All about GB7LN

This UHF DMR repeater located in the City of Lincoln has been on air for a number of years now, but has never had more than a small handful of users as Lincolnshire doesn’t seem to have embraced digital modes quite as much as other areas. Users who are interested, tend to set up their own hotspots these days, further lessening the user base of public repeaters.

GB7LN is part of the Brandmeister network, (repeater 235199) and as you would expect, it connects with all other repeaters in the same network all over the world. It transmits on 439.400 MHz and receives on 430.400 Mhz, and uses cc 1

There are two timeslots on the repeater, slot 1 and slot 2, both on the same frequency, and users can have a conversation on either slot at the same time.

Slot 1 on GB7LN has always had static talkgroups 91 for worldwide, and 505 for Australia, and I will be keeping those for the time being.

Slot 2 has been where something called the reflector used to live, and users could access other groups and areas by dialing in a number on Slot 2 and working via the reflector.

By the end of 2020 however, the reflector in the UK is being turned off, after which we will need to use “dynamic talkgroups” instead, and may mean that you need to reprogram your radio for it to work correctly. Below is a map of the UK showing what the national and regional talkgroup numbers are on the Brandmeister network, that you need to use for different areas.

At the moment there are no static talkgroups on slot 2, although I may add 23590, the East Midlands talkgroup if users think it would be a good idea.

Users can currently use Talkgroup 9, slot 2, as a local chat channel, but it is worth checking first that a dynamic talkgroup is not still connected, by transmitting for 2 seconds a Private call on TG4000. Talkgroup 9 does not repeat to the network if a dynamic talkgroup is not connected. In essence it acts like an analogue repeater and just transmits locally.

How to program your set to work with dynamic talkgroups via TG9 on Slot 2.


One way, and perhaps the easiest to use the Dynamic talk groups is to program the radio with TG 9 on Time Slot 2.
To do this make a new GROUP call and allocate number 9 as the contact number.

Make a new channel up for TG9 on slot 2 and add that channel to the zone for the repeater in question.
This is the only Talk group you will need for a QSO on the dynamic talk groups.


To link and unlink the Dynamic Talk Groups.
Do a Manual Dial –
Menu – Contact – Manual Dial – enter Talk group number you wish to connect to and transmit for 1 second.
or
Menu – Talk Group – Manual Dial – enter Talk group number you wish to connect to and transmit for 1 second.
The repeater will respond with a voice announcement, “Linked to 2350”.
You can then go back to Talk Group 9 to make a QSO on the talkgroup you entered, because as TG9 is only local, it uses the dynamic talk group you just activated to work through.
or
Program the radio with the Talk Groups as Private Call in contacts.
To link to a Dynamic Talk Group.
Select the Talk Group number from the contacts list and transmit for about 1 second.
Then go back to Talk Group 9 to make a QSO as before.

To Unlink
Manual Dial 4000 Private Call transmit for about 1 second,
The repeater will respond with a voice announcement, “Not Linked”.


Get Status
To enquire about the Talk Group linked Manual Dial 5000 Private Call, and the repeater will
respond with the currently linked Talk Group.


Echo/Parrot
Manual Dial 9990 Private Call, and the Echo/Parrot will respond back to you only.


You will need to program the Hang Time for Private Call in your code plug for around 3 to 5 seconds.
This will drop the radio from Private Call back to Group Call for Channel TG9

If anyone needs help in programming a code plug for either a Motorola or Retevis radio for GB7LN, please get in touch and I will be happy to help you.