DMR Confusion

The more I listen to DMR, the more I hear the confusion in a number 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, 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.

Talkgroups are data routings within the system of servers. A repeater manager can Whitelist or Blacklist talkgroups within the repeater thus permitting use or non-use. A standard DMR repeater will have Talkgroup 9 whitelisted and active on Slot 1 and Slot 2, which give local communication only  over the repeater. Any transmission on these talkgroups will NOT pass over the network. In technical terms these two talkgroups are Dynamic and activated by PTT only.

The repeater manager can also whitelist other talkgroups on the repeater by allocating them to a Slot. So for example in the UK Talkgroup 2350 the National centre of activity is allocated to Slot 2, however on the 5B4CY repeater in Limassol  it 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 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 this 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 5 minutes if unactivated at the repeater input.

I make a comment here that there is such a thing as repeater overload. A repeater keeper can put too many Static talkgroups on a repeater. 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 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.

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

Reflector numbers are given a relational connection to a corresponding talkgroup. 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 real bridges to other modes, and 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 for the communication to be heard on the repeater, or if dynamic to be heard has to have been opened within the previous five minutes by PTT at the repeater area.

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.

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 that reflector, or disconnect the current connection by addressing it with 4000, the private call to disconnect. 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, you can read some instructions elsewhere in these pages.

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 two 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.

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.

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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.

MMDVM Zum ver 1.0 on Arduino Dué

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 QRZ.com).

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.

Hotspot or Repeater?

A Hotspot enables a single channel of communication between a user and the DMR BrandMeister network by means of a DMR transceiver and the hotspot on the same frequency, and a single talkgroup (TG) 9.

DV4Mini USB Radio Device
By using Digital Contacts on the transceiver or software changes on the hotspot, the communication can be directed on to other parts of the network by connecting to other Talkgroups or Reflectors.
Some hotspots can be dynamically directed to Talkgroups, but hotspots like the DV4Mini generally rely on Reflectors for their connection to the network, with some interesting possibilities with 4999 the extended talkgroups reflector.
All users can register themselves on Brandmeister-Selfcare to further modify their hotspots.
Talkgroups are RF connections that can be likened to channels on a tradition FM analogue transceiver, but that is where the similarity ends. They are in fact database connections.
Reflectors are Data connections giving access to the respective Talkgroups that have been data-connected, for those talkgroups that are not immediately addressable on a hotspot.

A DMR Repeater is a duplex system, using a means of time-slicing a transmission into two parts known as slots. Each of these slots are transponders that contain data information allowing each of them to operate independently but on the same Radio Frequency carrier on the transmitter/receiver.

