LAND MOBILE PRODUCT SECTOR
1301 E. ALGONQUIN RD.
SCHAUMBURG, IL. 60196
(847) 576-0180

SUBJECT: LOSS OF RANGE AFTER SYSTEM MIGRATION TO MTR2000

MODELS AFFECTED: TRUNKED MTR2000 T5544A ALL FREQUENCY BANDS

SYSTEMS AFFECTED: TRUNKING RADIO SYSTEM CENTRAL CONTROLLER OR STARTSITE CONTROLLER

SYMPTOM: After migrating to MTR2000 stations from MSF5000 or Quantar/Quantro systems, some users have experienced a loss of operational area coverage in their systems. It has been discovered that MTR2000 host software releases have different throughput delay on the control channel compared to QUANTAR/QUANTRO or MSF5000 stations. This difference in delay could result in a reduction and/or change in the ISW decodes range of the system.

Transition from MSF5000 to MTR2000

Host software version R003.01.06 and subsequent versions will implement internal timing changes to ensure that ISW timing is fully compatible with MSF5000 stations. No change in IRB T0 setting is or will be necessary for these newer host SW versions.

However, for older versions of MTR2000 host SW (versions up to R003.01.04) the recommended IRB T0 settings for different frequency bands and channel spacing are shown in Table 1. It will compensate for any changes in delays in the MTR2000 stations compared to MSF5000 stations, which is used as benchmark. These settings will allow the subscriber radios to communicate over the maximum usable distance. If less coverage is desired, then decrease the T0 counter in steps of 1 until the desired coverage from the site is reached.

If the system still has the default IRB T0 setting of F6, use the Hexadecimal setting number in the appropriate field in table 1. If the setting has been altered because of other system requirements, increase the setting of the T0 counter by the amount shown in brackets. If the desired range is not achieved, increase or decrease the T0 counter in steps of 1 until the required range is reached.

RECOMMENDED T0 SETTINGS FOR

Table 2: Transition from QUANTAR/QUANTRO to MTR2000

It is necessary to determine if IRB T0 settings have already been changed from the default value of F6 to accommodate system requirements with QUANTAR stations. If so, follow instructions given in Table 2. If the T0 timer is still at default setting of F6 set the T0 timer per table 1.

Change IRB T0 timer setting by

NOTES :

Version A and B IRB boards have one 8-bit T0 timer for all four channels. Therefore, this recommendation may not work in existing systems with version A or B IRB boards and a T0 setting of FD or greater.

Systems with version A and B IRB boards have only one T0 timer, therefore all four control channels must be the same model basestation (1.e. all MICOR, all MSF, all Quantar/Quantro). In this configuration MTR2000 stations that are control channel capable must contain the same firmware versions within a site.