Confused about Digital Modes

[VK2CSW]

I have done some reading, honest injun.

The more I look the less interested I become.

Modes like WSPR do not interest me as they are "autonomous" to a great degree and I am not in a position to make use of any of the 'research' data it may glean.

Most of the modes seem, to me at least, to be archaically slow in their throughput rates - 10's or 100's of bps is the stuff of the 1970's and of little practical use.

So guru's, I ask for guidance.

Is there a digital mode, that is in use and is of some practical uses?

Given that AR is supposed to be innovative, and forward looking and that data is the future where can I go to learn about useful data modes?

(Please don't derail the thread extolling the virtues of your favourite mode if it is one of the slow ones - I am asking for info on modern and fast modes. Thanks)

[VK3ALB]

Hi Colin,

Considering in most cases digital modes in AR (in my view) are only used to complete a contact there's not a lot of need for high speed comms. I read something in the early days of D-star that there was a 128k data channel but never found out any more about it. I guess a 128k peer to peer link could be of some use.

What do you consider fast and what is your application?

edit

A quick look on Google found this amongst other thing:

http://www.dstarinfo.com/Data/Sites/1/S ... eddata.pdf

[VK3AIF]

There are digital modes for most everything out there but which suits depends very much what you expect to use it for, the real slow ones are optimised for weak and I mean weak signal work. If you wish to exchange data on VHF or above with good signal strengths try AX-25 but that is no world beater in the data rates because of the bandwidth limitations imposed by the LCDs. If it is HF you want try AMTOR, PACTOR or RTTY but again that is no world beater in the data rates because of the bandwidth limitations imposed by the LCDs either.

Have a bit of a read of this link http://vkfaq.ampr.org/specdigitalhf.php and if it is not what you seek, keep searching there will most likely be something somewhere.

73

[VK4WDM]

Hi Colin

I was a digimode skeptic too but I was really struggling to get many contacts at all given my very limited antennas at this QTH and loss of hearing that impeded my cw and phone skills. Then I discovered digital modes, in particular JT65 and PSK, and I having the best fun in years. I am making contacts all over the world using a simple vertical, or end-fed wire, and 30 watts.

After only four months I am well on the way to DXCC on JT65 and have only four states to go for Worked all USA states. No, they are not super quick, but are very efficient - I can easily work stations on 40m that are buried under QRN that would be impossible with CW or SSB.

The downside is that they are a but impersonable but so are many of the CW contacts these days: "UR 599, TU, RR, 73."

Why not give some digimodes a try? Most of the programs are free, all you need is an interface of some sort and a basic computer. If you don't like them, nothing is lost. I you don't try, you will never know!

73

Wayne VK4WDM

[VK2XSO]

As mentioned above, it does really depend on what you want to do as to which mode you use.
CW as mentioned is a personal hand made mode Run morse with a computer and some of the hand operators can get the feeling they're talking to a teleprompter.

WSPR, PSK31 etc are weak signal modes. The point isn't speed, it's the ability to communicate where normally you could not.

In the case of AX.25 type modes which have more practical uses. While the packet BBS network is now mostly gone because of internet it has found other interesting uses with
APRS. So much so that the APRS network is now bigger than the BBS/ROSE/NETROM/TCPIP network ever was. All because somebody decided to do something different with it.

DSTAR as mentioned has 128kbps capability. Packet radio never went much past 9600bps, though some stations made it to 56k.

I thought that 802.11 may have been adopted by the amateur radio community and icom even made some cards to do the job on 2.4GHz in the early days.
Hams didn't take it up and Icom or other manufacturers didn't consider trying 802.11 on bands like 70cm or 23cm with higher power like 5W.

For high speed data, 802.11 or 802.16 specifically on ham bands might kick off, but it requires somebody beyond my skill level to develop it.

The last option is to modify some commercial units like microwave units.
AWA made some RMD800 (800MHz) and RMD1500 (1500MHz) units and a lot of these have gone to scrap. These units are capable of being modified to 23cm.
The manuals with circuit diagrams are often thrown out with them. They're capable of 2 x 2MBps
Trio make some 920MHz units for the ISM band, it would be nice if we had a 920Mz band.
LEDR make some 400MHz and 1500MHz that can do 4 x 2MBps or 10MBps ethernet.
And then there are no shortage of old NEC pasolinks for 10GHz, 11GHz, 18GHz, 47GHz. Most of these are capable of 4 or 8 x 2MBps E1's.

These ex-commercial microwave links might seem to be useless, but it really comes down to putting them to use. If you don't have a use, find one.
Our club currently has a 10GHz microwave link I recovered and modified. We're installing it to link two repeaters over 50km and provide enough bandwidth for
video cameras and an ethernet link.
We'd link a lot more sites if we could get a hands on more ex microwave links. It's slow going but we're making sure they don't end up in the scrap metal bin.

And still we support the most number of digipeaters in Australia running a puny 1200bps.
Our new goal is to top the gateway erlang charts

[VK4WDM]

Run morse with a computer

Easy on Trash! You will have the trad CW ops having a stroke with such an outrageous suggestion

73

Wayne VK4WDM

(and CW ops, this IS an attempt at humour).

[VK2FAK]

Hi all....

First you need to define your requirements, and then basically how fast can you type, there are some modes I can't keep up with and I wont use the macros. I only use the macros for the basic repeatable stuff callsigns and such, never in the body of the chat....

I am always surprised why there is not more people using Olivia....comfortable typing speed and good weak signal ability....

John

[VK4WDM]

why there is not more people using Olivia

I have been trying to get an Olivia contact for about 18 mths without success. Typing speed is an issue with me which is why I like JT65 which almost all macros.

