Building a code plug for BrandMeister.

When building a code plug there are three stages.

1. Installing the talkgroups, reflectors and personal identifications.

2. Building the frequency tables.

3. Building the zones.

These have to be done in this order as you can’t build frequency tables without groups and you can’t build zones without frequencies.

When creating the talkgroups and reflectors in the contacts list, add all of them. Research all the sources. If you want to add personal calls do so, but only those you believe you will need for personal interaction, you’ve room only for a 1000.

When creating your frequency lists, research each repeater and look for the norms, that is to say determine on which slot certain talkgroups should be active. This is not restrictive practice, it’s just common sense. In most cases talkgroup 9 should be found on both slots, possibly talkgroup 10 and talkgroup 99 as well.

On slot 1 single digit, double digit and triple digit talkgroups are standard. Slot 1 should contain international, national and language based talkgroups.

On slot 2 are found generally the 4 digit talkgroups like uk calling 2350 and chat groups 2351-4. If needed talkgroup 9 can be used to make reflector calls to other reflectors, but it is superfluous to connect to 4400 reflector as this corresponds to talkgroup 2350 already available in an open unrestricted repeater.

For repeater sysops it is a matter of balance, either you want a repeater for the users or you want a repeater for accessing the wider world, or a mix of the two. If you are running multi-mode, then you have to juggle the needs of the many to outweigh the needs of the few. Dynamic talkgroups are those that are activated by PTT at the repeater, and remain active for 10 minutes and only for as long as no one reactivates in the time period. Fixed talkgroups are those that are locked open 24/7 by activating this function on selfcare,

By and large UK Brandmeister repeaters are open to the UK on slot 2, and internationally on slot 1, except where they have chosen to cluster.

This means 2350-2354 are either dynamic or fixed on slot 2. 80,81,90,91,235 etc are dynamic or fixed on Slot 1.

Talkgroup 9 is standard for local users on both slots, with the addition that on slot 2 a user can connect a reflector on this talkgroup. As I commented above, there is little point connecting to reflectors 4400-4 as the associated talkgroups are already available in this scenario. However it leaves the possibility of connecting to a foreign reflector on talkgroup 9 slot 2 should a user demand it, such as 4639 USA national (3100). There is the possibility of leaving open talkgroup 3100 as dynamic but there is a problem here. Dynamic talkgroups have that fixed time-out and cannot be disconnected while they are alive, but reflectors do not time-out, but they can be disconnected by 4000. I say they can’t time-out, but a sysop can force a standard time-out in selfcare. What I have noticed however is that a dynamic talkgroup called up by a user can supplant one called earlier.

As I see it Mmdvmhost, as in most homebrew repeaters like F5ZLR and GB7SO have all talkgroups unrestricted, which I can see creating issues on a repeater unless the sysop takes a handle on it. Generally such talkgroups are dynamic, activated by PTT by a local user. They permit two way traffic for the duration they are active normally 10 minutes after last transmission outbound. A sysop can fix selected talkgroups in selfcare, so that they all remain open bi-directionally for the period selected, either full-time or part-time.

There is also a way whereby a sysop can partially block unwanted talkgroups from being accessed, and that is by using the whitelist command. By listing acceptable talkgroups in each slot, he effectively removes the unwanted talkgroups from the repeater, but this does not prevent their associated reflectors being accessed should the need arise. I have deliberately excluded how this is achieved, unless a sysop asks for it. It should not be applied lightly.

By removing this command, the repeater reverts to fully open as standard.

Remember there are only two available channels and we all have to share.

In Summary then if you have a UK BrandMeister repeater that you would like to populate to the best advantage, This is my recommend.

For Slot 1 TG9, TG80,TG81,TG90,TG91 and TG235 in other words National and International.

For Slot 2 TG9, TG2350, TG2351, TG2352, TG2353 National and regional and local chat.

If you want Scotland then add TG2355 as well.

There are other talkgroups for clusters, and for bridges to other modes, so you can add those as well.

For other Talkgroups consider using Reflectors on TG9 slot 2.

The only drawback on building a standardised zone in a codeplug is that some repeaters will have talkgroups blocked or simply not-open.

