Communicating computer to computer

I've been digging into digital comms via radio, APRS, DTMF and a device called the "gotenna" for cell phones for 7 days now. I've read so much over the past week I got a migraine trying to find the info I want.

I give up - I'm going to out right ask some folks who might be in the " know " :

I'm looking to send digital media ( SMS - instant chat, data if possible, pictures, files possibly ) from my computer to someone elses computer over the air waves.

I DO NOT want to use someone else's network ( The internet, Cellphone towers ) or become part of the APRS network. I want this to be a " hey, turn to (_____frequency___) and have your computer on, ready to receive ". If no one is there to receive it, it just never got received. It's not stored somewhere, and forwarded.

I want to be able to open up a program on my computer, and send text to them as if I was in a chat room. Possibly have others listen in and respond live if they are within range. Maybe be able to send files ( limited ).

I'm imagining being able to hook up to my ham radio's mic port via a USB connected to my PC and send and receive info via that.

Does this exist? Or must I join the already existing network of APRS?

A TNC will do something similar, but it will be painfully slow.

Probably not what you want to hear, but if you invested in some new digital radios, many of them will do that right out of the box.
I run Kenwood NexEdge radios at work, and they can be set up to transfer files between radios. It's still pretty slow, but it's as simple as hooking up an RS-232 cable to the back of the radio and setting up the radio correctly.

You could also look at the Icom 1.2GHz D*star radios. They had enough bandwidth that you could do near ISDN speed (around 128K)

There are some point to point network links that run in the 900MHz ISM band. Might be able to hack some of those to work in the 900MHz ham allocation, but it sounds like point to point stuff isn't what you are looking for.

Other than that, I'm not sure what else is out there. I played around with packet radio back in the late 80's early 90's, haven't touched it since.
I did some APRS a few years ago, but that won't do what you want.

I'm sure someone will have some better ideas. The solutions are out there, it just takes some creativity.

You can always go from station to station(s) using either simplex, through a repeater (yes, it does work) or a store-and-forward arrangement. There is AX25 (packet), soundcard digimodes using a program like FLdigi, etc. We use whatever works here in NYC and beyond. These techniques are usable on HF, VHF/UHF, etc.

There are amateur IP mesh networks being developed out of modified WiFi gear. There are part 15 point to point microwave links that can be operated in Part 97 frequencies with increased performance. There is some 9.6 kb gear that's used for packet backbones on 219-220 MHz (operating under part 97).

It sounds like the mesh network is what you have in mind. People are essentially creating an IP network similar to the internet, but transported via Part 97 radios for amateur traffic only. This is happening NOW, in a city near you.

You don't have to join someone else's network, create your own if you want. Just keep in mind that this is done on microwave frequencies. The bandwidth for anything other than text messages doesn't exist on lower frequencies.

1. SSTV will handle sending images back and forth.

2. Various digital modes will handle messaging using text you type in using your computer keyboard. Something like PSK31, RTTY, and the like. Others might join in if you convey that its a net or invite others who may be reading the text.

Either of the above can be accomplished with a computer, proper cables to your rig, and a program to handle those features. DM780, which is bundled with the free version of HRD will do the above. There are other free programs like MMSSTV, Fldigi, and others.

You will find plenty of information out there on SSTV and digital modes like PSK31 and RTTY. They've been around for a while. Also, while you can use your computer sound card, I use a SignaLink USB device to handle the sound card function. This eliminates any computer "sounds" during transmission, which would disrupt the data.

All of this is done over the air. No cellular towers or the Internet is required. As n2nov pointed out, you can use these modes over HF/VHF/UHF.

I can also do the above with two different applications on my phone. Yes, I can send and receive SSTV and PSK31 using my phone and a radio to transmit and receive. I just hold the key down to TX.

(APRS is a good solution for sending messages. I use that too.)

GoTenna is phone to phone over MURS.

What you are really wanting appears to be a private IP network, maybe even a mesh.

I have done this using packet on 2 meter band back in the 90's worked pretty good just for chating back and forth,you can send files but its going to be really slow and for aprs don't think that's what you are looking for,for sending files the mesh network would work better for you good luck on you project...........