73

Wayne VK4WDM

[VK2HRX]

WICEN in NSW has been running digital nets very regularly for the last 9+ months on HF as well as VHF. Olivia is a frequently used mode on HF. Feel free to join in. Go to the WICEN NSW web site and on the rhs you will see the details of the next one.

[VK2FAK]

Hi all....

Wayne..

Do you look at HamSpots....you may be able to find someone on air the same time as you and get the Freq. right......its not easy..

Looking at HamSpots, there has been a few people on in the last Hour or so.......looking for Aussies I think you can forget that.....

Check in the afternoon up around 14.108 or there abouts, usually some using 1000/32 Olivia a couple out of Europe and Local Islands...

John

[VK4WDM]

Hi John

Hamspots. Good idea!

Colin, just looking at the JT65 decodes on 15m and 20m. Stations from Europe, North America, Africa and Asia all lining up to be worked on 30w and a bit of wire

Have not checked PSK yet but it will be much the same.

73

Wayne VK4WDM

[VK2FAK]

HI all....

Don't want to hijack that thread........Wayne...you have been a busy boy looking at your History on Hamspots ....


And speed of transmission is going to have a big effect on the distance , and weak signal ability of the transmission......so I guess you have to make a decision ..
You will notice all the modes that have very good weak signal ability are very slow...and limited in what you can send......If you just want a local digital mode...then almost any of the fast ones will do,,,,you just have to find locals using it...

John

[VK2CSW]

Hi All and thanks for the replies,

I really don't have an application in mind - other than "self education" and "having a play".

It just seems a little odd that in a time where data is all important no-one in the hobby is really showing progress (that I have found) to provide useful data rates.

It seems to me that groups like WICEN, AREC, ARRL etc would need to provide back up data services to ESO's during times of duress - I can't see it being an optional service but required in today's connected world.

I will extract the digit and take Compton's advice and at least have a listen to the WICEN OLIVIA nets - as a starting point.

I guess there is nothing for it but to start digging deeper and actually get some software, oh and finally put a computer of some sort in the shack
(You wouldn't think I've worked in IT for most of my life...)

Thanks Again

[VK3ALB]

It's clear from most of the replies that amateurs think of digital modes in terms of making and completing contacts, an application that needs little bandwidth/speed. Nothing wrong with that. It's that all important application requirement that drives the need for speed. Trash's use of data links to push video around demonstrates that. I don't think AR has yet worked out how to harness high speed links (MB/s or GB/s) in any practical way. Seems like a frontier waiting to be explored.

[VK3YE]

I don't think AR has yet worked out how to harness high speed links (MB/s or GB/s) in any practical way. Seems like a frontier waiting to be explored.

Good point Lou.

If ever we were to get all of 50 - 54 MHz back, imagine the benefits if we used all 4 MHz exclusively for medium speed wireless broadband data.

As a bonus it would end all the squabbles over 50.110 MHz and be hamdom's contribution to World Peace.

[VK2LK]

Good call Peter!

Its perfect for someone well versed in Software Radio techniques to come up with a nice wideband multiple carrier OFDM based protocol that could squeeze high data rates over the air (much the same as microwave and cellular stuff does already)

These babies can do 25MHz bandwidth Tx and Rx or up to 50Mhz if you're willing to trade some resolution for bandwidth and put it in 8 bit mode --> https://www.ettus.com/product/details/UN210-KIT

Sadly I doubt too many people on here understand what I'm talking about, and even fewer are capable of implementing it (me included)

Cheers,
Matt

[VK4WDM]

If ever we were to get all of 50 - 54 MHz back, imagine the benefits if we used all 4 MHz exclusively for medium speed wireless broadband data.it would end all the squabbles over 50.110 MHz

No Peter, I won't bite, I won't. Tongue firmly between teeth and anal muscles tightly compressed

Wayne VK4WDM

[VK2FAK]

Hi All....

The basic idea of any amateur transmission , in my opinion is to communicate with someone a long distance away.....so thats the reason all of these weak signal modes have come to light over a number of years....also the use of low power to operate them....

For something to be developed there needs to be a use in mind for it......In this part of the forum we had a new section about amateur TV.....there is little if any activity in that thread, does this reflect the interest in it....maybe....on this forum anyways.


So you want some high speed data modes.....for what purpose....at this point in time I have no need for high speed on air data, does any amateur ?.....a software developer is not going to waste his/her time if there is not going to be the possibility of wide appeal for the software, even for a short time..


John

[VK3BSF]

Sadly I doubt too many people on here understand what I'm talking about, and even fewer are capable of implementing it (me included)

Cheers,
Matt

If u gonna talk the talk then u gotta walk the walk

[VK4WDM]

I have to agree with John

A lot of work has gone into the development of existing digi-modes - just look at the number that are available in programs like FLDIGI (my favourite) and Ham Radio Delux (both free) or MIXW, yet most of these modes seem to get little widespread use, and some are only used by a small number of dedicated enthusiasts. This is not due to any difficulty in setting them up - once you have got an interface, installed the software, and set up your radio, all can be used with a mouse click.

So the question is the lack of use due to their slow speed? No. The two most popular modes in use atm are JT65 and PSK. Neither of these are fast. They are popular because of their weak signal effectiveness. JT9 is the new kid on the block and is gaining popularity. Apparently there are also other modes in the pipeline that will be even more effective for weak signals, but they will not be high speed.

So, as John says, what would the developement of high speed digimodes add to AR? (Apart from meteor scatter which already has a fast mode- FSK441).

And let's not forget about Colin - just jump in and have a play with the existing modes. You can build your own interface, but there are good bargains on second-hand ones such as those from Rigblaster or Signalink (the best IMHO). But be warned, those "tweedly-dee" sounds are very seductive and you are in danger of getting a serious addiction!

73

Wayne VK4WDM