A Push to talk enebled phone will consist of a external soft key which when pressed will activate a direct [one way] line to all those you have configured your PTT key to work with. eg. your work group.
Exactly like a walkie talkie.
Or rather a PA system if only you phone has PTT.
Of course you will have to activate the service with your network provider
Its gr8 if:
a> you have a large work group to whom you need instant connectivity
b> you are a security guard
c> you wanna play agent 000
for b and c, its much cheaper to buy and operate a real walkie talkie.
Advantage of PTT over walkie talkie:
a> long, very long [network wide] range
b> kids with an extended range fm reciever cant eavesdrop. [FYI: AAI {airport authorities india} [mumbai] is roughly 150MHZ
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