4. HARDWARE
CONNECTIONS
a. The CTA-30RK-1000 is designed for installation in a standard 19” EIA rack.
b. Connect a 75ohm coaxial cable with F-connectors from the headend combiner output
to CTA-30RK-1000’s In Port. Do not exceed the unit’s maximum input level.
c. Connect a 75ohm coaxial cable with F-connectors from the CTA-30RK-1000’s Out
Port to the main RF distribution network. Do not exceed the unit’s maximum output
level.
d. Terminate the Test port with a Cabletronix F-TM3GZ terminator when not in use.
e. Connect the CTA-30RK-1000 to an appropriate power source capable of powering this
device. Be certain that power source is capable of handling the load if the
CTA-30RK-1000 and other equipment are being powered by it.
5. ADJUSTMENT
The chart below shows the proper operation levels for the CTA-30RK-1000. Note the listed
performance criteria are for specific numbers of channels, and must be de-rated accordingly
when inserting additional channels. However, the amplifier’s available power does not change.
Therefore, as the number of channels increases from seven (7) channels, the input level and
the output level must be reduced. Exceeding the input levels listed below will product
intermodulation and picture distortion.
Number
Of Channels
Maximum
Level Input (dBmV)
Maximum
Level Output (dBmV)
7 44 66
12 41 53
36 32 54
54 23 45
78 18 40
108 14 36
125 11 32
158 8 30
Turn the CTA-30RK-1000’s RF Gain control to achieve the maximum output levels identified
above. Attenuators may be needed to achieve the above maximum input levels.
The CTA-30RK-1000’s Tilt control should be used to set the appropriate slope per system
specifications. Note that the Tilt allows the adjustment of the gain-to-frequency characteristic
of the amplifier.
When making adjustments always apply the following principles:
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Input signal levels should ALWAYS exceed the noise figure of the amplifier by 3 to 6
dB.
3
The primary purpose of tilt (equalization) in a cable TV plant is to compensate for the
slope generated in coaxial cable between the high and low TV frequencies. When
various TV channels, with respect to frequency, are transmitted through coaxial cable
they are subjected to increasing attenuation (loss). Simply put, as the frequencies of
the TV carriers are increased, attenuation loss (dB) increases. A variable tilt control is
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