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.
1. 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. Talkgroups are Group Calls but Reflectors and Personal contacts are registered as Private Calls. In the Tytera and Retevis CPS you can clearly see the numbering is unique for each group. When creating a named Talkgroup 9 for example, it should appear in the table as 9 in the associated group call list, or it won’t work. I know; I mistakenly one time only programmed TG 9 and found it didn’t work, only to find that TG9 on the screen was talking on TG 4.
2. When creating your frequency lists, research each repeater and hotspot and look for the norms, that is to say determine on which slot certain talkgroups should be active. A simplex hotspot isn’t a problem, as normally TG9 is norm. This is not restrictive practice, it’s just common sense. In most cases talkgroup 9 should be found on both slots of a repeater, possibly talkgroup 10 and talkgroup 99 as well. Every available talkgroup on each repeater or hotspot needs to be programmed individually. Consider programming in simplex channels as well. There are channels available for DMR simplex, and PMR/DMR as well. Why not add them while you are at it.
3. Zone choices are a lot more difficult to make. On each named zone you can fill 16 channels with information preprogrammed in the first and second categories. You can have more than one zone to cover a repeater, its talkgroups and its slots, and mix a selected zone with adjacent repeaters if you want for an easy change of channel.
When considering the three factors above look at the following information when talking either on a hotspot or your local repeater.
On slot 1 normally single digit, double digit and triple digit talkgroups are standard. Slot 1 should normally contain international, national and language based talkgroups. But this is not always the case. Check your repeater’s home page.
On slot 2 are generally found 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. Again check your repeater’s home page.
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 or Static talkgroups are those that are locked open 24/7 or by schedule, by activating this function on selfcare, or by the functionality of PiStar software, or forced by MMDVM changes.
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 with other locally grouped repeaters.
This means 2350-2354 are either dynamic or fixed (static) on slot 2. 80,81,90,91,235 etc are dynamic or fixed (static) 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 except by a group call to TG4000 on the system in use, it kills all dynamic talkgroups, but reflectors do not time-out, but they can be disconnected by private call to Reflector 4000. I say they can’t time-out, but a sysop can force a time-out in selfcare. What I have noticed however is that a dynamic talkgroup called up by a user can supplant one called earlier. Talkgroup 9 should not be a static talkgroup, but left dynamic. It is what it is, local and PTT operated. Planting a reflector on it changes its nature, and takes on the characteristic of the talkgroups in the reflector. As it has been connected locally there really is no need to leave it connected when it has finished it’s task.
As I see it Mmdvmhost, as in most homebrew repeaters like F5ZLR and GB7SO have all talkgroups unrestricted, which can create 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 (make static) 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. It is not socially acceptable.
By removing this command, the repeater reverts to fully open as standard. There are methods to do this in pi-star but does not appear to be well documented.
Remember there are only two available “channels” and we all have to share. As I see it if a dual mode is operating D-star on one slot then DMR is NOT available on the other.
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 a codeplug.
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.
TG23522 is a bridge to Wires-x and TG23526 is a bridge to the AllStar hub.
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 off 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. By all means enjoy it but do consider others. Any opinions expressed are mine.
Regards, Chris F5VMR G4NAB.