mspot

An M17-only hot-spot (or repeater)

Description

This open-source project will build an M17-only repeater or hot-spot for amateur radio. The design goals for this project include:

• Easy to build: Because the mspot repeater is a single application and is complete. It includes a novel M17 gateway that can connect to both M17 and URF reflectors.
• Easy to configure: With a single, self contained application, there is just a single configuration file, and the project builds an additional program, inicheck, that will intelligently analyze your ini file and reports any problems it finds.
• Easy to use: mspot includes many RF-base commands to manage its connection state and responds to commands with voice messages, making mspot ideal for a mobile, smart-phone tethered repeater. I am hoping it is also useful to sight-impaired hams.
• Minimum executable size: mspot is tiny, especially when you compare it to the multi-mode alternatives.
• Excellent reliability: You'll be the judge of that. Try it and find out.

It should support most any MMDVM-type modem because a significant portion of the project is based on a stripped-down earlyer version of G4KLX Jonathan Naylor's MMDVMHost. Unlike MMDVMHost, this project does not support any display device. It also does not support file locking, transparent port, or remote control.

This project will build mspot, a single executable program that has a built-in M17 gateway that will connect to both M17 reflectors and URF reflectors. The gateway portion of mspot is unique. It doesn't use the popular time-slice method characterized by a clock() routine, but rather uses a kind of pass the baton control scheme.

Building mspot

These instructions are for Debian-based operating system.

After making sure your system is up to date: sudo apt update && sudo apt upgrade

There are a few things you need: sudo apt install git build-essential nlohmann-json3-dev

Then copy this repo: git clone https://github.com/n7tae/mspot.git

Within the mspot folder, copy a few files to this folder (don't forget the period at the end!): cp config/{mspot.*,*.txt} .

Then you your favorite text editor to modify two of these files to your needs. Comments within these files will help you decide what you need to do:

• mspot.mk contain compile-time options.

You can then build mspot: make

Configuring mspot

• mspot.ini sets run-time options.

You may have noticed that two programs were created at the build stage: mspot the M17-only repeater/hot-spot, and inicheck, a program that will check you initialization file for errors. inicheck tries to be very thorough. In addition to making sure that all needed variable are define and have reasonable values, it checks that path names are pointing to existing files on your system, and that those files are the kinds of files they need to be. Do: ./inicheck mspot.ini. If any errors are identified, mspot won't run.

Each parameter in the example inifile is commented to help you understand what it does. Keep in mind that many of the parameters in the [Modem] section have no meaning once you set a Protocol. Using inicheck will at least tell you if your UartPort is pointing to a character device. If you are having trouble connecting to an older modem and your sure the UartPort is correct, try reducing the UartSpeed to 230400 or 115200.

In the Building section, a few .txt files were copied. These files are for connection information. M17_Hosts.txt contains a list of all M17 and URF reflectors registered at dvref.com and contains a time-stamp so you know exactly when it was created. You can build an up-to-the-minute accurate host text file with the make-m17-host-file program that is part of the ham-dht-tools repository. The second, MyHosts.txt is a place for you to add other reflectors that aren't registered at dvref.com.

Starting mspot

To start mspot, go to its repo folder and type ./mspot mspot.ini. Then [Log] DisplayLevel messages will be printed in the terminal window and if [Log] FileLevel is greater than zero, log messages will also be written to the folder and file specified in the ini file.

Alternatively, you can have mspot automatically launched on system boot up. To get started, copy the service script: cp config/mspot.service . and then edit the copy by changing the values within the <> brackets. Then do a sudo make install. You can do sudo make uninstall to stop this. Please note that installing and uninstalling require root privileges, but mspot can run with user privileges as long as the user is a member of the dialout group. In this case, you will want to enable [Repeater] IsDaemon and then be sure to specify the correct login id for [Repeater] User. If it's not starting correctly, look for the cause in the ini-specified log file and/or the systemd log: sudo journalctl -u mspot. If mspot launched successfully manually but won't install, more than likely you have a problem with your mspot.service file.

Dialout

The user that executes mspot needs to be in the dialout group! Do a getent group dialout. If the user is not listed, do a sudo adduser <username> dialout, where <username> is the login name of the user. After this, you can verify with another getent command.

Using mspot

Make sure you have an M17 radio on and set to the proper frequency. You'll hear a startup message whenever it launches.

The following #destinations work:

• ECHO or E will parrot back anything that's transmitted to the repeater. Maximum recording time is two minutes.
• STATUS or I will play a connection state message.
• You can connect to any known reflector module by putting that reflector's callsign and module letter in your radio and keying up. Be sure the reflector module letter is in the ninth position! For example M17-QQQ A or URFQQQ C. Once you hear a message that it's connected successfully, the next time you key up, you'll be transmitting into the reflector module. Any time you you want to transmit into the reflector you need to have your destination set to the reflector and module to which you are connected.
• UNLINK or U will disconnect you from a connected reflector module. Please note that mspot has to be in a disconnected state before you can connect to a reflector module. If you try to change modules or change reflectors, your transmission will be ignored and a connection message will be played when you end your transmission.

There are two other commands that you might find useful:

• RECORD or RECORD ? , where ? is any valid M17 character, will record and then play back a transmission. Without a valid ninth character, the recorder transmission will end up in the specified audio folder with the name ECHO.dat and this is exactly what ECHO or E does. RECORD A will end up in the specified audio folder with the name alpha.dat, RECORD B will end up in bravo.dat, and so on. Likewise RECORD 8 will end up in eight.dat and the three valid M17 punctuation characters will end up in obvious named files. Your recordings will remain until they are re-recorded, or they are manually removed.
• PLAY or PLAY ? will play the message already recorded at that location, if it exists.

The echo and record functions will not record more than two minutes and the recording must be at least one second long.

More about voice message

The robotic voice prompts currently being used are generated from a rather old open-source program, espeak. The first time you hear it, it might be a little difficult to understand. For example, the first time you hear espeak say "hotel", it may be hard to recognize. However, it gets much easier with repetition. However, if you are interested in recording your own voice messages or want to re-record messages in a different language, see the related M17AudioTools repo. These are the tools used to create the mspot voice messages.

License

This software is published using the GNU GPU, Version 2. Please see the enclosed LICENSE file for details.

Finally

There is still a lot of work to do before it will be really useful to my target audience.

73 de N7TAE