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triggered MDC group call

Posted: Tue Jan 15, 2008 3:13 am
by libuff
Hey all,
i hate to re-open old topics/wounds, last discussion ended up suggesting that i went to the county dispatcher and telling them how to do their job, can't do...

trying to setup a module to xmit a group call upon receipt of a trigger. we currently have a modidified Minitor 2 amp pager base, which rebroadcasts a VHF QC2 Page onto UHF. Additionally we are looking to also send a MDC1200 Group call to a certain code upon receipt of a call.

our UHF radios are used for operations on the EMS side, and have seperate F/G channels so were not disturbed on a long term scene. So... i want to setup a channel as MDC signaling "AND" setup for a "Group Call" from mdc to unmute the channel.

is there such a thing? or am i barking up a tree?

Re: triggered MDC group call

Posted: Tue Jan 15, 2008 12:57 pm
by HumHead
I've done the exact same thing. After a lot of searching, I have not yet been able to find a simple (or cheap) way to do it.

For the installation that needed the feature, I ultimately ended up taking a Midian UED-1B and using it to generate DTMF in response to a QCII page. The DTMF is then fed into a Motorola i750r controller which outputs the correct MDC group page.

Unfortunately, I do not know if the i750r is even available anymore. If I have to do it again, I would probably interface something like an MC2000 deskset to the repeater and modify it to bring the contacts for one of the buttons, programmed for the MDC call, out to an external contact closure.

Re: triggered MDC group call

Posted: Tue Jan 15, 2008 5:55 pm
by RKG
Not sure if this helps:

Zetron consoles have what is known as "spare inputs" (not to be confused with "auxiliary inputs"). When a "spare input" is made active, it will command any command that can be programmed with a key (i.e., the activation of the input is treated as a button push), such as the "instant page" feature.

Now, you don't have access to a console. However, I think I recall that you can do the same thing with a Zetron M280 or M284 tone remote.

Re: triggered MDC group call

Posted: Sun Jan 27, 2008 8:19 am
by libuff
playing around a bit with my xts2500... it seems that it ALLOWED me to enter Exxx as a MDC ID...

currently mysetup is made up of a Minitor 2 pager, connected with some magic to the mic connector of a CDM1550... can i set the radio ID to Exxx, to make a group call?

Re: triggered MDC group call

Posted: Sun Jan 27, 2008 8:32 am
by RKG
Any command sent by an MDC sender addressed to an address of Ennn is, by definition, a group call. It will not be recognized by any primary MDC ID, but rather by those subscribers whose radios permit "variable" IDs and whose "variable" ID is programmed as nnn.

Re: triggered MDC group call

Posted: Sun Jan 27, 2008 5:03 pm
by libuff
RKG wrote:Any command sent by an MDC sender addressed to an address of Ennn is, by definition, a group call. It will not be recognized by any primary MDC ID, but rather by those subscribers whose radios permit "variable" IDs and whose "variable" ID is programmed as nnn.
right... so if i were any mobile/portable with mdc decoder decodes an ID of Ennn, and nnn was their valid fleet/group code, it should alert? i don't have too many radios to play with, but im going to try and get back to you fellas!