mdc-1200 protocol

The General forum is where users can discuss any topic regarding Motorola communications equipment - hardware, software, etc. There are also several focused forums on this board, so please take the time to ensure that your questions doesn't fall into one of those categories before posting here!

Moderator: Queue Moderator

Post Reply
User avatar
jim
Posts: 2184
Joined: Sun Sep 09, 2001 4:00 pm

Post by jim »

I was on Midian's site (http://www.midelec.com) last night and see that they now offer something called "CAD-500", which is a program that displays real-time user ID status from the received MDC data burst. Did anyone use this program yet?
I like the feature that stores all traffic of the day and logs time/date.
If anyone has this program and can reverse engineer it (which is legal for one's own use), they would be able to find out all we've been wanting to know about MDC-1200 and it's format and how it works.
User avatar
wavetar
Administrator
Posts: 7341
Joined: Sun Sep 09, 2001 4:00 pm

Post by wavetar »

Any company who's willing to spend the money can legally obtain the MDC-1200 protocol theory from Motorola. We did this about 5 years ago & wrote our own simple DOS based software program to display MDC IDs for a local taxi company. It's worked without a hitch ever since. It wasn't cheap (in the thousands of $$), and it only amounted to a few photocopied pages of text, but it allowed us to customize a system for a client who was willing to pay for it.

Todd
Will
Posts: 6823
Joined: Tue Sep 04, 2001 4:00 pm

Post by Will »

A related MDC issue. How do you get a HT1000 to mute out the MDC signalling on receive. There is an agencey here who uses the MDC on the END of all their transmissions and it drives the monitors nuts listening to the data bursts. Should,t the repeater strip off the data burst? The DOS (data operated squelch) seems to cut off the first part of all the transmissions. Is there somthing I am missing to get the HT1000 to mute the data burst?
User avatar
alex
Administrator
Posts: 5762
Joined: Mon Sep 03, 2001 4:00 pm

Post by alex »

You have to set up the channel to do MDC itself. However, you will still get little "chirps" the radios have no way of telling another radio hey, i'm about to de-key. mute...

If you are talking about the full databurst, I'd have to go back and look at the software again but I believe you have to make sure it's set to transmit / rcvc MDC. IF you have QCII on the channel, it will not trap the MDC bursts, and the end user would hear them as normal traffic.

-Alex
User avatar
alex
Administrator
Posts: 5762
Joined: Mon Sep 03, 2001 4:00 pm

Post by alex »

I personally would love a little utility I could hook up to a scanner that would decode MDC, just so I could get the radio ID's on a system. It would be pretty cool. If someone made a small decoder box it would be a very nice thing to have. I thought at one point optoelectronics made a box that would do it, but I could be wrong.

-Alex
User avatar
perthcom
Posts: 280
Joined: Sat Dec 08, 2001 4:00 pm

Post by perthcom »

The DOS (data operated squelch) keeps the speaker muted for a short period of time at the beginning of the beginning of reception to keep PRE PTT ID's squaks from being heard.
You have to set the channel up to decode MDC in order for it to mute any MDC at the end of the transmission. Which means like Alex said, you can't do QCII and MDC, as far as i remember.

Bruce
Post Reply

Return to “General Motorola Solutions & Legacy Radio Discussion”