A new TETRA project in the Brandmeister Family

Artöm DL5ABM and his team are thrilled to present their newest endeavor TetraPack.Online, a Tetra TMO amateur radio network showcased for the first time at HamRadio 2023 in Friedrichshafen. This project shares common objectives with Brandmeister, such as multiple hardware support, widely available talkgroups and digital services.

What is Tetra, how is it different than DMR ?

Tetra is also a digital radio protocol leveraging the concept of talkgroups and timeslots, with a few improvements amongst which:

  • Tetra uses a different codec (ACELP) offering superior voice quality compared to DMR or P25,
  • The TetraPack RF protocol allows for 4 timeslots over a 25kHz spectrum. One timeslot is dedicated for signaling (data exchange between the subscriber radio and the network), while the remaining 3 timeslots can carry simultaneous voice conversations. If you want, you can stack more base radios and get an additional 4 timeslots for each frequency added while still needing only one signaling timeslot!
  • It is possible to have full-duplex conversations, so your radio behaves like a cellular phone,
  • The concepts of static and dynamic talkgroups are gone. Once you select your desired talkgroup on your radio, there is no need to press PTT. Your radio automatically communicates your chosen talkgroups to the network and an a voice timeslot will be allocated for you to listen and talk through.
  • Basic web-based browsing is possible (comparable to WAP)

How does TetraPack.online integrate with Brandmeister.network ?

The two networks tightly integrate with one-another:

  • The same IDs assigned by RadioID.net are used on both networks to identify ham callsigns,
  • All talkgroups greater than 90 are shared with both networks,
  • Group calls and private calls are supported within and across both networks,
  • SMS can seamlessly traverse between the two networks.

What do I need to setup a Tetra Base Station?

In the Tetra world the terminology has evolved from “Repeater” to “Base station”. This configuration comprises a Site Controller responsible for network-side functions, and a Base Radio which divides the 25kHz carrier into 4 timeslots. Several base radios can be added into one Base Station (each using their own frequencies) thus providing more timeslots. You could almost compare this to a DMR Tier 3 setup.

Presently, TetraPack only supports two Motorola hardware platforms because they are the only ones we have been able to acquire and develop on at this point. If you, or someone you know, can lend or donate alternative Tetra hardware to our development team, we will work on incorporating support for the new equipment. We also welcome donations to help us purchase diverse Tetra hardware and expand the range of supported platforms.

At the moment, we have tested and built support for the below configurations:

Configuration Option 1

Configuration Option 2

  • Motorola EBTS or MBTS base station
  • PC or Raspberry running Debian 64-bit
  • icE1usb E1 adapter, or Cisco 2611XM router with either the vwic2-1mft-t1/e1 or vwic2-2mft-t1/e1 module.

Once you are ready to start, contact an administrator on the Tetrapack Telegram Support Group to get connected!

Which Tetra radio to use ? How to program it ?

You can use any TMO-compatible Tetra radio to communicate on the TetraPack network.

Just like DMR, the radios are programmed via codeplugs. However you only need to enter base station frequencies and talkgroups; the timeslots are dynamically assigned by the base station.

Can you connect using a hotspot ?

We are not aware of any hotspots supporting Tetra at this point.

Resources

More information can be found below: