Also known as DMR Group Calls, you can talk on them, they can route traffic and control the network activities. Talkgroups are can become more complex quickly. If you wish to understand the how and why of PNWDigital networking operations, read on.

The number of talkgroups available to users may appear to be overwhelming, unnecessary and/or confusing, especially to new DMR users. On the other hand, if you are an experienced Brandmeister user, you may not be happy with the paltry selection of talkgroups available on our c-Bridge based DMR network. This page will attempt to explain the what, why and how of talkgroups and how they are integrated into our PNWDigital.Net network. This page is aimed to assist new users of the PNWDigital.Net network for a smoother entry and rise up the steep slope into the Ham DMR world.

Talkgroups are very simple at their core. You typically talk on it and it does all the control, it links repeaters, networks and the world. They also unlink traffic, hold-off traffic so that your QSO is not interrupted and essentially are the network traffic cops so that you do not need to be. If you want yet more on how PTT works with talkgroups, as well as how they control the network under the hood, then grab a soda and get comfortable with PTT.

Talkgroups are similar to CTCSS, DCS and Touch Tone on a FM analog repeater but rolled into a single function…and you can talk on it it too. So Talk + Group. It is all done on the backend so that you simply choose the talkgroup and it does all the heavy lifting for you. The names of the talkgroup generally provide a clue as to it’s purpose. Say Local 1 vs Worldwide 2 for example. Local 1 is linked only to a single repeater and it resides on timeslot 1. Worldwide 2, is on timeslot 2 and it links to hundreds of repeaters around the world. You don’t need to know how to do it, you just select it. This is a simple look but it really is not much more complicated than that for the user.

Talkgroups have 2 primary states. They are known variously as Always Active / FT / Full Time. The other complementary state is PTT / Part Time Talkgroups / Push-to-Talk. FT talkgroups will always be heard on a repeater if the repeater’s timeslot is not otherwise busy with another talkgroup. You will not normally hear traffic on PTT talkgroups unless you kerchunk that talkgroup to energize it. A kerchunk or ongoing conversation will activate and/or renew a timer, generally for 15 minutes of listening time from the last local user’s transmission (check Netwatch).

If you are looking for activity, especially from outside our region, you may need to hit the pickle to hear more activity. If you are wondering if your radio/repeater/network is working, just test on the Parrot talkgroup, you should hear your transmission echoed back. This is also a good method to test for audio quality and also an excellent method to quickly determine that the repeater and network are working properly.

Timeslot 1 typically carry our primary talkgroups and they are FT talkgroups. This includes most or our statewide talkgroups as well as some regional talkgroups. Almost all timeslot 1 talkgroups are our own homegrown and PNWDigital controls them near exclusively. Timeslot 2 talkgroups are more auxiliary, redundant and other network talkgroups that we wish to carry on our own network. These talkgroups tent to be more on PTT. So calling or hailing within our network is done on timeslot 1 while timeslot 2 is more open for QSO’s with those outside of our network.

The talkgroups page provides more detail about our talkgroups and is a good guide selecting talkgroups to try out. The details are not hard rules but meant to help users understand the basic talkgroup use structure. But sans more experience on PNW, we urge you to become familiar with these details. Some networks operate their talkgroups that they share with us, so it is good to understand any operational differences before you hope onto those outside talkgroups.

Next is a tip. If you are looking for a general contact, you might do more than just say your call sign. Try something to stimulate a response. If you are testing or want a demonstration, please say so. Many hams may be listening but otherwise occupied or scanning, so just saying your call sign may fall short of getting a response. This is loosely similar to the Friendly Repeater phenomenon. It is always good operating procedure to allow 2 to 3 seconds between transmissions during a conversation to allow for users to break in or to kerchunk out (disconnect) from the talkgroup. That can’t be done while any user is transmitting on an active talkgroup but can only be done during that narrow window between transmissions. Therefore, NO QUICK KEYING please!!!

To determine which talkgroups are available on which repeater, please check out our Talkgroup Viewer. The viewer is also matched to our community codeplugs so that each zone has only channels with those supported talkgroups.

We also have a numbers of Talkgroup Matrices which are grouped with similar area repeaters. This can help you find a close repeater that might have the talkgroup that you would like to use.

MCT’s (Master Control Talkgroups) are more advanced controls for talkgroups and taking on more importance as the list of talkgroups continues to expand. These are specialized talkgroups that control other talkgroups. While not a beginner topic, you should become more familiar with their purpose and advantages.

The c-Bridge (our network gateway device) manages everything discussed above. It recognizes all legitimate (authorized) talkgroups and acts upon a set of criteria mapped/programmed into the device and that is collectively accomplishes the intended task(s). The main task is to route the voice calls to the correct repeaters but now you have some idea of the other important tasks happening in the background such as setting timers and switching other other talkgroups on or off.

First Published: September 27, 2021 Last Updated: 2 years ago by Mike – NO7RF

Views: 375

Leave a Reply