Each repeater keeper has the right to govern his domain as he sees fit, but this becomes more problematic when it is a repeater governed by committee. It is even more difficult when there is a multi-mode repeater in use.

When it comes to it, any repeater will have a settling-in period for the sysop to examine the use of the unit and tune the use of it appropriately.

Primarily this is a hobby, a pastime, and not a job, a fact that some people frankly forget. Enjoy it but not at the expense of others. Regards, Chris F5VMR G4NAB.


Kiss Comms



•Nothing is worse than a radio operator that never listens first and talks over a conversation already in progress. There could be vital communications already in progress.
•Announce your presence clearly and concisely, then wait and listen again.
•Make your call then and only then if the channel is clear, and do so in a fashion that if you were the intended recipient of such a call, you would be in no doubt of the identify of the caller and his intended message. Prolonged calls are unnecessary on accepted calling channels.

•In establishing a contact, the essential parts are that you have correctly identified your correspondent and that he and you are in the position to exchange information. There is nothing worse than being asked to repeat vital information. Proceed only when you are both ready.
•M3xyz from g4abc, are you ready to copy, over!
•G4abc from m3xyz, ready to copy, go ahead, over!
Yes, these two examples are extreme but illustrate the message.

•If you are going to conversation mode, restrict your topics.
•Talk no longer than 3 minutes at a time, and less long on a repeater. This allows you to think more about what you are saying, rather than thinking about what you want to say next.
•Censor yourself. Not everyone wants your full station details from the outset. Too many items in the list risks information overload, and loss of interest. Not everyone has the same level of enthusiasm for certain subject matter as you. If you wander on, your correspondent may get interrupted in his listening by local matters such as a phone call, or disappear to make coffee due to boredom. Offer only essential information at first.
•At the and of such an extended transmission always re-identify yourself and your correspondent on conclusion, m3xyz from g4abc, and leave good breaks between transmissions.

•Remember that any remarks you make are not private.
•Your language, including remarks that may be less complimentary about a third party are open to interpretation by others.
•Say nothing that you would not like said to you, or about you, if spoken by others. If you cannot say anything nice, then say nothing at all.
•Try to use accepted speech rather than acronyms, mnemonics, or catchwords as not everyone may be as fluent as you. If you use a short cut, know what it means if it calls for explanation. This is especially important in the emerging technologies, as a lot of terminology has been confused, such as in talkgroups and reflectors in Digital Mobile Radio.
•Politeness costs nothing, if you disagree, agree to disagree, don’t argue about a point, as in the end neither of you will be right and you will hate each other.

•If you are the respondent to a call that is not of the standard that is outlined here, raise the standard and apply this etiquette. Just because the other caller lacks the expected protocol, it may be that he or she has not yet had the benefit of receiving the appropriate tuition, and you will now be best placed to give it by example.

•Where possible leave listeners in no doubt that you have finished the conversation, or that you are leaving the channel.
•Naturally there are times when batteries fail and correspondents are no longer in range, that is inevitable, but clear the channel anyway for the benefit of others.

•Chris G4NAB/F5VMR is a retired Hampshire police officer (1971-2003), where for many of his 30+ years of service was a professional radio operator/ dispatcher/ controller in all the county control rooms during their evolution from VHF to UHF over the past 45 years. He gained his first amateur licence G8POB in 1977 with a pass in the City and Guilds Amateur Radio examination, and having passed the Post Office Morse test at Niton on the Isle of Wight, gained the call G4NAB in 1983. He retired from the police in 2003 from the police control room at Netley, Southampton. He now lives in France and continues his amateur activities in French as well as English.

Aargh! I hate that!

Bad Spelling, Bad Grammar, Using the Wrong Word, Ill-considered comment, and the list goes on.

Since the advent of public media such as FaceBook some people have shown themselves in poor educative light through one thing or another.

Do simple things get up your nose?

When you say the letter “h” there is no “h” in “aitch” so when you say it so don’t say “Haitch”!

Allowed or aloud. Is it “allowed” or permitted? Or do we say it aloud or out loud?

There, their, they’re: There it is! It’s their problem. They’re not in possession of all the facts.

Your, you’re: Your mood is an indication of how you’re feeling.

