Cisco Model 6944 Four Port Optoelectronic Node 870 MHz with 42 54 MHz Split 数据表

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Model 6944 Four Port Optoelectronic Node – 5-55/70-870 MHz 
 
8
 
 
Optical Section Specifications 
 
Optical Section - Forward Receiver Module 
Units 
6944 Standard RX 
Notes 
Wavelength 
nm 
1310 and 1550 
 
Optical Input Range 
mW 
dBm 
0.5 to 1.6 
-3 to + 2 
 
Pass Band 
MHz 
52-870 
 
Frequency Response 
dB 
±
 0.75 
Tilt (
±
 1.5 dB) 
dB 
 
Optical Input Test Point (
±
 20%) 
V DC 
1V/mW 
 
Optical Input Power Threshold for Rx On/Off 
(for Rx Redundancy) 
dBm 
-4 / -6 
RF Output Level @ 
0
 
dBm Optical Input 
dBmV 
Refer to chart (below) 
RF Output Test Point (± 1.0 dB) 
dB 
- 20 
 
 
 
Receiver RF Output Level Vs Transmitter OMI 
(using Standard Receiver) 
19.5
20.0
20.5
21.0
21.5
22.0
22.5
23.0
23.5
24.0
24.5
25.0
25.5
26.0
26.5
2.25%
2.50%
2.75%
3.00%
3.25%
3.50%
3.75%
4.00%
4.25%
Transmitter OMI per Channel
Minimum
RF Output 
Level 
(dBmV)
1310 nm
1550 nm
 
 
 
 
For reverse optical transmitter and link performance, see the “Analog Reverse Optical Transmitters for Model 
6940/6944 and GainMaker
 Optoelectronic Stations” data sheet, and the Model 6940/44 bdr data sheet(s). 
 
 
 
 
Unless otherwise noted, the above specifications reflect typical station performance at stated reference levels in the recommended operating 
configuration(s).  Unless otherwise noted, specifications are based on measurements made in accordance with NCTA Recommended 
Practices for Measurements on Cable Television Systems using standard frequency assignments and are referenced to (20
°
C) 68
°
F. 
Notes for Optical Section Specifications: 
1.  For forward receiver module only.  Does not include frequency response contributions from forward optical transmitter. 
2.  Minimum receiver RF output level for the stated transmitter percent OMI/ch. (Optical Modulation Index per channel), with receiver optical 
input power of 0 dBm.  To determine RF output levels at other optical input power, add (or subtract) 2 dB in RF level for each 1 dB 
increase (or decrease) in receiver optical input power. 
3.  Redundant Control Module (RCM) or status monitoring transponder is required for Rx redundancy.  Threshold stated is for RCM.  
Threshold is adjustable via element management software if Transponder is used (TNCS or equivalent).  Optical input power below the 
“Off” threshold causes an RF switch from Primary Rx to Redundant Rx.  Optical input power above the “On” threshold causes an RF 
switch back to Primary Rx.