MMDVM Zum Board 1.0 on Arduino Dué
Zum-Radio MMDVM Pi-Hat mounted directly onto a Raspberry PI 2
By connecting the repeater to a DMR server, each of the two slots can be data-addressed as talkgroups either as single talkgroups or in multiples. Each of the slots of the repeater is designated to have at least one talkgroup. The talkgroups assigned may be linked to a reflector at the server to assure connection either temporarily or permanently. The talkgroups can be further managed by registering the repeater in Brandmeister SelfCare, so that each talkgroup can be given permanent status, rather than dynamic status activated by PTT only.
Normally a repeater will have talkgroup 9 assigned on slot 1 and slot 2. This assignment permits two-way communication on the repeater at a purely local level. There is no connection to a server or reflector at this level
For a wider network connection a fixed talkgroup is assigned to each slot, giving a user the possibility of communication beyond the local level via a server to another repeater or repeaters, provided that his radio and the repeater to which he is connecting are configured to the same slot and same talkgroup. For added security a further data parameter “colour” is programmed to the repeater and the user’s radio. At the server there is a software link to all system using the same talkgroup and quite possibly a further software link to an appropriate reflector, that enhances connection between the RF level and the Data level.
Station A wishing to communicate with Station B in the same locality as the repeater must use the same means, that is to say the same slot, the same talkgroup and the same colour. This can be talkgroup 9 on slot 1 or 2, or any of the other talkgroups that are assigned. However these “other” talkgroups will carry their conversation onto the network and be heard by any other systems on the same talkgroups.
For example we shall use F5ZLR the Limoges DMR-Brandmeister UHF repeater (full details on QRZ.com).
Slot 1 has Talkgroup (TG) 9 for local use, and Talkgroup 208 for connection to the Centre of Activity – France.
Slot 2 has Talkgroup 9 for local use, and Talkgroup 2086 for connection to the France Atlantique region.
Anyone within the coverage of the repeater with their radio programmed correctly can communicate freely on these Talkgroups, with one proviso: that if they wish to communicate on Slot 1 TG9 while TG208 is active outside the area, they will be unable to communicate due to the activity on TG208. Likewise if they wish to communicate on Slot 2 TG9 while TG2086 is active, they will be unable to do so. There are two slots available but 4 Talkgroups. Simultaneous communication on two talkgroups on the same slot is not possible, or possible only between breaks in transmission on the other active slot.
Users who want to use other talk groups may find that have no opportunity to do so, as the repeater keeper may have not given access to them, or they are not whitelisted. Some talkgroups are whitelisted for Dynamic activation, but timeout after 300 seconds. A blip on the PTT activates these talkgroups. Generally details of the available talkgroups are published on a page dedicated to the repeater concerned.
However there may be another way to access in a temporary fashion another reflector that is connected to another talk group. By selecting talkgroup 9 on slot 2 it may be possible to instigate a private call to a known reflector number, waiting for an automated voice response saying “Connected to…”, Then making a call. This is the case on F5ZLR. It is only polite to terminate the connection at the end of the communication, by sending a private call to 4000, when the automated response is”not connected”. In any case after 900 seconds of inactivity the connection is terminated by default. There is a compromise here in that by using this system, there will be conflict with the fixed talkgroup 2086.
Reflectors are not Talkgroups, but are assigned connectivity together at the server level. Occasionally the connectivity is lost, leaving the hotspot users communicating only at Reflector level, and the Repeater and Talkgroup users communicating at Talkgroup level.
Under normal conditions, users will have subscribed to obtain a Digital ID, that will enable their successful communication over the networks. Anyone failing to do this may at least find their communication poor at best, and permanently blocked in the worst case. Users of a Hotspot can enter their Digital ID + 2 further digits, to distinguish the hotspot from their own radio ID.
In the spirit of Amateur radio, it would be hoped that any communication would be in the very best possible practices.

F5ZLW – The Next DMR BrandMeister Repeater in the Limousin

With the success of the older Arduino MMDVM repeater F5ZLR, I discovered the new ZUM-Radio PI powered MMDVMHost repeater, driven by Pi-Star.

The new board arrived this week and I plugged it straight in to a new Raspberry Pi 2 with a new SD card running Pi-Star. A little tweak on the transmit pot on the board and the repeater transmitter burst into life straight away and was immediately decoded by the MD380 and the RT3. However it was taking a little more effort to ensure the decoding of received signals.

Not the best image but this is the Raspberry with the ZumRadio Pi-Hat in place. At the top of the image is the transmitter the Kenwood TK 859, and at the bottom (inverted) is the receiver an Icom GM350. The large fan will ultimately be bolted to the outside of the case to enable rapid cooling of the transmitter’s heat sink.

 

The software for the control of the MMDVMHost is the Pi-Star software written by Andy Taylor (MW0MWZ) and his collaborators.

 

The Duplexer is a Procomm 6 cavity for use in small UHF repeaters. Output is around 10 watts at present but I will probably adjust this according to results on installation.

The repeater will be installed initially alongside the F5ZGM and F5ZJE repeaters, but due to the latency of the long distance WiFi, this may prove problematic.

Transmit frequency 430.0625 MHz receive frequency 439.4625 MHz colour 1, with the following talkgroups.

On slot 1 there are TG9 and TG 208. On slot 2 there are TG9, TG 2086 and TG 2350.

Having two fairly active talkgroups on the same slot might seem a little unwise, but surprisingly unbeknownst to most users, F5ZLR was configured in this way for a whole weekend 20-23 October 2017 and appeared to have gone unnoticed. F5ZLR no longer has TG 2350 active.

Because of the proximity of F5ZLW to my QTH, I want this option, so that I can retain a degree of contact with the UK without messing with connecting reflectors. If needs must I can add another reflector via TG 9 slot 2 and QSY there.

My only concern with this configuration, is that continual activity on TG 2350 will create difficulty on slot 2 with any other chosen reflector. The UK centre of activity is focused there, but in France it’s on the TG 208 slot 1, which makes a user block less likely when QSYing to another reflector or talk group to chat.

 

Avec le succès du répéteur MMDVM à l’Arduino F5ZLR, j’ai découvert le nouveau système MMDVMHost avec ZUM-Radio PI, piloté par Pi-Star.

