Scanners and MDC - That AWFUL Squawk...

[Gezelle007]

I'm waking up an old thread here, but has anyone found a Kenwood Fleetsync decoder, like WinMDC?

 

[RKG]

MDC can transmit the characters 0 thru 9 and the letters A, B, C, D or E. It actually uses hex numbers from 0001 thru DEEE, which allows up to 57070 different ID's. I don't know why the letter "F" is not allowed.

Using Motorola MDC 1200, the rules are as follows:

An MDC1200 ID is a four-digit hexadecimal number.

"0000h" is not permitted.

"F" is not permitted in any digit. (F is a wildcard value, used when an MDC command is sent to subscribers.)

"E" is not permitted in the first digit. (An E as the first digit signifies a group target, versus an individual target.)

As a result, there are 47,249 possible valid MDC IDs. ((14*15*15*15)-1.)

 

[RKG]

"I don't know why the letter "F" is not allowed."


Because "F" is involved in MDC "All Calls", IE if you were to page "FFFF", all radios with MDC enabled, presuming that MDC RX Alerts ara enabled in CPS/RSS, they would all go off on that frequency. One of my AstroSaber's can do it, but that's the only radio I have that can from the front panel.

Close: in the MDC1200 realm, F in any digit is considered to be a wildcard. So, for instance, a command sent to "###Fh" would be addressed to 15 addresses: ###0h through ###Eh. Wildcard are generally used where MDC1200 ID schemes used tiered digits. For example:

First Digit: 1 is portable, 2 is mobile, 3 is control station.
Second Digit: 1 is command staff, 2 is suppression company, 3 is other
Third Digit: serial within second digit.

Group calls (of which "all call" is the ultimate example) are usually handled differently. For sub-groups, you can assign all members of a given sub-group with the same three-digit "secondary" ID, and a command sent to that ID with an E prefixed to it will be interpreted as a group call. You could make an "all call" this way, but a simpler way involves using a "group tone" on the primary ID, such as A-B, Long B. Here, instead of sending the A-B tone sequence, you send 6 seconds of the B tone, and all units with the same B tone will respond.

 

[RKG]

Thanks for the information on WinMdcd. I just installed it, nothing more than an .exe file. It works without doing anything else.

I'm just not sure what the numbers mean! What is arg? I assume the id is the system's method of identifying the radio.

I've attached a screen shot.

MDC1200 includes a number of commands and responses. While "PTT ID" is the most common, it is not the only one. A partial list of others include page ("alert"), selective call ("selcall"), radio check, radio kill, radio revive, message, and status, as well as various acknowledgement words. What you see as "OP" and "ARG" differentiate among these various commands and responses.

From memory, OP=01 is PTT-ID.