Outdoor CATV Optical Node

Forward optical receiving part

Optical Parameters

Receiving Optical Power

dBm

-9 ~ +2

Optical Return Loss

dB

>45

Optical Receiving Wavelength

nm

1100 ~ 1600

Optical Connector Type

FC/APC, SC/APC or specified by the user

Fiber Type

Single Mode

Link Performance

C/N

dB

≥ 51 (-2dBm input)

C/CTB

dB

≥ 65

Output Level 108dBμV

EQ 6dB

C/CSO

dB

≥ 60

RF Parameters

Frequency Range

MHz

45 ~862

45 ~1000

Flatness in Band

dB

±0.75

±0.75

Rated Output Level

dBμV

≥ 108

≥ 108

Max Output Level

dBμV

≥ 114

≥ 112

Output Return Loss

dB

(45 ~550MHz)≥16/(550~1000MHz)≥14

Output Impedance

Ω

75

75

Electronic Control EQ Range

dB

0～15

0～15

Electronic Control ATT Range

dB

0～20

0～20

Return Optical Emission Part

Optical Parameters

Optical Transmit Wavelength

nm

1310±10, 1550±10 or specified by the user

Output Optical Power

mW

0.5, 1, 2

Optical Connector Type

FC/APC, SC/APC or specified by the user

RF Parameters

Frequency Range

MHz

5 ~ 65 (or specified by the user)

Flatness in Band

dB

±1

Input Level

dBμV

72 ~ 85

Output Impedance

Ω

75

NPR Dynamic Range

dB

≥15 (NPR≥30 dB)

Use DFB laser

≥10 (NPR≥30 dB)

Use FP laser

General Performance

Supply Voltage

V

A: AC (150~265)V; B: AC (35~90)V

Operating Temperature

℃

-40~60

Storage Temperature

℃

-40~65

Relative Humidity

%

Max 95% no condensation

Consumption

VA

≤ 22

Dimension

mm

260（L）* 200（W）* 130（H）

After connecting the

network, the image of the

optical contact point has

obvious netlike curve or

large particles highlights

but the image background

is clean.

1. The input optical power of the

optical receiver is too high, make the

output level of the optical receiver

module too high and RF signal index

deteriorate. 

2. The RF signal (input the optical

transmitter) index is poor.

1. Check the input optical power and make

appropriate adjustments to make it in the

specified range; or adjust the attenuation of

optical receiver to reduce the output level and

improve index. 

2. Check the front end machine room optical

transmitter RF signal index and make

appropriate adjustments.

After connecting the

network, the image of the

optical contact point has

obvious noises.

1. The input optical power of the

optical receiver is not high enough,

results in the decrease of C/N. 

2. The optical fiber active connector

or adapter of the optical receiver has

been polluted.

3. The RF signal level input the

optical transmitter is too low, make

modulation degree of the laser is not

enough. 

4. The C/N index of system link

signal is too low.

1. Check the received optical power of the

optical contact point and make appropriate

adjustments to make it in the specified range.

2. Recover the received optical power of the

optical contact point by cleaning the optical

fiber connector or adapter etc methods.

Specific operation methods see “Clean and

maintenance method of the optical fiber

active connector”. 

3. Check the RF signal level input the optical

transmitter and adjust to the required input

range. (When the input channels number less

than 15, should higher than nominal value.)

4. Use a spectrum analyzer to check the

system link C/N and make appropriate

adjustments. Make sure the system link signal 

C/N﹥51dB.

After connecting the

network, the images of

several optical contact

points randomly appear

obvious noises or bright

traces.

The optical contact point has open

circuit signal interference or strong

interference signal intrusion.

1. Check if there is strong interference signal

source; change the optical contact point

location if possible to avoid the influence of

strong interference signal source. 

2. Check the cable lines of the optical contact

point, if there is shielding net or situation that

the RF connector shielding effect is not good.

3. Tightly closed the equipment enclosure to

ensure the shielding effect; if possible add

shielding cover to the optical contact point 

and reliable grounding.

After connecting the

network, the images of

several optical contact

points appear one or two 

horizontal bright traces.

Power supply AC ripple interference 

because of the bad earth of equipment

or power supply.

Check grounding situation of the equipment,

make sure that every equipment in the line

has been reliably grounding and the

grounding resistance is﹤4Ω.

After connecting the

network, the received

optical power of the optical

contact point is unstable

and has large continuous

change. The output RF

signal is unstable, too. But

the detected output optical

power of the optical

transmitter is normal.

The optical fiber active connector

types do not match, maybe the APC

type connect to PC type, make the

optical signal cannot normal

transmission.

The optical fiber active connector or

adapter may be polluted seriously or 

the adapter has been damaged.

1. Check the type of optical fiber active

connector and adopt the APC type optical

fiber active connector to ensure the normal

transmission of optical signal. 

2. Clean the polluted optical fiber active

connector or adapter. Specific operation

methods see “Clean and maintenance method

of the optical fiber active connector”. 

3. Replace the damaged adapter.