Le nouvelle forme est arrivée cette semaine et je l’ai branché directement sur un nouveau Raspberry Pi 2 avec une nouvelle carte SD avec le logiciel Pi-Star sous raspbian. Un petit tourne sur le potentiomètre de transmission sur le tableau et le transmetteur du répéteur marchait tout de suite et était immédiatement décodé par le Tytera MD380 et le Retevis RT3. Cependant, il fallait un peu plus d’efforts pour assurer le décodage des signaux reçus.

Ne pas la meilleure image dessus mais c’est le Raspberry avec le ZumRadio Pi-Hat en place. En haut de l’image est l’émetteur le Kenwood TK 859, et en bas (inversé) est le récepteur d’un Icom GM350. Le grand ventilateur sera finalement boulonné à l’extérieur du boîtier pour permettre un refroidissement rapide du dissipateur thermique de l’émetteur.

Le logiciel pour le contrôle de MMDVMHost est le logiciel Pi-Star écrit par Andy Taylor (MW0MWZ) et ses collaborateurs.

Le Duplexer est une cavité Procomm 6 destinée aux petits répéteurs UHF. La sortie est actuellement d’environ 10 watts mais je vais probablement ajuster cela en fonction des résultats de l’installation.

Le répéteur sera installé initialement aux côtés des répéteurs F5ZGM et F5ZJE, mais en raison de la latence du WiFi longue distance, cela peut s’avérer problématique.

Fréquence d’émission 430,0625 MHz fréquence de réception 439,4625 MHz couleur 1, avec les talk groups suivants.

Sur le slot 1, il y a TG9 et TG 208. Sur le slot 2, il y a TG9, TG 2086 et TG 2350.

Avoir deux talkgroups assez actifs sur le même slot peut sembler un peu imprudent, mais étonnamment à l’insu de la plupart des utilisateurs, F5ZLR a été configuré de cette manière pendant tout un week-end du 20 au 23 octobre 2017 et semble être passé inaperçu. F5ZLR n’a plus de TG 2350 actif.

En raison de la proximité de F5ZLW à mon QTH, je veux cette option, afin que je puisse conserver un certain degré de contact avec le Royaume-Uni sans avoir à brancher des autres réflecteurs. Si besoin je peux ajouter un autre réflecteur via TG 9 slot 2 et QSY là.

Ma seule préoccupation avec cette configuration, est que l’activité continue sur TG 2350 créera de la difficulté sur le slot 2 avec tout autre réflecteur choisi. Le centre d’activité du Royaume-Uni se concentre ici, mais en France, c’est sur le TG 208 slot 1, qui rend un bloc d’utilisateur moins probable quand QSYing à un autre réflecteur ou un autre talkgroup pour bavarder.

F5ZLR DMR-BrandMeister – Limoges (87) France

Digital Modem

Instructions for use: F5ZLR –  DMR Repeater

Digital Mobile Radio – BrandMeister

Transmission 430.075 MHz – Reception      439.475 MHz

Colour code 1

Slot 1 talkgroups TG9, TG208

Slot 2 talkgroups TG9, TG2086, TG20887

  1. The repeater has effectively two channels (slots) available at any one time. If both the slots are active, the possibilities are communication exist only in breaks between the activity on a selected slot.
  2. In each slot there are a fixed number of Talkgroups, so that activity can be divided into the available different groups. Talkgroup 9 is local to the repeater, and the rest are channelled through Brandmeister servers to the connected groups. 208 is France National, 2086 is Atlantic region. There are other talkgroups available through Reflectors in the supplementary paragraph below. Certain talkgroups are available only on slot 1, while others are found on slot Talkgroup 9 is the exception where it is found on both slots, but do not connect to each other.
  3. Normally we would begin our conversation on the centre of activity, which in France is Talkgroup 208. On making a contact here, we would normally advise a QSY to a chat channel which in our case would be Talkgroup 2086 – Atlantic.
  4. If your correspondent is on the same repeater, you can both QSY to TG 9 slot 1 and continue to talk. However if Talkgroup 208 continues to be active you can go to slot 2 Talkgroup 9 instead as slot 1 remains occupied. However paragraph 1 applies.
  5. If an alternative talkgroup is suggested, using a group call on Talkgroup 9 Slot 2 to another reflector in the chart below is a possibility. For how to make group calls see the instruction manual of your radio.
  6. At the end of any group call activity please make a group call to 4000 to receive “Not connected”, thus to make free the repeater for other calls.
  7. To test your transceiver on the repeater, you can make a private call to 9990 at the same moment as you speak to receive a reflection of your call as you release the transmitter key.
  8. There two types of Talkgroups: Fixed and Dynamic. The talkgroups listed above are fixed and made available in permanent transmit on F5ZLR. However behind the scenes there are the dynamic talkgroups that are user activated. These talkgroups require a short blip on the PTT to activate them, and they remain active for 5 minutes only. On slot 1 the talkgroup 937 (Francophone WorldWide) is available, and on slot 2 UK Talkgroups 2350 (UK wide), 2353 (UK Wide Chat), and 23887 (France bridge to C4FM).

