OK , It was simply a concept based on current systems , the original
panoramic digipan system capturing all, now expanded to cover rtty
and the Olivia recovery in drm780 , my experience with hf packet
back in the 80's when you could digi all over the place on 10 Mtr's ,
the wspr auto beacon
Improvements at layer 1 and at layer 2 would both be useful. If done
"right", both could be developed apart from each other. A better layer 1
protocol should work just fine with AX.25 as a data layer, or with some
improved "future" layer 2 implementation. Any improved layer 2 should work
fine wheth
Paul L Schmidt, K9PS wrote:
> I've got to agree with Jose here. AX.25 works pretty well on VHF,
> but falls apart on HF. But AX.25 is a link-layer protocol, not the
> whole suite of stuff that got crammed into a TNC. AX.25 may have
> been derived from the X.25 landline protocol, but using th
n
> Behalf Of Jose A. Amador
> Sent: Wednesday, August 06, 2008 1:54 PM
> To: digitalradio@yahoogroups.com
> Subject: Re: [digitalradio] Re: Has anyone looked into FPGA-based
> digitalmodes?
>
>
> What I feel is needed is something based on the established technology
> (AX.25, BBS Spec) with a new modem more suitable for HF than the old
> Bell 103 modem.
>
>
> 73,
>
> Jose, CO2JA
I've got to agree with Jose here. AX.25 works pretty well on VHF, but
falls apart on HF. But AX.25 is a link-layer protocol, not the whole
suite of stuff that got crammed into a TNC. AX.25 may have been derived
from the X.25 landline protocol, but using the obsolete landline modem
under it is th
Subject: Re: [digitalradio] Re: Has anyone looked into FPGA-based
digitalmodes?
What I feel is needed is something based on the established technology
(AX.25, BBS Spec) with a new modem more suitable for HF than the old
Bell 103 modem.
73,
Jose, CO2JA
Graham wrote:
> I really do not understand Graham's proposal: a narrow band spread
> spectrum system? I really need some more clarification about this.***
>
> Ok may be a bit like calling a steam train a iron horse, dose the
> same thing but a little differently
>
> Spread spectrum : ma
I really do not understand Graham's proposal: a narrow band spread
spectrum system? I really need some more clarification about this.***
Ok may be a bit like calling a steam train a iron horse, dose the
same thing but a little differently
Spread spectrum : may not be quite the intended
Sent: Tuesday, August 05, 2008 7:30 PM
> To: digitalradio@yahoogroups.com
> Subject: [digitalradio] Re: Has anyone looked into FPGA-based digitalmodes?
>
>
> Packet, Pax or ARQ FAE, at least to be able to share the frequency
> (collisions must be managed),
>
> Why not take the fi
Behalf Of Graham
Sent: Tuesday, August 05, 2008 7:30 PM
To: digitalradio@yahoogroups.com
Subject: [digitalradio] Re: Has anyone looked into FPGA-based digitalmodes?
>>>>>>>>>>
Packet, Pax or ARQ FAE, at least to be able to share the frequency
(collisions must be man
>>
Packet, Pax or ARQ FAE, at least to be able to share the frequency
(collisions must be managed),
>
Why not take the final step and code a narow band spread spectrum
packet system ..using very narrow bandwith short packet bursts based
on the ax25 system .enhanced by spread spre
There are multiple examples of reconfigurable devices that might prove
viable and not too costly. I am certainly not advocating against sound
card modes, or for high cost hardware. For me, hardware might prove
harder to get than software, but I just won't allow that fact to blind me.
Don't lo
Hello all,
For my small experience about ARQ modes, it seems to me that:
* a modern ARQ system does not really need a synchronous scheme as in Pactor
(with obligation to permanently exchange frames). It must be asynchronous as
Packet, Pax or ARQ FAE, at least to be able to share the frequency
Sometimes hardware is the right solution. I agree that it should be cheap
and open, but some things are more convenient in hardware.
A good generic hardware box containing a FPGA and some analog<--> digital
hardware can be just about *anything*, as long as the design allows for
arbitrary firmwares
$1000 modems are not going to be viable! Not if you want widespread usage.
Stick with open-source non-hardware based solutions.
Jeff -- KE7ACY
- Original Message -
From: Jose A. Amador
[snip]
Even when the soundcard seems the way to go, I would not discard a
priori a hardware sol
I have been playing with what has been available around, and the past
august, I devoted quite a bit of time to receive DRM. It is not easy,
in spite of the high powers the broadcasters use, and the more succesful
ones are the less greedy ones. I had far better results with RNZI and
its 17 kbp
Very good points, Jose,
Some of us had very high hopes for Q15X25 but never heard much about it
after it was tested, some years ago, even though some of us asked
repeatedly for information. It has taken a few years to hear bits and
pieces, but it seems that it just was not robust enough. I was
Message-
From: digitalradio@yahoogroups.com [mailto:[EMAIL PROTECTED] On
Behalf Of Jose A. Amador
Sent: Monday, August 04, 2008 11:10 PM
To: digitalradio@yahoogroups.com
Subject: Re: [digitalradio] Re: Has anyone looked into FPGA-based
digitalmodes?
Block codes and interleaving are used by many
; If there was anything actually better out there, the HF digital
> network would already be using it and AX25 Packet would only be found
> on the VHF/UHF bands.
>
> But there isn't, so...
>
> 73 DE Charles Brabham, N5PVL
>
> [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>
--- In digitalradio@yahoogroups.com, "Rick W." <[EMAIL PROTECTED]> wrote:
>
> ARQ modes don't necessarily have to be incapable of sharing a
frequency.
> Consider AX.25 packet radio, which has this capability.
>
I am speaking in practical, real-world terms rather than theories
about what could be
--- In digitalradio@yahoogroups.com, Howard Brown <[EMAIL PROTECTED]> wrote:
>
> Charles,
>
> What happened with Q15X25 ?? It looks promising, especially on VHF.
>
> Can you fill us in on how it worked or didn't work?
>
> Howard K5HB
You hit the nail on the head, Howard, about Q15x25 being es
ARQ modes don't necessarily have to be incapable of sharing a frequency.
Consider AX.25 packet radio, which has this capability.
Pactor does not necessarily have a particularly wide footprint. Both
Pactor and AX.25 packet are 2 tone FSK modes except packet is obviously
much wider due to the hig
4:16:46 PM
Subject: Re: [digitalradio] Re: Has anyone looked into FPGA-based digitalmodes?
PACTOR, being an ARQ mode is incapable of sharing a
frequency with more than one other station. That, along with the extreme
bandwidth and lack of effective signal detection makes PACTOR unsuitable for
digital
PM
To: digitalradio@yahoogroups.com
Subject: Re: [digitalradio] Re: Has anyone looked into FPGA-based
digitalmodes?
PACTOR, being an ARQ mode is incapable of sharing a frequency with more than
one other station. That, along with the extreme bandwidth and lack of
effective signal detection makes
At 04:16 PM 8/4/2008 -0500,Charles Brabham, N5PVL in part wrote:
>PACTOR, being an ARQ mode is incapable of sharing a frequency with more
>than one other station.
The same could be said about packet if it also was an ARQ mode such
as Pactor.
I understand that some are still PO'ed that their pa
rom: Jose A. Amador
To: digitalradio@yahoogroups.com
Sent: Sunday, August 03, 2008 9:16 PM
Subject: Re: [digitalradio] Re: Has anyone looked into FPGA-based
digitalmodes?
I believe that both the AX.25 and the BBS model are OK, but that the
packet channel coding is a disaster in t
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