Ham / SSB Cruisers Nets with PSK31 ?

[msponer]

Has there been any thought to use PSK31 for cruisers nets?

My vision is a text based 'chat room' style cruisers net through HF.

The advantages are:
- PSK31 works with a normal PC sound card, so no expensive modem is needed, it even works on tablet computers and smart phones with an easy to make adapter cable.
- PSK31 has much better range than voice SSB and works with more marginal HF propogation
- Faster and easier to communicate numbers for check ins and weather
- Could automate checkins from NMEA data, or just let people pre-type them in and then cut and paste when it's their turn
- Easy to just leave computer on and read a transcript of the net later-- for people like me who tend to sleep through radio nets
- Easy to jump up or down in frequency slightly for side conversations without taking up time on the net
- Low power requirements (and no annoying radio breaking squelch with static all day), so folks who want could leave their radio and computer on all day to listen for 'chat room' style traffic.

Fancy software could potentially form an ad-hoc mesh/repeater network, for very large graphically dispersed cruisers nets that can reach much further than a single net controller. So, for example, relays could be automatic, and a single net could cover most of the South Pacific. Automation of the net controller type job, and the written transcript, would make it OK to have a very long running net with many people, since no one would have to be there the whole time to participate (ie-- the computer could beep if someone's callsign is mentioned in the net, or when the checkins are over and it's time for the weather, and etc).

More nerdy folks could host a VHF/HF repeater on their boat, so that, say, a boat out in the anchorage with good HF reception could repeat the net on VHF for folks in the marina or anchored closer to town with bad HF reception.

Has there been any work on something like this, or other people kicking around this idea in their heads?

[msponer]

Oh, and just thinking out loud:

- A satellite/wifi interlink for the net. So people with just sat phones or wifi can also participate in the net/community. I don't know the details of 'third party traffic' to repeat the satellite checkins over HAM or SSB, but there may be a way to do it.

- Check-ins could be placed on a map. So people can easily see where everyone else is who check in, and maybe overlay the weather they report on the same map.

[ViribusUnitis]

It would be ideal if there was some version of packet radio for HF, with a decent baud rate that approached a pactor II level.

The problem with the basic psk31 is that only two radios can be linked together on one frequency at a given time. A packet radio system would utalize IP addresses, and a time division multiple access to allow several radios to connect all to each other at the same time.

Packet HF radio equipment exists, but it's not very reliable, and has a rather low transmission rate.

I have no idea how to get such, I just figured it would be cool.

[msponer]

The low transmission rate is fine for a cruisers net. A typical checkin with callsign, lat/lon, speed, course:

WB3ABC,-17.520,149.560,8,270

That's 27 characters, or ~7 seconds of PSK31. Adding weather would be another 2-3 seconds of transmit time, depending on how much detail people go into. And that checkin will reach much further than an SSB voice checkin.

PSK31 only allows one person to transmit at once, but multiple people can listen. And it doesn't require any hardware, so there is nothing to buy past making a cable to your computer. Even without a cable, you can turn up the radio and let the computer listen through it's microphone.

Maybe it would be neat to come up with a basic data format and operating procedure for a PSK31 net, then it's easy to make that the base that people with more advanced PACTOR modems or Iridium phones can then download a transcript of the net and have it displayed graphically (or as a layer in their charting software, or maybe hack it into an AIS data feed), plus with a transcript of whatever weather and news was discussed. Then consider adding the last x hours of Pactor/Iridium/WiFi/VHF PSK31 checkins or news to the HF PSK31 net.

Maybe there's an interesting way to transmit more data on the cruisers net. Say-- have a central frequency where all the traffic is repeated by the net controller, but people transmit one of several side frequencies. This could fit a lot more data. Maybe have several net controllers that are geographically dispersed and retransmit on a different side frequency, to have an enormous "All of the South Pacific" net, or something like that.

[conachair]

Originally Posted by msponer

PSK31 only allows one person to transmit at once, but multiple people can listen.

Don't know a great deal about it, but with winwarbler I can recieve txt from several stations at once on 14.070 - would this not work on a net as well?

Sounds like a good idea.

[ms100]

I like the idea.
¿anybody knows in which frequency is there any activity?

[atoll]

on a recieve basis only isn't this what navtex does?
and on a transmit and recieve the gmdss vhf system?

[afmstm]

I've been thinking along similar lines. At its simplest, PSK31 is a one-to-many protocol: one person transmits and many listen. With no new technology to create, this would work now.