Where, wear, ware: we’re, weir: Where are we? What shall I wear? Ware the danger of werewolves! We’re all aware of the water going over the weir.

Would have, should have, not “would of” or “should of”. If I had the money I would have bought it. If it was necessary, I should have.

Why use expletives when there are many words available? Yes of course you might be annoyed at something, but your state of mind will not enable you to deal with the situation. You will be considered more intelligent and comprehensible if you have a more fully developed vocabulary.



The right thing to do?

“It is but chance, an accident of birth that give us the attribution of one nation or another, and our forebears and peers that direct us in our national pride.

But whether by history or fact or rumour there are those undeniable rules of law: that without evidence there are no truths, that without proof there is no guilt, and beyond reasonable doubt means that mere circumstances alone are not enough.
Circumstancial evidence does indeed give rise to further questions, as does strong suspicion but neither are just causes for open accusation.
Such accusation is not a tool of enquiry, neither is it wisdom to declare it when other paths exist albeit less trod through fear of seeming weak in others’ eyes.
Simplicity is not a weakness, neither is a little trust, but fear is a weakness as it leads to indecision and mistrust and division.
Criticism of a person rather than the act is a show of failure, the last resort of a lost cause, the last arguement on an erroneous path.
Courage of a different sort is the key, to grasp the the hand of the other and understand that differences are what make us, and the errors that are made, are errors that are lessons for the future.
As nations we are different, but as individuals we are the same simple beings with needs, hope and aspirations.
Of course we must indeed guard against extreme ideals that would seek to destroy us, but in that regard, learn to distinguish those which would be so damaging, and tolerate those other things with which we might not so readily accept. The balance which we apply will serve us better than base rhetoric, and jingoism. #notinmynameteresamay”

Raspbian Stretch and Svxlink

SVXLink and Raspbian Stretch
Installation from scratch


  1. 1. Raspberry Pi B+, 2 or 3:1
  2. 16 Gb MicroSD Card:
  3. PC:
  4. USB Sound Card:
  5. Time Allotment: 60 Minutes


Tip: You do not need to be an expert in Linux but in following this guide you will understand everything you need to know for this project


  1. On the PC install a suitable image writer.
  2. Download from the latest version of Raspbian Stretch – the Full version.
  3. Save the download and expand the image to a suitable location using 7-zip.
  4. Insert the SD Card and run the ImageWriter program, selection the .img from the previous step.
  5. Write the image and wait for the prompt upon completion.
  6. Before removing the card from the PC, create an empty file named “ssh” without a file type and save it to the boot sector on the MicroSD card, but don’t save it in the /boot folder. Tip: This action permits SSH access on boot up, and you won’t need a screen or keyboard.
  7. Remove the card from the PC

Raspberry Instruction

Tip: Before booting the raspberry with the new SDCard, ensure that it is connected on an adequate power supply and connected to the same network as the PC. You will need the application AngryIP scanner, and SSH app installed on the PC.

  1. Boot the Raspberry
  2. Run AngryIP scanner to determine the IP address of the Raspberry.
  3. Note down the IP address, and close AngryIP.
  4. Open SSH and type in the IP address for the Raspberry
  5. Open the terminal screen and type the user pi and password raspberry
  6. Now you are ready for the next steps in raspbian linux. Be careful of your syntax as all commands are lower case, but if an uppercase is shown it must be used.

Updating the Raspberry

Tip: This step is absolutely necessary. Type the commands at the prompt, and wait for each of the commands to complete. There is no need to expand the operating system in the MicroSD Card, as Stretch does this on first boot.

  1. sudo raspi-config to open the configuration menu then at option 5 enable VNC
  2. At option 7 Advanced options, select A5 for Mode 16
  3. Exit raspi-config, but do not reboot yet.
  4. At the prompt type sudo apt update
  5. At the prompt type sudo apt-get upgrade
  6. When the commands have all finished type sudo reboot. Exit the SSH app.

