On Fri, 24 Sep 2010 10:42:10 -0700
(Dave Platt) wrote:

Seems to me there's plenty of opportunity for flexibility with regards
to codecs. The protocol could be designed to allow for negotiation of
a common codec between two radios - start out with a simple
"universal" codec to get the communication started, and then
optionally switch to a different one.

Yes, that's what's wanted, but the current D-STAR implementation
appears to have no flexibility to do this and there are no version
fields in the frame structure so it can't be made backwards compatible.
The design ought to have had this built in, but seems not to have
considered doing it.

--

Brian Morrison

"Rob" wrote in message
...
Brian Morrison wrote:
On Fri, 24 Sep 2010 17:22:03 +0100
"Brian Reay" wrote:

Oh dear Rob, you must be new here! While what you say is, of course,
correct it isn't accepted by bigots.

I think you'll find that the only bigots involved here are the sort
that believe that amateur radio should encourage the use of closed
technology.

I think we should not encourage the use of closed technology, and I
think many agree with that.

But I also think we should not discourage developments (in the case of
D-STAR the development of a digital radio system) because in critical
places in the system open technology does not exist, and development
of such open technology is impractical.


Except digital voice doesn't work on noisy channels, which makes it pretty
useless for _REAL radio amateurs unless someone is going to stick repeaters
up every half mile. - that's gonna mean a lot of money to ICOM in my book
even if there was enough fools to fund it.

On 24/09/2010 18:02, Brian Reay wrote:
wrote in message
...
On 24/09/2010 17:22, Brian Reay wrote:

Amateur radio has many facets, DStar is simply one of them. Why can't
people
be left to enjoy their pet facets while others get on and enjoy theirs?


Because D-Star isn't amateur radio.

There is no experimentation involved, and can't be.

If the CODEC was open, or if the open CODEC ever comes to fruition, would
you have the knowledge / skills to undertake any meaningful experimentation
or even the remotest prospect of developing those skills?


Change the record Brian, you come out with the same paragraph every time
this subject comes up - and you know the answer you're going to get.

I don't have the skills, or even the time, to take part - but it doesn't
stop me from encouraging the project as a matter of principal. A closed
codec has no place in Amateur Radio.

You won't find more than a handful of amateurs who would disagree with
that (except, of course, the ones who have already bought a D-Star rig).

On 24/09/2010 18:08, Brian Reay wrote:
wrote in message
...

Remember packet. The AX.25 protocol was open, but it could not really be
changed because that would break compatability between the many
implementations that existed after some time.

Which is something the "anti" AMBE CODEC people ignore.

If the open CODEC happens, their scope to "experiment" with it will be
limited- unless they only want to talk to themselves or with others they've
co-ordinated experiments with.


In this case, you can always re-flash the chip containing your chosen
version of the codec.

Something very few had the capability to do back in the days when packet
was a big thing, and something you're expressely forbidden to do
(indeed, prevented from doing) with an AMBE DSP chip.

On 24/09/2010 18:10, Brian Reay wrote:
"Brian wrote in message
...

We
can't all do everything in amateur radio, but we should not prevent
those that want to do something in particular from being able to do it.

Exactly, so let those happy with DSTAR and the AMBE CODEC use it and enjoy
it.

You can do the same with your pet interests.

Win-Win.



I just hope the RSGB is as keen to licence Codec2 based repeaters as it
has been to licence D-Star based ones.

Or will the Codec2 team have to give the RSGB huge prizes for their
Radcom competitions to get the same treatment?

On 24/09/2010 19:24, Walt Davidson wrote:
On Fri, 24 Sep 2010 10:21:15 +0100, Brian
wrote:

On Thu, 23 Sep 2010 22:20:32 -0400
Mike wrote:

For what reasons would someone be "anti D-Star"?

D-STAR uses a proprietary codec, that means for anyone that doesn't
believe that amateur radio should use technology that forbids reverse
engineering and hence interoperability with homebrew designs it's
not acceptable.