There are many existing PSK31 software tools: eg DigiPan, etc. These allow you to monitor multiple conversations at once. The interesting thing about this, is it actually allows many to many conversations. It would not be unreasonable to have several boats checking in at the same time on different channels and everyone would be able to see (assuming they have enough signal strength). If using standardized messages, it would be straightforward to automate reading the data. DigiPan already does this sort of thing for recognizing call signs, etc.

There are many such frequencies depending on propagation, country etc. E.g. 7070, 7080, 14070 and others.

Probably the main inhibitor to this being useful is a critical mass of people who will take part. The technology is mostly all there.

Van

[Goudurix]

Very interesting!
@Atoll: Navtex is of course MF and doesn't have a long reach (several hundreds of miles on my standalone NASA navtex receiver but using the HF transceiver and its wire antenna, laptop and MultiPSK or FRISNIT navtex decoder I can receive local navtex stations as far as Portugal (to Belgium).
PSK31 on 14Mhz or 18 Mhz can give you > 5000 nM of reach.

There are also the newer PSK modes like PSK63 or 250 that are very fast and could be used to send larger texts eg weather forecasts by the net operators.

Jan ON3ZTT
SY Goudurix

[Patrick_DeepPlaya]

This sounds like a great idea, how about following behind an existing net and getting one of the weather guys to send their forecasts over to a netop or join. To begin with though, I would be up for trying to meetup following an existing net.

I will need a few days to sort out the tech side. I was attempting to use mmtty today and 'I' could hear rtty through the static but the SW could not. I think I need to add DSP to my icom m710.

I'll look into digipan.

-p
W7PEA

[Patrick_DeepPlaya]

OK... I've had visitors in town on the boat so I've not had time to geek out much but i'm back at it.

I have an M710 and there's not much detailed sharing about it going on so I created a new M710 Users Group ICM710 : Icom ICM710 Users Group I'm hoping much of the "how-to" stuff specific to that radio can go there over time. I'll write up what I do when I get it working.

I have been able to use a simple 3.5mm jack from the speaker output to the Line In on my PC and been able to "hear \ see" some RTTY using MMTTY (See group MMTTY : User group for MMTTY SB RTTY Software by JE3HHT ) I have yet to nail down the cabling to send with MMTTY.

I've also tried RCKRTTY (See Group rckrtty : RCKRtty ) which is supposed to work with TNCs, but I 'm not sure if my modem is supported (SCS PTC-IIUSB).

I should be able to make a cable to get MMTTY to work though, I'd buy one on EBay, but as I'm in Mexico getting that here will have to wait till someone come visits us.

I also thought I could just telnet into the SCS PTC-IIUSB and type all the commands, but that seems to be way more complicated than I thought it was going to be.

I'll save everyone the boring details about all this, but just wanted to say that I'm still excited about this and once I nail down the how-to of this I'd love to help get some actual nets up and running!

If anyone has the M710 and has all this working do please drop me a PM.

Thanks!
-p

[Patrick_DeepPlaya]

Ok all things work on my side.... Worked West Virginia and North Carolina from Mazatlan.

Who wants to try a test run at a net?

-w7pea

[Doug Pollard]

Hi all, PSK31 is a thing I am interested in. I haven't tried it yet I but it seems a really good solution to communication and getting messages home to family as well as weather forecasts. The only problem I have is no Vox but I guess I an get around that. My Alinco transitive is Hf with Fm and I guess I am wondering I will be able to communicate with anyone nearby with my signal wanting to bounce far off.? I guess I will have to read up on this some. 10 meters might work close up. Am I looking for problems? Doug

[Patrick_DeepPlaya]

I'd read up on normal PSK31 Operation and making contacts with other HAMs. there was zero to no momentum for a Cruisers PSK net when I was still out cruising and with the great availability of cell and WiFi even remote areas, I suspect that trend will continue.

But, PSK is fun and if you're into HAM Radio then go for it, but I think you'll get more interaction with other HAMS than you will other Cruisers. The HAMNets always seem to get a kick out of it when they learned I was operating from a sailboat.

Keep at it and enjoy!

73
W7PEA \ Patrick

[SM6WET]

About third party use. Very few countries amateur radio rules permits 3rd party operations although anyone, even non-hams is allowed to listen.

Some other great things with psk31 is that it is so narrow banded that one can listen/read multiple stations at the same time.
Due to narrow band usage the characters are transmitted with little power and fast making it very energy efficient. You get far with 5-20 watts with a reasonable antenna while using packet or Pactor 100w out in the middle of nowhere is really too little.

One thin though... My recommendation is not "only" to make the wire between the radio and computer. Make it with opto-couplers to protect both your computer and radio from eachother.
If you don't know how to do it there are stuff to buy for very small money.

Cheers