All BrandMeister reflectors (click on the link)

and how to use them

http://www.gb7dd.co.uk/wp-content/uploads/2016/02/Using-BrandMeister-Reflectors.pdf

Technical data:

Transceiver pair – Motorola GM 350 4 channel models. Internally modified to give flat audio in and out to the accessory socket on the rear. For details of how this is achieved there are various resources on line.

Accessory socket links are as follows. 2. Tx Audio, 3. PTT, 7. Ground, 10. +12v in, 11. Rx Audio.

Arduino Due (pronounced doo-ay as it is Italian) is compiled in Windows from source on the github/g4klx. Again the information about this is well documented.

The Due is connected to the Raspberry PI 2, in our my case with Ubuntu Mate 16.04.02 as the operating system, with the MMDVMHost software and .ini file compiled within.

The Due is completed with ZUM 1.0 board with on-board txco, connected to the transceivers. The repeater is finished with a repurposed AX25 power pack into a case for the 19″ rack. Because of the expected high duty cycle a 220v fast fan has been employed across the whole interior keeping everything cool. The duplexer is 8 cavity Katherein model tuned giving less than 1db in losses, which is good. Consequently the transmitter send 8 watts to the dual band antenna. It was original intended to share this antenna with a remote receiver for the existing R2 VHF repeater 40 Kms away, but the diplexer permitting the UHF and VHF systems to share was deemed too lossy, so the remote receiver has been turned off for the time being, leaving the repeater to run perfectly.

Code plugs for Tytera MD380/390 and Retevis RT3 or similar.

I have seen many requests for code plugs to be shared but to be frank there is nothing better than learning to do it yourself.

Both these radios are similar, but I find that there IS a slight difference between my RT3 and the MD380G due to the different vocoders and the addition of the GPS. The software for each is incompatible with the other and will display a warning to that effect.

We can run the software initially without the connection of the radio and build the code plug piece by piece, researching the various aspects as we go and saving it from time to time.

Absolutely essential will be the digital ID (so if you haven’t got it, do it now as you cannot use the radio successfully until you have).

Let’s start the CPS. It should be blank and show the content of the first menu Basic Information.

Select your frequency range, I’m starting of in the 400-480 MHz range, and I fill in all the boxes that the software can permit.

Let’s go to General Settings, giving the radio a name and entering the Digital ID in the Radio ID box. In Alert Tone, I would suggest selecting Digital in the Talk Permit Tone, so that any repeater correctly accessed will cause our radio to respond with “bleepity bloop” if it is good to go.

I left everything else as standard except the Intro Screen where one can select Char String, and have two friendly lines of texts greet the user when switched on. I have chosen my two call signs. ** See a note at the bottom regarding “unknown, unknown”.

Let’s pass straight on to Button Definitions.

I would suggest short press on side button 2 to Manual Dial for Private and long press toggle High/Low Power.

That leaves us button 1 to do with what other function is deemed necessary.

Now we’ll go to Digital Contacts.

It is important here to try and get some semblance of order. The contact name will be the convention used by the general amateur populace. I have stuck to what is “normal”, such as TG9 for talk group 9, or whatever might be practical, however the Call ID MUST be the numerical value of the talk group or reflector that is referenced to it. I chose to enter all of the available talk groups wherever they may be, in numerical order as Group Calls, followed by all of the available reflectors as Private Calls, but then I can add any other Digital IDs as Private Calls, together with names and call signs as needed, but with Talk Alias and the .csv database in MD380Tools, this may not be always necessary. We may not think we need all the talk groups or reflectors but it is best to add them now as it makes for a tidy code plug database later, we may not use all of them, but they are there for future use. The Call Receive Tone is at the users discretion.

We can safely skip the rest of the menus for the moment and go straight to Channel Information.

Here is where our research is most important. For each repeater or hot-spot, we will need to know the frequencies and the colour code, together with the talk groups that are available on each of the repeaters and on which slots they are.

