Short Write-up on how Private Groups work

Programming contacts and groups into the DTR radios seems simple enough, but when they don’t work as expected, it’s quite difficult to figure out what’s going wrong.
I spent some time today to experiment with Contacts and Groups to see if I could figure out what the logic was and how they worked. I may or may not have this right, but going forward, what I have learned will help me to make sure things keep working properly when programming.

If you always use the normal method of programming, by programming one radio completely and then cloning all the others to that radio, you shouldn’t run into many issues. It’s when you start doing individual programming on single radios and don’t update all the radios to match is where things can get weird. In my use of the radios, I’m constantly updating individual radios as getting them all back to do mass programming or cloning is simply not possible when they’re all in use. Over-The-Air (OTA) cloning helps, but not always.

The biggest thing I’ve learned and is important to remember is that names mean nothing on the radios. It’s the ID numbers that matter. IDs are used for all Contacts, whether they be Privates or or Groups (Private or Public). Keeping that in mind, I can create a private contact called “Prvt 1” on Radio A, and enter the ID of Radio B into that contact. Or Read the ID from Radio B when creating the contact on Radio A and then change the name, and it will always call that same radio. The name that appears on Radio A will be whatever name I gave that radio when I edited the contact ON RADIO A, not the name that Radio B has for itself. Same goes for Groups. The names can be different on different radios, it’s the ID numbers that mean everything.

Here’s what seems to happen when you select a contact and press the PTT:
If it’s a Private Contact , it sends out the ID of that contact, and if a Radio matching that ID is powered on, the receiving radio will send back to the transmitting radio an acknowledgement, beep twice and the transmitting radio will allow you to speak to the receiving radio. If no radio has that matching ID, then you will get the long beep and “User Not Available” message on the transmitting radio.

If it’s a Private Group , it again sends out the ID of that contact, and if a powered on Radio that has a Private group in it’s contacts with the matching ID, it looks to see if it’s own ID is listed as one of the members. If it is, it sends and acknowledgement back to the transmitting radio and you can speak to the receiving radio. Also, if a receiving radio happens to be currently “on” that particular group, (with the matching ID), even if the receiving radio is NOT a member of that group, it will receive the call.
What’s important to note here, is the members of the group listed on the transmitting Radio are irrelevant. It’s the ID that’s important. The RECEIVING Radio is the one that checks it’s members list to see if it’s part of the group and if it is, receives the call.
Again, if the contacts are the same on all radios, including group IDs and Members, things will always match and there’s no issues.

If you decide to do an OTA “Remote Add” of a contact to members of a private group, then the group members listed on the source radio (the radio initiating the OTA programming) will come into effect. Only radios that are members of the group you are sending the “Remote Add” to will receive the contact info.

All this info can be a little confusing, so try as much as possible to have matching contacts and groups on all radios rather than changing them individually on each radio. If you do have to change them on a radio, make sure you at least do an OTA Remote Add to all the other radios to update them and keep everything in sync.

Hopefully this information helps when doing any complex programming on individual radios!

Feel free to comment!

@Andy - These links are all broken on new forum Software - are your Blog Posts on the DTRs still available somewhere?

I’ve searched and can’t find them.

Thanks for sharing all this DTR info though! This is the only place online with this info.

1 Like

Thanks for letting me know.
Copy/Pasted the info here.