Rx Alm 1 Indicator (Only For 1+1 System); Rx Alm 2 Indicator (Only For 1+1 System); Tx Opr 1 Indicator (Only For 1+1 System) - NEC PASOLINK Training Course

ROI-S04488

RX ALM 1 indicator (Only for 1+1 system)

Lights when:
• Receiver input level decreases lower than a preset value from
squelch level at the No. 1 channel ODU,
• APC loop of the local oscillator unlocks at the No. 1 channel ODU,
• IF signal is lost at the No. 1 channel DEM,
• High BER is worse than preset value (1 × 10
• BER is worse than preset value at the No. 1 channel DPU (1 ×
−3 −4
, 1 × 10 , 1 × 10
10
• Frame synchronization is lost at the No. 1 channel DPU,
• Communication between CPU of No. 1 channel ODU and CPU of
the IDU is lost.

RX ALM 2 indicator (Only for 1+1 system)

Lights when:
• Receiver input level decreases lower than a preset value from
squelch level at the No. 2 channel ODU,
• APC loop of the local oscillator unlocks at the No. 2 channel ODU,
• IF signal is lost at the No. 2 channel DEM,
• High BER is worse than preset value (1 × 10
channel DPU,
• BER is worse than preset value at the No. 2 channel DPU (1 ×
−3 , 1 × 10 −4 , 1 × 10
10
• Frame synchronization is lost at the No. 2 channel DPU,
• Communication between CPU of No. 2 channel ODU and CPU of
the IDU is lost.

TX OPR 1 indicator (Only for 1+1 system):

Lights when the modulator and transmitter of No. 1 channel are
selected.
−3
−5 −6
or 1 × 10
selectable),
−5 or 1 × 10 −6
selectable),
OPERATION
) at the DPU,
−3
) at the No. 2
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