MCD 5000 Deskset not able to Radio Inhibit APX2000 via MOTOTRBO DM4601e radio


Symptom(s)

APX2000 radio does not respond to the Radio Disable/Enable command sent by MCD5000 Deskset.

Issue

MCD 5000 Desksets communicating via a managed switch to an RGU that is connected to a DM4601e mobile radio. User send an MDC "Radio Inhibit" page from the MCD5000 Deskset to a specific GP328 or APX2000, based on its MDC radio ID. This system works 100% reliably when communicating with a GP328, but it is being very unreliable with the APX2000s. Sometimes user need to send repeated inhibit commands for about 20 mins before the APX2000 will actually get inhibited (but then it works reliably from there until they shut any part of the Deskset system down again). Customer tried adjusting all of the different parameters in the various configurations, but nothing has resolved the issue. There might be a software fault somewhere between the MCD5000s and the DM4601e radios, and the GP328s just handle this fault better than the APX2000s.

Environment

MCD5000 GU Release Data : v2.5.0

RGU GU Release Data : v2.5.0

DM4601e Firmware Version : R02.21.01.0000

APX2000 radio firmware version :- R24.01.00
 
MCD5000 CT tool version :- R 2.5.0
 
RGU to MOTOTRBO radio connected via FKN0012 cable.
 
Connection between RGU port to MOTOTRBO radio is MOTOTRBO over IP radio type.

Resolution

Performed 2 changes as below.

 
Change #1
 In the RGU configuration, under Radio Resource Properties, Advanced:  increment the gain of the MDC modulator.   Discriminator value set at 17. Recommended the Modulator Gain value from 25 and up to the max of 31 the deviation.
 This change immediately made the APX2000 radio start seeing the MDC1200 Signal in the receiver.   A setting of 25 or more for the Modulation Gain in the RGU is necessary to guarantee proper operation of the APX2000 radio.
 
However, still the System ( Mototurbo DM4601/ Deskset- RGU) wasn't understanding the Ack from the portable. Hence it was going into retries and finally declared as "Failed". To fix this perform change #2
 
image.png
 
Change #2:
In the Codeplug of the DM4601, General -> Accessories: change the setting of the Rx Audio Type to Flat Unsquelch
 
Make sure only Deskset is sending out MDC1200 signals.
1) In the CT access the "Radio Resource Properties" tab, select the appropriate radio port, and then click the "Advanced" button. 
2) This will bring up the "Advanced Configuration" dialog for that radio port.
3) Select the "MDC 1200 and Paging" tab.
4) The "Enable MDC 1200" checkbox should be checked.