Disable Channel Chat only in a specify Channel

I want to disable the channel chat in only one channel on the server for the default users. How can i do this or is it possible?

Set b_client_channel_textmessage_send with Value [ ] into the channel.
Now set b_client_channel_textmessage_send with values [X] [ ] [X] into the server groups that should be able to write message.

To explain my [ ]
First one is Value
Second one is Negate
Third one is Skip

I always thought its impossible, nice one

How do i make so no one can talk in the "lobby / Afk" channel that i have in my teamspeak?

Question for server permission.

How can I disable channel chat in a specific channel? for example AFK room and entry room.

You could set the permission b_client_channel_textmessage_send and remove the value checkbox. This way, regular client would not be able to chat in these channels (while admins ignoring channel specific permissions still can).