WARNING :
TO PREVENT SHOCK HAZARD, DO NOT EXPOSE THIS UNIT TO RAIN OR MOISTURE.
THIS APPARATUS SHALL NOT BE EXPOSED TO DRIPPING OR SPLASHING AND THAT NO OBJECTS FILLED WITH LIQUIDS,
SUCH AS VASES, SHALL BE PLACED ON THE APPARATUS.
WARNING :
THIS PRODUCT IS A CLASS-I CONSTRUCTION. PLEASE ENSURE A CONNECTION TO MAINS SOCKET WITH A
PROTECTIVE EARTHING CONNECTION.
PRECAUTIONS
REQUIREMENT
Facilitate service and maintenance
Allow a minimum of 35 in.(90 cm) clearance in front of the equipment rack(s)
Avoid direct heating or air conditioning
If unavoidable, use deflector plates
AC Power source outlets
Locate equipment near sufficient outlets to provide power for test equipment and power tools.
Rack support
Make certain rack supports are sufficiently rigid to support rack(s)
Building leakage
Beware of dripping water onto equipment from leaky roofs, waveguide roof entries, and cold water pipe condensations.
INSTALLATION PRECAUTIONS TABLE
NO SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED SERVICE PERSONNEL .
REMEMBER TO REPLACE COVER AFTER ADJUSTING
COVER MUST BE IN PLACE FOR CE, SAFETY AND PROTECTION
CAUTION
The exclamation point within an
equilateral triangle is intended to
alert you to the presence of
important operating and
maintenance (servicing)
instructions in the literature
accompanying the product.
The Lightning flash with arrowhead symbol
within an equilateral triangle is intended to
alert you to the presence of uninsulated "
dangerous voltage " within the products
supplementary external power supply
enclosure that may be of sufficient
magnitude to constitute a risk of electrical
shock to persons.
Risk of Electric Shock
Do not Open
NOTE TO CATV SYSTEM INSTALLER
This reminder is provided to call the CATV System Installer’s attention to Article 820-40 of the NEC that provides guidelines for proper
grounding and, in particular, specifies that the cable ground shall be connected to the grounding system of the building, as close to the
point of cable entry as practical.
INSTALLATION AND SETUP GUIDELINES
1.
Gain & Cable Slope Controls are reachable under the Cover. Refer to layout scheme for controls adjustment.
2.
This product is shipped with default 0dB pad for all plug-in attenuator and equalizers.
3.
Before applying power to the amplifier make sure that the forward input level to the amplifier is not too high or damage to
the amplifier might occur. To be on the safe side, you should select the input fixed attenuator to max. value (20dB) before
powering the LHA.
4.
Please check that the forward input and mid-stage fixed equalizers are set to 0 dB as factory default values.
5.
Now apply power to the amplifier and measure the amplifier forward output level at the 20dB output test point. If it is very
low then adjust the value of input fixed attenuator until the desired output level is reached at the highest operating
frequency. Remember that the level measured at the test point is 20dB lower than the real signal level.
6.
Set the forward input equalizer value to adjust the output level to be flat across the full bandwidth. The input signal level
will now be flat too. Under this condition there will be best CNR across the full bandwidth.
7.
Now install a plug-in equalizer into the forward mid-stage equalizer socket to get as close as possible to the desired output
signal slope. The desired output slope is determined by your system design. Consult your system planner or your system
maps for this information. Equalizers are available in 2dB steps from 3 to 13dB at 1000MHz. .
8.
If you are having trouble obtaining the expected output levels then check the input test point to verify that the levels are as
expected at the input of the amplifier. The forward set up is complete.
9.
For the reverse path, inject into the forward output test point test carriers with the system design input signal level +20dB
(because the test point has 20dB loss)
at each end of the upstream band.
10.
Verify that the upstream reference test point
(Note: this is commonly called the “X point” and it is measured at your node, or optical
receiver, or at the 1
st
downstream amplifier. Consult with your system designer)
has the proper upstream output signal levels. If it
does not then select the appropriate fixed attenuator and equalizer and install them in the reverse amplifier output sockets.
11.
Record the in/out operating levels and the pad and equalizers used in this station.
Block Diagram
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LHA41RM_V1 July09