It is rather curious, is it not, that it's often the same people who
are aggressively in favour of D-Star "because it is leading edge
technology", and yet are vociferous in their opposition to DAB
broadcasting "because it is no better than the existing analogue
systems".

Funny world.

73 de G3NYY


Interesting analogy (pardon the pun) Walt.

DAB doesn't work for mobile use.

Neither does D-Star.

On 24/09/2010 21:00, Yeti wrote:
On 24/09/2010 19:24, Walt Davidson wrote:
On Fri, 24 Sep 2010 10:21:15 +0100, Brian
wrote:

On Thu, 23 Sep 2010 22:20:32 -0400
Mike wrote:

For what reasons would someone be "anti D-Star"?

D-STAR uses a proprietary codec, that means for anyone that doesn't
believe that amateur radio should use technology that forbids reverse
engineering and hence interoperability with homebrew designs it's
not acceptable.

It is rather curious, is it not, that it's often the same people who
are aggressively in favour of D-Star "because it is leading edge
technology", and yet are vociferous in their opposition to DAB
broadcasting "because it is no better than the existing analogue
systems".

Funny world.

73 de G3NYY


Interesting analogy (pardon the pun) Walt.

DAB doesn't work for mobile use.

Neither does D-Star.

You'll be getting an email from you know who!

On 24/09/2010 21:01, Len GM0ONX wrote:
On 24/09/2010 21:00, Yeti wrote:
On 24/09/2010 19:24, Walt Davidson wrote:
On Fri, 24 Sep 2010 10:21:15 +0100, Brian
wrote:

On Thu, 23 Sep 2010 22:20:32 -0400
Mike wrote:

For what reasons would someone be "anti D-Star"?

D-STAR uses a proprietary codec, that means for anyone that doesn't
believe that amateur radio should use technology that forbids reverse
engineering and hence interoperability with homebrew designs it's
not acceptable.

It is rather curious, is it not, that it's often the same people who
are aggressively in favour of D-Star "because it is leading edge
technology", and yet are vociferous in their opposition to DAB
broadcasting "because it is no better than the existing analogue
systems".

Funny world.

73 de G3NYY


Interesting analogy (pardon the pun) Walt.

DAB doesn't work for mobile use.

Neither does D-Star.

You'll be getting an email from you know who!

They always make me laugh.

But I think he's given up now.

"Yeti" wrote in message
...
On 24/09/2010 21:01, Len GM0ONX wrote:
On 24/09/2010 21:00, Yeti wrote:
On 24/09/2010 19:24, Walt Davidson wrote:
On Fri, 24 Sep 2010 10:21:15 +0100, Brian
wrote:

On Thu, 23 Sep 2010 22:20:32 -0400
Mike wrote:

For what reasons would someone be "anti D-Star"?

D-STAR uses a proprietary codec, that means for anyone that doesn't
believe that amateur radio should use technology that forbids reverse
engineering and hence interoperability with homebrew designs it's
not acceptable.

It is rather curious, is it not, that it's often the same people who
are aggressively in favour of D-Star "because it is leading edge
technology", and yet are vociferous in their opposition to DAB
broadcasting "because it is no better than the existing analogue
systems".

Funny world.

73 de G3NYY


Interesting analogy (pardon the pun) Walt.

DAB doesn't work for mobile use.

Neither does D-Star.

You'll be getting an email from you know who!

They always make me laugh.

But I think he's given up now.

0ops ?....

In article ,
Brian Morrison wrote:

Seems to me there's plenty of opportunity for flexibility with regards
to codecs. The protocol could be designed to allow for negotiation of
a common codec between two radios - start out with a simple
"universal" codec to get the communication started, and then
optionally switch to a different one.

Yes, that's what's wanted, but the current D-STAR implementation
appears to have no flexibility to do this and there are no version
fields in the frame structure so it can't be made backwards compatible.
The design ought to have had this built in, but seems not to have
considered doing it.

I agree, that was a bad design choice. I always like to put
field-type and field-version tags into the data structures I use...
it's a bit more work up front but saves an incredible amount of pain
further along the line!

Anybody for "Free*Star"? :-)

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!