User's Manual
Table Of Contents
- Installation and Operation Manual Draft in Progress
- Contents
- Preface
- 1 Description
- 2 General Safety and Regulatory Information
- 3 Operation
- 4 Working with Base Stations from Your PC
- 4.1 PC Recommendations
- 4.2 Connecting Your PC to the Base Station
- 4.3 Working with the Web Interface
- 4.4 Basic Tasks
- 4.4.1 User Settings
- 4.4.2 Taking the Base Station Offline
- 4.4.3 Troubleshooting Alarms
- 4.4.4 Working with Configuration Files
- 4.4.5 Configuring Single Base Stations
- 4.4.6 Configuring Base Stations in a Channel Group
- 4.4.7 Setting Up Custom Alarms
- 4.4.8 Disabling the Front Panel Keypad
- 4.4.9 Preparing to Download Firmware
- 5 Installation
- 6 Maintenance
- 7 Troubleshooting
- 8 Replacing Modules
- Appendix A – Interface Pin Allocations
- Appendix B – Inter-Module Connections
- TaitNet P25 Glossary
- Tait Software License Agreement
DRAFT 4
TB9400 Installation and Operation Manual Installation 85
© Tait Electronics Limited September 2011
5.6.6 Connecting an External Frequency Reference
For K4 Band, the internal frequency reference accuracy is inadequate, and
an external reference (for example, the Tait T801-4) must be used. An
external reference is also required for simulcast. The external reference
frequency can be 10 MHz or 12.8 MHz, with an input level of 300 mV
pp
to
5 V
pp
. The stability of this reference should be better than 50 parts per billion
(for non-simulcast) or ≤ 1 part per billion (for simulcast). The reciter
automatically detects the frequency of the external reference and configures
itself accordingly.
If an external reference is required, enable the external reference “Absent”
alarm (Configure > Alarms > Control).
Use a 50 Ω coaxial cable (RG58 or RG223) to connect the external
reference to the base station’s external reference frequency input. You can
daisy-chain up to eight base stations using T-junctions. The maximum
overall cable length is 30 m. Terminate the last connection with a 50 Ω load.
Figure 5.10 Daisy-chaining an external frequency reference input
50 Ω termination
maximum of eight base
station loads on one
frequency reference output
maximum overall cable
length is 30 m