This is merely a historical archive of years 2008-2021, before the migration to mailman3.
A maintained and still updated list archive can be found at https://lists.osmocom.org/hyperkitty/list/op25-dev@lists.osmocom.org/.
Andrew Porrett wap@ica.net [op25-dev] op25-dev at yahoogroups.comAt 08:44 PM 08-05-2017, gnorbury at bondcar.com [op25-dev] wrote: > >Operationally, when a user keys the PTT button on a P25 radio, a >series of messages are exchanged that either grants or denys access >to the requested TGID. Typically the user hears a "beep" or a >"bong" and at that point they can start speaking and this is >transmitted over the uplink freq. The repeater then turns the data >stream back around and retransmitts it on the downlink for other >affiliated radios to receive. This is not correct. You suggest that there is "a series of messages" followed by "turns the data stream around and retransmits it"; that's an odd way to describe a single inbound request and an outbound grant. > As a "fly on the wall" scanner user, OP25 can monitor for these > messages and use them to determine where to tune, what tgid and > timeslot etc. When the PTT key is released, more messages are > passed and a message pops out on the control channel notifying > client radios that the call has ended. How would radios sitting on a voice channel see this message on the control channel? And why have we never seen evidence of such a "call is over" message on any P25 control channel? -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.osmocom.org/pipermail/op25-dev/attachments/20170508/94f11639/attachment.htm>