So for example F5ZLR has its TX frequency 430.075 MHz and RX frequency 439.475 MHz. Colour code 1. There appear to be 4 operational talk groups TG9 Slot1, TG208 Slot1, TG9 Slot2 and TG2086 on Slot2. So this means we will be creating 4 pages in Channel Information, so we will need to give each page a Channel Name, carefully selecting each of the drop down boxes. Digital in Channel Mode, Color code in Admit Criteria, RX ref and TX Ref as low, TOT (timeout timer) to whatever we prefer. Contact Name will be the Talk group, from our previously constructed table. Color Code and Repeater Slot are from the conducted research.

Click Add and we will have saved our first page and created a new blank page. Now for the time saver!

Click on the page we have already created in the menu list on the left, and right click Copy. We highlight the new page in the list, also in the menu, and click paste. In the new main page on the right we just need to create the Channel Name, select the new Contact Name, and Slot number. And repeat!

So as I have said for F5ZLR we create four channels for the two slots each with two talk groups.

Next we go back up the menu list to Zone Information where we create a new zone and give it a name. This zone can contain up to the 16 positions on the channel switch, but for the moment we have only four channels programmed. From the available channels list on the left we can add channel members to the right side.

In my case I have created many more channels that I would consider of use, like DMR simplex or PMR channels, so I can fill a zone of 16 channels so I don’t get the horrible squawk of a vacant un-programmed channel.

Some repeaters may have more than 16 available talk groups, so you can create more than one zone, like one containing all slot 1 channels and the other with slot 2. But why any repeater keeper would add more than two talk groups is beyond my comprehension, or more than one mode for that matter. Such potential for over-population of a slot will cause blocking on talk groups that may have use of that slot.

As we build the CPS we must do frequent saves, so that if we have to go back we haven’t got to build it from scratch – again. I know you’ve done – I did it, so you must have done it too!

Then we upload the code plug to the radio. It’s that easy.

F5ZLR is an MMDVMHost based DMR-Brandmeister Full-Repeater located in the City of Limoges (87), running two Motorola GM350 Transceivers, interfaced by a zum board to an Arduino Dué Computer controlled by MMDVMHost running on a Raspberry Pi 2 with Ubuntu Mate 16.04.1.

Talk Group 9 and Talk Group 208 (French centre of activity) are on slot 1, and Talk Group 9 and Talk Group 2086 (Region Atlantique) are on slot 2. Initiated QSO’s on 208 can QSY to 2086, and subsequently not interfere with future use of 208. However visitors to Limoges are not limited to these groups as a UK visitor to the area can initiate a group call to 4400 on TG9 slot 2, wait for the parrot to confirm the connection and then have a QSO with friends in the UK, subject to the proviso that 2086 on the same slot does not become active in the meantime. 900 seconds of inactivity resets TG9 closing the connected reflector. Good practice suggests a group call to 4000 to disconnect when a QSO is finished.

Finally as one who uses MD380Tools and regularly updates the .csv, it is a good idea to have “Promiscuous” mode active around a repeater, so you can see the activity before making your talk group selection. Turn it off as you go to QSO otherwise you will get interrupted but unwanted chatter.

If you are running MD380Tools, be aware of a problem that prevents the display of your name and call sign on switch-on. If you find that you get “unknown, unknown” in the window if you had selected text display, then you need to go to the menu as follows: Utilities, MD380Tools, Developer, CoPl override, and click to disable. Turn off the radio and turn it on again, and hopefully all will be well again.

If you don’t get this menu selection, then you will need to update your MD380/390 RT3 from MD380.org following the links to daily update to get the latest version including the updated .csv of DMR IDs.

Also if you like a tidy database you can always locate and download a useful utility ContactManagerV240.exe that can sort everything in the database into AlphaNumerical order.

All BrandMeister reflectors (click on the link) and how to use them.

http://www.gb7dd.co.uk/wp-content/uploads/2016/02/Using-BrandMeister-Reflectors.pdf

F5ZLR Répéteur – DMR Brandmeister

 

F5ZLR – Répéteur DMR BrandMeister

Limoges (Beaubreuil)

    DigitalMobileRadio   – BrandMeister

Ce répéteur était construit par le technicièn Christopher Jackson F5VMR. Situé à Beaubriuel au nord de Limoges, il donne une couverture de bonne distance autour de la cité, même aux bon points hauts à distance de 45kms.

