What are User Activated Talk Groups
These talk groups can not be heard under normal circumstances. They require the user to press the PTT in order to activate them thus they are considered as alternatives for wide area talk groups as they are only active on the repeaters of each user. The only way you will hear conversations on of these talk groups is if someone else has activated it on the repeater you are listening to.
How do you use them – Best Practice – Revised August 2017
Since the recent migration of Phoenix servers away from the original C-Bridge configuration, there have been a number of changes to the way User Activated (UA) Talkgroups operate.
Select the User Activated talk group as you would any other talk group. Now the chances are you will hear nothing unless the group has already been activated on your local repeater. When a UA is initially accessed by a short PTT press, as soon as the PTT is released, if a transmission is already in progress on that Talkgroup it will be heard. The downside is that during that brief keying period, your transmission will temporarily ‘double’ with the existing transmission and may cause interference. It is therefore suggested that this initial key-up should be kept as brief as possible.
As with the previous configuration, hold-off timers operate to try to prevent these Talkgroups being over-ridden. This timer counts down for 8 seconds at the end of a transmission, which allows enough time for the recommended 3-4 second pause between overs, before releasing the hold-off period. It’s worth noting here that, depending on the server configuration, the hold-off timer period can vary on some UA groups, but is usually a minimum of 8 seconds.
This facility is not implemented on the Phoenix IPSC2 servers. Instead any user activated TG will automatically time out after 15 mins if you don’t transmit to it.. With hotspots using the Phoenix F server, the same applies with Talkgroups, but access to a reflector WILL release when tg4000 is called either as a group or private call.
This server-side timer will ‘hold’ the UA talkgroup on your repeater for 15 minutes and is reset each time you transmit to the group. Each transmission – either yours or someone else’s – will also activate the hold-off timer . This enables users to participate in ‘Round Robin’ type nets without having to key up the repeater just to keep the TG alive. At the end of a 15 minute period with no transmit activity to the repeater by you or any other users on that particular repeater/TG combination, the TG will be released from the repeater.
It is important that users get into the habit of leaving 3-4 second pauses between their overs, otherwise it makes it impossible to change Talkgroups.