P300H P300 Series Modem Installation and Operating Handbook Page 31
Entry Format Fa ult message with time & date. Separate entry when fault clears/
changes
Automatic Entries Average & minimum Eb/No
(user defined Average & minimum estimated user BER
interval) Buffer fill status
Average & 1 minute minimum measured BER from PRBS tester (may
run continuously through ESC or Aux channel for continuous traffic
quality monitoring)
Interrogation method View on front panel LCD, Print to rear panel serial port (`D` type) either
all entries or just unprinted entries read over remote M&C bus
[Auto Uplink Power Control] (AUP C)
Modes of operation: Monitor of distant Eb/No & BER only, Full distant Eb/No maintenance, &
Self monitor (broadcast) modes. Unidirectional or bidirectional operation.
Communication link: Utilises async ESC channel on IBS/ S MS, IDR and Closed Net Plus ESC
carriers (ESC from 300Baud, ie overheads down to <1%).
User parameters: Ta rge t Eb/No, Tolerance window, Max & Min delta powers, Slew rate
limit, comms loss action (freeze, max or nominal power).
Ancillary features: Automatic logging of distant Eb/No and local AUPC delta power at user
controlled intervals in traffic log.
Automatically int erleaves A UPC messages with distant end remote M&C
(if active) on ESC channel.
Independent Max & Min delta powers (ie facility to reduce power & still
maintain quality of service with good atmospherics) allows power
balancing on transponders with traffic to varied destinations.
Common Specifications
Loopbacks Interface Loop (local & remote)
Drop/Insert Loop (local)
Framer Loop (local)
FEC Loop (local)
RS Loop (local)
Internal IF Loop (local, Rx IF automatically tuned to match Tx)
Deframer/Framer Loop (remote)
Test Modes Transmit CW (pure carrier)
Transmit alternate 1,0 pattern (for carrier suppression test)
Disable Reed-Solomon decoder corrections
Alarm Relays 3 independent changeover contacts:
Prompt Unit fault
Prompt Traffic fault (Tx or Rx)
Deferred Alarm (backward alarm, BER or Eb/No below user set
threshold)