Exploring Digital Communication: Joining Our Weekly Club Net- Grantham Link

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The following has been written with beginners and newcomers to digital communication in mind, and it's not intended to come across as patronising for those who are more experienced in amateur and digital radio.


Over the past couple of club meetings, there has been a discussion about holding a club net on Tuesdays, in addition to our regular meeting.

Connecting through GB7GR:

We will be using GB7GR digital repeater as the central point of contact for the club net. Keeping this in mind, it’s important to note that not everyone might be familiar with digital communication, even though we may own radios with this feature.
So, for members new to the club and hobby, think of a digital repeater like a relay station that boosts our radios communicate over a larger area. GB7GR can handle different digital communication modes like DMR, Yaesu Fusion, and D-STAR, but only one mode at a time.

Joining the Net with Different Radios:

However, if I connected to GB7GR using my DMR handheld radio and picked a specific communication channel called “Talk Group 9”. Which is a local TG, that just relays my signal out again. If I did this, only people with DMR radios who could connect direct to GB7GR will be able to join the net. This means not all club members could participate because they might have a different type of digital radio or signal strength make it not possible to connect to the repeater.

Introducing the Freestar Network

Now, things might get a bit more complex, so bear with me. GB7GR, a digital repeater, is also connected to the “Freestar” network through the internet. Think of Freestar as a hub/interconnect where different repeaters and hotspots can connect. There are similar systems like “Brandmeister” too.

Talk Groups: Digital Radio’s Chat Rooms

Here’s the simplified part but not necessarily technically correct: Freestar has something called “Talk Groups.” Think of these like internet chat rooms, but for our radios. Just like we have different chat rooms for different topics, we have different Talk Groups for different things on our radios. Yaesu Fusion use something similar called “WiresX Rooms,” and they’re also known as “Reflectors.” on other systems.

So, in simple terms:

Talk Groups (TG) = WiresX Rooms = Reflectors


* For clarity. There are other digital systems not mentioned here.


Club Net Hosted on Talk Group 853

Now, GB7GR has its own specific and static Talk Group 853 (Grantham Link), which is perfect for hosting our net. Because this Talk Group is available in the cloud, anyone with a DMR radio can connect to it from a digital repeater, a gateway, or their own hotspot device.

This works well for those who can’t reach GB7GR directly. They can use their hotspot or a local repeater to connect to Talk Group 853 and join the net.

Introducing Bridging – cross mode

However, we also have members with Yaesu Fusion and D-STAR radios, which employ a different digital communication system. To make things work for them, we use something known as a “Bridge.” Some clever Radio Amateurs have developed hardware / software bridges that link these radio systems together. Currently, the easiest approach involves using a hotspot device. With my hotspot, for instance, I’m able to establish a connection to the clubs Yaesu Fusion Reflector (G0GRC) from my Yaesu 991A, that’s bridged to TG 853. This way, members with DMR and Yaesu Fusion radios can talk to each other on the same Talk Group during the net.

This also will also apply to D-STAR, although there is no bridge set up yet!

Participation: What You Need

In essence, all club members equipped with DMR, Yaesu Fusion, or potentially D-STAR radios can join the net discussions if they have access to either:

– Direct RF connection to GB7GR (or other connected repeater / gateway)
– Hotspot Device: DMR / Yaesu Fusion / D-STAR

Configuration Guide for Your Radio

If you’d like to join the Grantham net, you’ll find some settings and configurations listed below as a guide to help you in setting up your radio.


Configure a channel on your DMR radio your radio with the following

For Direct RF access to GB7GR using DMR

Channel Name: Grantham Link (or name of your choice)
RX Frequency: 439.45000
TX Frequency:
Channel Type: D-Digital
Color Code: 5


If you are using DMR from your hotspot

Channel Name: HS Grantham Link (or name of your choice)
RX Frequency: Freq of Hotspot
TX Frequency:
Freq of Hotspot
Channel Type: D-Digital
Color Code: 1


For Fusion

Specific settings for Yaesu Fusion can be configured in the Pi-Star software on your hotspot,

MMDVMHost Configuration

Enable YSF Mode

Yaesu System Fusion Configuration

YSF Startup Host: YSF21982 – GB-G0GRC – garc.org.uk
UPPERCASE Hostfiles: Enable if you have a FT70D
WiresX Passthrough: Enable
DMR Master: DMR+_IPSC-Freestar or FreeSTAR_UnitedKingdom



Currently, a bridge is not set up for D-STAR, but stay tuned for updates!



Whether you’re a DMR, Yaesu Fusion, or D-STAR enthusiast we look forward to welcome all club members to our weekly net. (TBC)

73 M5DJC – MarkC



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