Digital Equipment ChannelWorks DECTV-AA, Installer'S Manual

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1-10 ChannelWorks Cable TV Installer’s Guide
Spurious Output -45 dBc
Return Loss (TX Port) 14 dB
Receiver
Minimum Frequency Range 54 to 550 MHz
Receive Level
−
5 to
+
15 dBmV
BER @ 25 dB C/N
<
1 in 10
9
Return Loss (RX Port) 10 dB
TransMaster
Set-up and installation procedures for the translator are located in Chapter 3, “Setting
Up the Headend Translator.” The following list contains the RF electrical specifica-
tions for the TransMaster single channel translator.
Input Frequency Range 8.75 to 550 MHz
Output Frequency Range 51 to 550 MHz
Frequency Step 250 KHz
Frequency Stability/Accuracy
±
750 Hz 0
°
C to 40
°
C
Gain 30 to 50 dB (adjustable)
Bandwidth
−
3 dB @
>
5.2 MHz
−
40 dB @
>
7 MHz
Spurious Products
>
60 dB below max output level
Cable TV Network Requirements
The following list contains the required specifications that a cable TV network must
meet in order for the ChannelWorks Bridge to operate properly when connected.
Nominal Impedance 75 ohms
Return Path Outlet-to-Outlet Variation
≤
6 dB
Amplitude Flatness
±
1 dB
Group Delay
±
10 nsec
Carrier to Hum Ratio
≥
34 dB
Carrier to Noise Ratio
≥
40 dB
Carrier to Second Order Beat
≥
60 dB
Carrier to Third Order Beat
≥
78 dB
Carrier to Adjacent Channel Interference
≥
36 dB