We will take it you have channels set in your radio with Talk Groups you wish to use.
Go to a Channel/Talk Group you wish to Talk on.
PTT for up to 3 seconds and this will link you to that Talk Group.
When you next PTT you will be going out on that Talk Group.
Now you can TX and RX in that Talk Group.
1st PTT only tells the system that you wish to use that Talk Group
To go to a new Talk Group.
4000 Unlink is not required.
Go to a Channel/Talk Group you wish to Talk on.
PTT for up to 3 seconds and this will link you to that Talk Group.
When you next PTT you will be going out on that Talk Group.
Now you can TX and RX in that Talk Group.
You can also access all Talk Groups this way when not as a channel in your radio.
Linking to Talk Groups via TG9
This is a very handy way to go to any/all Talk Groups