User's Manual

P.G. TM0032FE
2 - 4
2.2.3 Fault Conditions
- The A211 circuitry monitors four separate parameters in the
unit. These are (a) the bias currents drawn by the transistors in each of the cellular and
PCS amplifiers and (b) the presence of downlink RF output power in each amplifier
band. Each function can be disabled as described in Section 4, if the unit is being used
in a restricted operational mode.
The DC current monitoring triggers a fault condition if the DC bias current deviates
outside predetermined high or low current limits.
The downlink RF output power from each frequency band is monitored by separate
detectors and a FAULT condition is triggered if the level in either band drops below a
nominal level of - 5 dBm. If the amplifier is to be installed at a point in the system where
the output power in either band may be less than -3 dBm then the RF monitor circuit for
the appropriate band should be disabled as described in Section 4 herein.
The local fault indicators indicate specific faults as follows:
CELL
BIAS Bias fault in the Cellular amplifier
PWR Low downlink RF power from the Cellular amplifier.
PCS
BIAS Bias fault in the PCS amplifier
PWR Low downlink RF power from the PCS amplifier