Computer/computer messages Using Inexpensive ISM ICs

In May KF5QZS asked about communicating computer to computer without using anyone's network. You can, of course, do this using 1200 baud "packet radio" using any ham-rig and a TNC, plus a computer. This speed (1200bps) is fine for typing text messages but a little slow for larger computer files or pictures (image files). You might check out my experience using digital transceivers made from cheap ISM ICs, at http://w5vwp.com/moteino.shtml. The web-page describes how to start using inexpensive single chip low power 433mhz or 900Mhz FSK digital transceivers. It describes how I constructed a 4 watt 56kbps digital transceiver for about $75. It has a range of about 3 miles to a mobile 70cm antenna. It plugs into your computer's USB port. I put firmware for the moteino (arduino clone) on http://github.com/griff2/rfm69rptr. This firmware displays whatever you type on your keyboard to the screen of the "remote" computer, and vice versa. The digital transceiver is based on a MOTEINO device ($21) from
LowPowerLab | Adventures in the land of low power embedded systems plus a Chinese FSK 4 watt power amplifier ($53)I purchased on ebay.com. This approach gives hams an alternative that is about midway between the existing fast data rate but short non-mobile range provided by WiFi gear, and the slow data-rate but longer range of packet radio. For even longer range, try using directional antennas and/or the Down East Microwave (Catalog) 70cm 30 watt linear power amplifier, model 7025PA ($215).

Griff W5VWP

Another communication device/software computer to computer is rms express, they have one section of it, I believe called person to person and it works very good also, and it is FREE also.
DOCTOR/795

doctor795 said:

Another communication device/software computer to computer is rms express, they have one section of it, I believe called person to person and it works very good also, and it is FREE also.
DOCTOR/795

Click to expand...

Yes, RMS Express is a good choice for peer to peer communication as long as you have the right equipment to go with it. I have it installed on my laptop for use in my Go-Box that has both a Kenwood TM-D710A VHF/UHF FM transceiver and a Yaesu FT-857D HF/VHF/UHF all-mode transceiver in it. I need to get a Packet TNC and USB cable yet so I can get into my packet node as well.

n2nov said:

You can always go from station to station(s) using either simplex, through a repeater (yes, it does work) or a store-and-forward arrangement. There is AX25 (packet), soundcard digimodes using a program like FLdigi, etc. We use whatever works here in NYC and beyond. These techniques are usable on HF, VHF/UHF, etc.

Click to expand...

+1 on the FLdigi. I played around with it on vhf/uhf a while back and had good results.

KF5QZS said:

I've been digging into digital comms via radio, APRS, DTMF and a device called the "gotenna" for cell phones for 7 days now. I've read so much over the past week I got a migraine trying to find the info I want.

I give up - I'm going to out right ask some folks who might be in the " know " :

I'm looking to send digital media ( SMS - instant chat, data if possible, pictures, files possibly ) from my computer to someone elses computer over the air waves.

I DO NOT want to use someone else's network ( The internet, Cellphone towers ) or become part of the APRS network. I want this to be a " hey, turn to (_____frequency___) and have your computer on, ready to receive ". If no one is there to receive it, it just never got received. It's not stored somewhere, and forwarded.

I want to be able to open up a program on my computer, and send text to them as if I was in a chat room. Possibly have others listen in and respond live if they are within range. Maybe be able to send files ( limited ).

I'm imagining being able to hook up to my ham radio's mic port via a USB connected to my PC and send and receive info via that.

Does this exist? Or must I join the already existing network of APRS?

Click to expand...

Broadband-Hamnet

https://www.hamwan.org/t/Wiki+Home+Page

There threats to our5 Ghz band so get up there and use it.

KHF4UWL

KF4UWL said:

Broadband-Hamnet



https://www.hamwan.org/t/Wiki+Home+Page



There threats to our5 Ghz band so get up there and use it.



KHF4UWL

Click to expand...

I fell out with HSMM-MESH when they wouldn't actually support anything other than the WRT54G (which were getting hard to find at a good price). Then I started playing with Ubiquiti and Mikrotik…and now I'm a WISP.


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W5PKY said:

I fell out with HSMM-MESH when they wouldn't actually support anything other than the WRT54G (which were getting hard to find at a good price). Then I started playing with Ubiquiti and Mikrotik…and now I'm a WISP.


Sent from my iPhone using Tapatalk

Click to expand...

Well if you know what your doing you can roll your own os , use your own hardware and use their network.
I mean they are using a version or open wrt that runs on almost everything.

Sstv for image. Packet for text (real connected packet, not that APRS garbage) You can set up a packet BBS and have people connect to it. File transfers are a part of that,too.

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