Entering the Raspberry by RealVNC

  1. On the PC, run VNCViewer and use the IP address to enter the Raspberry Desktop.
  2. Use the username and password from the previous steps. You will see the graphic appear of an open road. In all aspects the desktop is similar to a Windows desktop.
  3. At the top menu bar click on the terminal icon to open a terminal window in the desktop. You are now ready to continue the preparation of the Raspberry for Svxlink.
  4. The next steps may require a reboot, but always return to this position to continue the set up.

Installation of the USB Soundcard

  1. Install the USB Sound Card on the Raspberry then in the terminal screen type the following command at the prompt.
  2. sudo nano /etc/modprobe.d/raspi-blacklist.conf
  3. and type the following line.
  4. blacklist snd_bcm2835
  5. then save the file (cntrl-o) and exit (cntrl-x) then type
  6. sudo nano /lib/modprobe.d/aliases.conf
  7. locate the following line
  8. options snd-usb-audio index=-2 and insert a “#” before it, then save and exit.
  9. reboot.

Sound Card Configuration

  1. Re-open RealVNC viewer to the raspberry pi.
  2. Re-open a terminal screen and type the following command at the prompt.
  3. sudo alsamixer
  4. you should now see that your USB sound card is the default sound card. type cntrl-f5 to view all the sliders.
  5. set the first slider to around 60% the second to zero, the third to a maximum of 12 and in the fourth type M to mute the amplifier.
  6. Type escape then type
  7. sudo alsactl store This will save these settings even after re-booting.
  8. sudo adduser svxlink (This will prepare the card for the installation of SVXLink.)
  9. Make the password svxlink, as you won’t need to use this any further.
  10. Test the installation by sudo aplay -l.

Compiling SVXLink successfully

  1. To insure git is installed, type sudo apt install git, although I have found it installed as standard.
  2. At the prompt in the terminal type sudo git clone
  3. This will give you a download of the the latest master of svxlink.git including svxreflector, svxserver and svxremote into a folder called svxlink in the current user.
  4. When it is safely downloaded, go to the instructions page to add all the necessary additional software. The list is very important and is found on the project page of at install.adoc. Some of the software is standard in Raspbian Stretch so you may find the system reporting this fact. The list of -dev packages is more difficult, but I will show you the following pointers.
  5. To install the top list of software simply type sudo apt install gcc g++ make cmake groff gzip doxygen tar git
  6. For the second half of the list install each of the packs individually.
  7. sudo apt install libsigc++-2.0-dev
  8. sudo apt install libpopt-dev
  9. sudo apt install tcl8.6-dev
  10. sudo apt install libgcrypt20-dev
  11. sudo apt install libasound2-dev
  12. sudo apt install libgsm1-dev
  13. sudo apt install libspeex-dev
  14. sudo apt install librtlsdr-dev
  15. sudo apt install libqt4-dev

If the system responds with a y/n query always go for the y and you will have no issues. The final line sudo apt install alsa-utils may attract the response that the latest tools are already installed.

The Compilation
Now follows the commands below.

  1. cd svxlink/src
  2. sudo mkdir build
  3. cd build

Now we start compiling. Type the following line EXACTLY, including / \. as they are important for the syntax. This command must go one one line. The final two .. after a single space are important too. The command will take several minutes to execute.

  2. sudo make – This command will take 30-45 minutes to run dependent on processor used.
  3. sudo make docThis prepares all the documentation and manual files.
  4. sudo make install This compiles all the software into the operating system.
  5. sudo ldconfig

Installation of the Sound Files

The software is now installed, but not yet ready for use. We need the Language files. My preferred method is as follows.

cd /usr/share/svxlink/sounds – We are now in the correct directory. There is a useful command wget that downloads a file from a web source.

sudo wget http://(websource) filename
If you want the french language…

sudo wget

sudo tar xzvf fr_FR.tar.gz – unwraps all the necessary files into their proper folders.

If you want the en_US files they are on
If you want to make your own then download DSpeech from Dimio and play with that. However the finished .wav files need to be imported into Audacity, trimmed and exported as microsoft .wav files. This changes the twelfth bit from Hex 12 to Hex 10, to enable them to work in svxlink.

Setting up the GPIO ports

We need to setup the GPIO ports. The simplest way is to add the following lines to the file rc.local.

