Product specifications

UT-4500-A Series Upconverters Revision 1

Appendix B MN-UT4500A

B–2

B.2 Backup Upconverter

The "Daisy Chain" terminates in the backup upconverter. The backup upconverter has a

microprocessor, which performs fault detection, self-reconfiguration and the logical switching

functions. If the backup upconverter does not have a fault, it will assume the frequency and

attenuation of the faulted upconverter and compensate for the chain losses. This capability is

accomplished through the operation of the HSB and the online upconverter detachable switch

modules.

B.2.1 High Speed Bus (HSB)

In the "Daisy Chain" configuration, the backup upconverter communicates with the online units

through the HSB. The backup upconverter is able to detect faults and reconfigure itself to

replace the faulted upconverter. The HSB interface is also used in the backup converter to

monitor configuration changes made to an online upconverter. Changes in frequency, gain, or

polarity are immediately entered into the backup table as well as information from new online

units. The high-speed bus does not interfere with the remote serial communication link access

to any of the upconverters in the chain.

B.2.2 Detachable Modules

Comtech EF Data's upconverters are designed with a detachable Input/Output Module (IOM)

which contains the signal path connectors. The IOM is utilized for single thread operation, or for

testing of the unit.

For redundant "Daisy Chain" operations, the online upconverters are provided with a

detachable Transmit Switch Module (TSM) replacing the IOM.

Refer to Chapter 3. REAR PANEL CONNECTORS, Sect. 3.2.2.2 for quick reference tables for the

modules available to both the UT-4500-A Series Upconverters and the DT-4500-A Series

Downconverters.

B.2.2.1 Upconverter Switching

Upconverter switching is implemented with a detachable TSM. The TSM contains IF and RF

transfer switches for input/output looping of the signal. Options for the TSM include Type ‘SMA’

connectors for the RF output signal, and 50 or 75Ω BNC connectors for the IF.