular make and model transceiver.

Seems like the transceiver makers are just now getting around to having
the higher-end models able to decode and display RTTY. That isn't a
feature I would pay for, because I do lots of digital modes, and because
I would imagine those that run in a PC might do a better job of decoding
than something built into the transceiver. The PC software gets lots
of user experience and frequent updates until it is more or less
optimized. You don't get that with something built into the transceiver.

Not to say that you don't have a legitimate wish for a highly portable
PSK station. Just that it is unlikely to happen in a commercial product.
--

jhhaynes at earthlink dot net

Hi Ken,
As soon as they have that Firmware available I will be getting one...
Have been playing with MixW and Q15x25.... Nice....

I do like the TNc idea as well..


73 jerry n9lya
"VK4AKP" wrote in message
...

G'day Guys!

Came across your thread and just thought I would give you all some
great news about Q15X25!

Currently there is finally firmware being developed for the Kam XL Dual
port DSP TNC range!.

This is great news for those who don't wish to rely on PC / Sound Card
hardware to run this mode, finally there will be a small black box
solution!.

Regards,
Ken.
VK4AKP.
-.-.


--
VK4AKP