  1. sudo nano /etc/rc.local






# GPIO 17 as PTT to TX2

echo 17 > /sys/class/gpio/export

echo out > /sys/class/gpio/gpio17/direction

sudo chmod 777 /sys/class/gpio/gpio17/value

# GPIO 18 as Squelch to RX2

echo 18 > /sys/class/gpio/export

echo in > /sys/class/gpio/gpio18/direction

sudo chmod 777 /sys/class/gpio/gpio18/value

#GPIO 24 as PTT to TX1

echo 24 > /sys/class/gpio/export

echo out > /sys/class/gpio/gpio24/direction

sudo chmod 777 /sys/class/gpio/gpio24/value

# GPIO 23 as Squelch to RX1

echo 23 > /sys/class/gpio/export

echo in > /sys/class/gpio/gpio23/direction

sudo chmod 777 /sys/class/gpio/gpio23/value

#end of GPIO Section

#Remove # at start of next line for permanent reboot on power loss.

#sudo svxlink –daemon –logfile=/var/log/svxlink.log

These lines go immediately before the final

exit 0

  1. Save and exit the file.

Run Time

  1. The final steps are to set the parameters in /etc/svxlink/svxlink.conf and /etc/svxlink/svxlink.d/ModuleEchoLink.conf to enable your installation, paying attention to syntax and whether you are operating simplex or duplex.
  2. I have plenty more tips, but most of the answers are in the documentation on your MicroSD Card.
  3. Don’t forget to remove the # from the run line in /etc/rc.local to make your installation run at boot up.
  4. KISS principle – Do not overcomplicate your system. Ask yourself – Do I really need it? when considering changes. Why do you think that people want to see what’s occurring on the repeater when all they have is a radio and want to talk?

DMR Confusion and how best to avoid it.

The more I listen to DMR, the more I hear the confusion in numbers of users, apparent in the lack of understanding of how and why it works, mainly due to the uncommon propagation of terminology and the wrong context. So I hope the following discourse may help. Other modes are available but I am sticking with DMR for this article.

We start this program by understanding repeaters first of all. Some of this understanding is primarily BrandMeister related, but it can apply equally to other networks as the technology is the same.

Normally a repeater has two available SLOTS where the repeater manager has allowed them. The repeater manager can block use of these in the repeater firmware or mmdvmhost, thus SLOT 1 or SLOT 2 or Both can be closed off to users, although the repeater would be pretty useless without an active SLOT.

The next thing to understand is that a talkgroup is NOT a reflector.

Talkgroups are data routings within the system of servers. For reflectors see the specific paragraph below.

I am now going to restrict the next part of this discourse specifically to mmdvmhost repeaters, which are largely homebrew, although some of information may well apply to other commercial repeaters.

A repeater manager or sysop can Whitelist talkgroups within the repeater thus permitting controlled dynamic use, which means some transmissions may be refused on unwhitelisted talkgroups. I have noted this in the mmdvm repeaters that I have built. A log entry will show that an unauthorised talkgroup has been refused. However by omitting a whitelist command, a repeater can be dynamically open to all talkgroups anywhere, which can lead to anarchy.

A standard DMR repeater will have Talkgroup 9 as standard and active on Slot 1 and Slot 2, which give local communication only over the repeater. Any transmission on these talkgroups will never pass over the network. In technical terms these two talkgroups are Dynamic and PTT activated, however they can be made locally fixed or static by whitelisting them.

The repeater manager can also whitelist other talkgroups on the repeater by allocating them to a specific slot. So for example in the UK Talkgroup 2350 the national centre of activity is normally allocated to Slot 2, however on the 5B4CY repeater in Limassol it (2350) is on Slot 1. Having them whitelisted permits them to be Dynamic Talkgroups, but until permission is granted at the server, they can not be Static or Fixed talkgroups, that is to say fully active. Once this is so, all transmissions on the talkgroup can pass over ALL systems similarly configured without the need to blip the PTT to the repeater to open the link to the talkgroup.

On BrandMeister the method of fixed talkgroups is done through Self-Care by the sysop (repeater manager). A Dynamic talkgroup generally resets to off at the repeater output after a period of time, usually 10 minutes if unactivated at the repeater input. Fixed talkgroups remain on line, so that whenever there is activity, all systems with the same fixed talkgroups will open simultaneously.

