Digital Equipment ChannelWorks, Network Installer Manual

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B-8 ChannelWorks Network Installer’s Guide
CABLE PLANT SITE EVALUATION
(to be completed for each install location)
1
➙
What is the one-way cable distance (in feet) of this location from the headend? ______________
2
➙
What is the number of amplifiers between this location and the headend? ______________
Grp 1
➙
What does the system require for a transmit signal level at the outlet
to insure proper input level at first amplifier?
From Outlet Location
➙
Inject a CW signal on the assigned return center frequency at the outlet.
Measure at the headend. Record:
Injected Signal Level at outlet
Measured Signal Level at headend
Equivalent Translator Input Level
(if not the same as test point)
➙
Vary injected CW signal
±
3 MHz* from center in 500 KHz increments.
Measure at the headend. Record:
Injected Signal Level at outlet
Minimum Signal Level at headend
Maximum Signal Level at headend
From Headend
➙
Inject a signal on the assigned forward center frequency at the headend.
Measure at the outlet. Record:
Injected Signal Level at headend
Equivalent Translator Output Level
(if not the same as test point)
Measured Signal Level at outlet
➙
Vary injected signal
±
3 MHz* from center in 500 KHz increments.
Measure at the outlet. Record:
Injected Signal Level at headend
Minimum Signal Level at outlet
Maximum Signal Level at outlet
Grp 2
➙
Carrier to Noise Ratio
➙
Carrier to Hum Ratio
➙
Carrier to 2nd Order Beat
➙
Carrier to 3rd Order Beat
*NOTE: You use an LCT, which employs a 5.2 MHz filter, on single cable, cable TV plants. Therefore, inject the
CW signal
±
2.50 MHz from center.
Site Name:
Site Location:
Contact Name:
Phone:
Fax:
dBmV
dBmV
dBmV
dBmV
dBmV
dBmV@ MHz
dBmV@ MHz
dBmV
dBmV
dBmV
dBmV
dBmV@ MHz
dBmV@ MHz
dB
dB
dB
dB