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4.0
ANNOUNCEMENTS
A.
Received power: the received power should be between -12~+2dBm (1- to 0
is optimal), received power too low also may continue to operate, but CNR will
rapidly deteriorate. Received power too high will cause CTB, CSO deterioration.
When received power>3dBm(2mW) may damage optical receive module.
B.
RF output level: optical receiver’s RF output level related to receive power
and optical receiver’s RF drive level (that is modulation coefficient). Received
power to increase or reduce 1 dB, optical receiver of the RF output level would
increase or decrease 2 dB (1:2). Optical receiver RF drive level to increase or
reduce 1 dB, optical receiver RF output level would increase or decrease 1 dB (1:1).
When received power is –2dBm, RF output level is 35dBmV±1dB. RF working
output level can modulate through ATT1. *(Note, for high output models, there is
an additional RF level control <red know> on top of receiver <top of chassis> that
should be used to adjust the RF output level).
C.
CTB and CSO: RF output level too high will cause CSO and CTB index to
experience deterioration. Output level increase 1dB, CTB deteriorates 2dB, CSO
deteriorates 1.5dB.
D.
When properly adjusted, the optical receiver RF output level should ensure
the distortion index CTB≤-65dB, CSO≤-60dB.