I make a comment here that there is such a thing as repeater overload. A repeater keeper can put too many Static or fixed talkgroups on a repeater, I know as I did it in the beginning. If these Static groups are particularly busy and are on the same slot then this activity can render the repeater useless for 100% communication. This can occur even if the local activity around the repeater is light, as outside transmissions would block the channels. It would be better that these talkgroups would be Dynamic and available for local users by PTT activation as and when they were required.

Clusters are groups of repeaters that have agreed to participate in a joining by talkgroup, that has no wider propagation other than those in the agreement. This cluster can be local in nature as in the South West Cluster in the UK, or wider due to an interest in shared technology. Generally there will be no connection unless requested from outside the grouping.

For anyone setting up a repeater, there are two considerations. 1. the needs of the local users, 2, the need for interconnectivity to the wider world.

Looking across the network as a whole, slot 1 seems best used as an international medium with double and triple digit talkgroups, and slot 2 as a local/national medium with access to four or five digit talkgroups. There would be no need to fix a reflector as standard as these can be programmed by the users on demand, and subject to a reasonable timeout. 4400 would be superfluous as talkgroup 2350 would be the first choice of dynamic or fixed talkgroup, likewise 4401, 4402 etc. as 2351 and 2352 would become the dynamic equivalent talkgroups.

So far I have covered simple Talkgroup Connections that are channelled by connections through the server through the Talkgroups database. A repeater can be connected firstly and most simply by Talkgroups, or secondly and more dynamically through Reflectors.

Reflectors have a relational connection to a corresponding talkgroup, although not all talkgroups have a corresponding reflector. Reflectors have a two-fold purpose, in that primarily they provide a bridge out from a repeater to a wider context, or secondarily a bridge in permitting a whole new group of people on Hot Spots to access the available talkgroups via the reflector connections. Some reflectors are bridges to other modes, and other systems on other bands.

With a repeater on Talkgroup 2350, we find that it is accessible by anyone who can achieve a connection to reflector 4400, via the server system. Likewise a HotSpot user on reflector 4400 can communicate with all repeaters having a static talkgroup of 2350. Notice here that the talkgroup has to be static or fixed for the communication to be heard on each repeater, or if dynamic to be heard has to have been opened within the previous five minutes by PTT at the repeater concerned.

The repeater manager can set up a default reflector on the repeater by asking permission from the server, by self-care in BrandMeister as sysop, setting a timeout as 0 seconds for a Static connection or can set a timeout (e.g. 900 Secs) for the connection, thus making it Dynamic. This may permit a repeater to have an out-of-area reflector or an overriding connection to Talkgroup 9 on slot 2. To ascertain if a reflector is currently connected to a repeater in use, we make a private call to 5000, when the announcement on the repeater will indicate a connection or otherwise.

A repeater user can force a connection to another reflector by addressing the repeater on talkgroup 9 slot 2 by transceiver with a private call of the selected reflector, or disconnect the current connection by addressing it with a private call to 4000. The server then makes the changes to the repeater linking, subject to the rules in force on the self-care or other repeater control system in place.

To find out how to change reflectors, we can read some instructions elsewhere.

However we have to give a little advice here; whenever a hotspot user has declared that he wishes to QSY to another reflector, he must be given the opportunity to issue the private call to the new reflector, for if the channel becomes immediately occupied, he will be unable to do so.

So that wraps it up for repeaters, their slots and talkgroups and how they intersect with other repeaters via the server system.

Hotspots are systems that are in fact simplex repeaters that provide access to the world of DMR and other modes via Reflectors. Hotspots such as the DV-Mega, Open Spot, Blue DV, and the DV4Mini require the owner to address them correctly with their own DMR-ID with or without a two digit supplementary. (The DV4Mini cannot be added to in this way.) The software that interfaces the devices needs a connection to a master server either by a fixed internet or in many cases a mobile phone 3G or 4G otherwise communication over the selected network is impossible.

A user has a couple of ways to use the hotspot, but primarily needs the hotspot to have a simplex frequency programmed in the interface, and a radio similarly programmed in the CPS. My DV4Mini accepts 438.65 calls. Read further on for MMDVM Devices.