Deux transceivers Motorola GM350 forment la partie transmission/récéption

Digital Modem Zum Board sur Arduino Dué

de ce répéteur numérique. L’interface ZUM v 1.0 est montée sur un ordinateur Arduino Dué, programmé avec le logiciel MMDVM (Multi Mode Digital Voice Modem) crée par Jonathan G4KLX. Un Raspberry Pi 2 avec l’O.S. Ubuntu Mate fait le réglage du modem avec MMDVMHost.

 

Zone de couverture approximative

Plutôt la disponibilité des autres modes numériques sur ce système là, le seule mode en marche est le mode DMR avec la connexion au réseau BrandMeister. Ce réseau donne tous necessaire pour la bonne fonctionnement du relais.

Il n’y a pas de fioritures comme les écrans LCD. Qui va regarder dans une pièce fermée pour voir ce qui se passe? Tout est à la radio sur l’aire! Le répéteur est télécommandé by SSH.

Transmission: 430.075 MHz  Réception: 439.475 MHz 

Code de couleur 1

Slot 1 TG9, TG208

Slot 2 TG9, TG2086

  1. Le répéteur a effectivement deux canaux (on dit “slots”) disponibles à tout moment. Si les deux slots sont déjà actives, que les possibilités soient  la communication n’existera qu’entre les ruptures de l’activité sur un slot sélectionné – en break.
  2. Dans chaque slot, il existe un nombre de “talkgroups fixes ”, où l’activité peut être divisée en différents groupes disponibles. Le  talkgroup 9 est local au répéteur, et les restes soient acheminés par les serveurs BrandMeister aux groupes connectés. 208 est la France National, 2086 est la région de l’Atlantique. Ils existent d’autres talkgroups disponibles dans les réflecteurs dans le paragraphe complémentaire ci-dessous. Certains talkgroups sont disponibles uniquement sur le slot 1, tandis que d’autres sont trouvés sur le slot 2. Le talkgroup 9 est l’exception où il se trouve sur les deux slots, mais ils  se ne connectent pas ensemble. Vu en haut de la page.
  3. Normalement, on commence notre conversation sur le centre d’activité, en France, c’est le talkgroup 208. En établissant un contact ici, on conseille normalement un QSY à un autre talkgroup qui, dans notre cas, serait le talkgroup 2086 – Atlantique. (En Royaume-Uni centre d’activité est slot 2 – 2350, mais activité Nationale slot 1 – 235). Ceux-ci sont talkgroups fixes.
  4. Il y a des autres talkgroups dynamiques 2350, 2352 (de Royaume Uni) et 20887 tous  supplémentaires sur Slot 2 qui soient disponible sur un clin de PTT, et le dernier qui soit connecté au pont de YSF – C4FM – fusion. 
  5. Si notre correspondant est sur le même répéteur, on peut à la fois QSY à TG 9 slot 1 et on continue à parler. Toutefois, si le Groupe 208 continue d’être actif alors que le slot 1 reste occupé, on doit accéder au Slot 2 Talkgroup 9. Mais s’il y a déjà l’activité sur slot 2 toutefois, le paragraphe 1 s’applique.
  6. Si un talkgroup alternatif soit suggéré, il est possible d’utiliser un group-call sur Talkgroup 9 Slot 2 sur un autre réflecteur dans le tableau ci-dessous. Pour savoir comment faire des appels en groupe, on consulte le mode d’emploi de notre radio.
  7. À la fin de toute activité d’appel en groupe, on doit faire un appel en groupe à 4000 pour recevoir “Not connected”, afin de libérer le répéteur pour d’autres appels. En tous cas le réflecteur se ferme après 900 secondes.
  8. Pour tester un émetteur-récepteur sur le répéteur, on peut faire un appel en groupe 9990 au même moment qu’on parle pour recevoir une reflet de l’appel lorsqu’on relâche la clé de l’émetteur.

Bon Trafique

Chris F5VMR

TalkGroup Réflecteur Description
208 4300 France entière
2080 4310 France Ile-De-France
2081 4301 France Méditerranée
2082 4302 France Alpes
2083 4303 France Midi Pyrénées
2084 4304 France Est
2085 4305 France Ouest
2086 4306 France Atlantique
2087 4307 France Nord
2088 4308 France Centre
2089 4309 France Dom-Tom
937 4837 Francophonie (français international)
20811 4311 YSF-France.fr
20812 4312 France SVXlinkfr (info à compléter)
20813 4313 France – Passerelle D-Star XRF270 B
20817 4317 France – Passerelle D-Star XRF208 S
20818 4318 France – Passerelle D-Star XRF929 D
20820 4320 France – Urgence Francophone
20821 France – Corse (Corsica)
20859 France Lille Local