Now I have recently discovered a new way to use the DV4Mini so I will describe that secondly but firstly I will describe the easy method.

I use the DV4Mini Control Panel as adopted by K2DLS, and the firmware version 1.77 in the DV4Mini device. I will not describe how to set it up, but in my case I have to select DMR+ on the front page and a BM master server in expert setting.

Once running I can do one of three things.

I can use the group call key on the side of the MD380 / RT3 and call the reflector I require. The DV4Mini (usually) changes to the reflector. That is the easy way.

The second way is to talk directly to the software through VNC and select the reflector on the desktop application and connect. That is also an easy way but means that I have to carry around the radio and the tablet.

That was the easy method.

The more difficult method means creating further channels in the radio codeplug for the DV4Mini frequency but allocating a talkgroup to each channel. So I would have multiple channels with multiple talkgroups. I then have to set the DV4Mini to reflector 4999 – for extended talkgroups. Built into the K2DLS image is a python program, with some tables in /etc/bmxtg named buttons.conf talkgroups.conf and masters.conf. By careful study these files can be changed to contain information relevant to your region and requirements. By running the bmxtg from the desktop, you change the talkgroup accessible by the device, and you select the relevant channel in the radio with which to communicate.

The third method is to select 4999 on the DV4mini desktop, and then select selfcare on the Brandmeister pages, and select extended routing in the services menu. In the available boxes, select the DV4mini device and enter the selected talkgroup.

That is the difficult method. As I wrote, I favour the KISS principle, so this method is not simple, but proves the point of Murphy’s Rule….if someone can, someone will.

MMDVM hotspots are becoming more in vogue as the software develops. The software Pi-Star developed by Andy Taylor MW0MWZ is phenomenal. Full control over an MMDVM device by web interface is terrific. I will not go into detail on the software as it will take a whole new chapter. But I use the software for repeater control on F5ZLW that runs on a ZUM-Radio Pi-Hat. The older MMDVM repeater F5ZLR runs on an arduino system with a Pi 2 in series is controlled by SSH, which for me is very KISS.

Essential tools for DMR particularly BrandMeister include hoseline and self-care. Similar tools exist for other networks although the philosophies remain separate.

Any terms of use such as TAC, Chat, Group are purely local and may mean something completely different to users unfamiliar with their usage so be judicious in their use. You may think it makes you sound clever, but it’s not. Until a term is in general use put it to one side and make yourself clearly understood.

By all means if you have a code between friends use it but don’t expect it to be understood by everyone.

Hotspot ou Répéteur

DV4Mini USB Radio Device

Un hotspot permet un canal unique de communication entre un utilisateur et le réseau DMR BrandMeister au moyen d’un émetteur-récepteur DMR et du hotspot sur la même fréquence, et d’un seul talkgroup (TG) 9.
En utilisant les contacts numériques sur l’émetteur-récepteur ou les modifications logicielles sur le hotspot, la communication peut être dirigée vers d’autres parties du réseau en se connectant à d’autres talkgroups ou réflecteurs.

Les talkgroups sont des connexions RF qui peuvent être comparées aux canaux d’un émetteur-récepteur analogique traditionnel FM, mais c’est là que s’arrête la similitude. Ils sont en fait des connexions de base de données.

Les réflecteurs sont des connexions de données qui donnent accès aux talkgroups  respectifs qui ont été connectés aux niveaux serveurs, pour les talkgroups qui ne sont pas immédiatement adressables sur un hotspot.

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Un répéteur DMR est un système duplex, utilisant un moyen de trancher le temps d’une transmission en deux parties appelées «Slots». Chacune de ces slots sont des transpondeurs qui contiennent des informations de données que permettent à chacun d’entre eux de fonctionner indépendamment mais sur la même porteuse de radiofréquence sur l’émetteur / récepteur.

En connectant le répéteur à un serveur DMR, chacun des deux slots peut être adressé en tant que talkgroups, sous la forme de talkgroup individuel ou en multiples. Chacune des slots du répéteur est désignée d’avoir au moins un talkgroup. Les talkgroups assignés peuvent être reliés à un réflecteur sur le serveur pour assurer une connexion temporaire ou permanente.

Normalement, un répéteur sera assigné au talkgroup 9 sur les slots 1 et 2. Cette affectation permet une communication bidirectionnelle sur le répéteur au niveau purement local. Il n’y a pas de connexion au serveur ou au réflecteur à ce niveau là.

Pour une connexion au réseau plus large, un talkgroup fixe est assigné à chaque slot, qui donnent à un utilisateur la possibilité de communiquer au-delà du niveau local via un serveur vers un ou plusieurs répéteurs connectés au même TG, à condition que la radio et le répéteur auquel il est connecté,  soient configurés au même slot et au même TG. Pour plus de sécurité, un autre paramètre “couleur” est programmé au répéteur et à la radio de l’utilisateur. Au niveau du serveur, il y a un lien logiciel vers tout le système utilisant le même TG et très probablement un autre lien logiciel vers un réflecteur approprié, qui améliore la connexion entre le niveau RF et le niveau de données.

La station A qui souhaite à communiquer avec la station B dans la même localité que le répéteur, doit utiliser le même moyen, c’est-à-dire le même slot, le même talkgroup et la même couleur. Cela peut être un TG 9 sur les Slot 1 ou 2, ou l’un des autres talkgroups attribués. Cependant, ces “autres” talkgroups porteront leurs conversations sur le réseau et seront entendus par d’autres systèmes sur les mêmes talkgroups.

Par exemple, on peux voir F5ZLR le répéteur DMR-Brandmeister UHF de Limoges (tous les détails sur

Le Slot 1 porte le Talkgroup 9 pour une utilisation locale, et le Talkgroup 208 pour la connexion au Centre d’activité – France.
Le Slot 2 porte le Talkgroup 9 pour une utilisation locale, et le Talkgroup 2086 pour la connexion à la région France Atlantique.

Les utilisateurs dans la couverture du répéteur avec leurs radios programmées correctement peuvent communiquer librement sur ces Talkgroups, à une condition: s’ils souhaitent à communiquer sur le Slot 1 TG9 alors que TG208 soit actif en dehors de la zone, ils seront incapables de communiquer en raison du activité sur TG208. De même, s’ils souhaitent communiquer sur le Slot 2 TG9 alors que TG2086 soit actif, ils ne pourront pas le faire. Il y a deux slots disponibles mais 4 talkgroups. Une communication simultanée sur deux talkgroups différents au même slot n’est pas possible, ou possible seulement entre des interruptions de transmission.

Les utilisateurs qui souhaitent à utiliser d’autres talkgroups ne peuvent pas avoir la possibilité de le faire, car le responsable du répéteur n’y a peut-être pas donné accès, ou ils ne soient pas inclus dans la liste blanche. Cependant, il peut y avoir un moyen d’accéder temporairement à un autre réflecteur connecté à un autre talkgroup. En sélectionnant talkgroup 9 sur slot 2, il peut être possible d’initier un appel privé vers un numéro de réflecteur connu, en attendant une réponse vocale automatique qui dise “Connecté à …” en anglais, puis en faisant un QSO. C’est le cas sur F5ZLR. Il sera poli de terminer la connexion à la fin de la communication, en envoyant un appel privé à 4000, lorsque la réponse automatique est “non connectée” en anglais. Dans tous les cas, après 900 secondes d’inactivité, la connexion se termine par défaut. Il y a un compromis ici en utilisant ce système, il y aura un conflit avec le TG fixe 2086.

Les réflecteurs ne sont pas des Talkgroups, mais la connectivité entre eux soit attribuée au niveau du serveur. Parfois, la connectivité soit perdue, qui laissent les utilisateurs du hotspot sans communication aux niveau Talkgroups, et les utilisateurs des répéteurs sans commmunication au niveau de reflecteurs.

Dans des conditions normales, les utilisateurs se seront abonnés pour obtenir une identification numérique, ce qui permettra leur communication à réussir sur les réseaux. Quiconque ne le fait pas peut au moins trouver sa communication médiocre au mieux, et définitivement bloquée dans le pire des cas.

Dans l’esprit de radioamateurisme, on espère que toute communication sera dans les meilleures pratiques possibles.