Cisco Cisco Digital Service Access Node (DSAN) 8211 Troubleshooting Guide
Chapter 2 Hardware Installation
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4032301 Rev A
RF Level Setup
This section describes procedures for ensuring appropriate RF signal levels at each
of the DSAN signal ports.
of the DSAN signal ports.
Note: You can perform these procedures immediately after applying power to the
DSAN.
DSAN.
Forward Path Downstream Signal (Port 1)
1 Connect the cable plan to the Input port (Port 1) on the DSAN unit.
2 Connect the test equipment to the Input port test point (FWD IN -20dB TP) on
2 Connect the test equipment to the Input port test point (FWD IN -20dB TP) on
the DSAN unit.
3 Measure the signal levels at the lowest frequency and highest frequencies
specified in the system design.
4 Adjust the FWD IN EQ to flatten the frequency spectrum. Adjust the FWD IN
PAD to adjust the level of the input signals.
Note: A FWD IN PAD value of 1 dB and a FWD IN EQ value of 0 dB give the
proper setup for a flat input spectrum with digital signal levels at +4 dBmV
(analog channels are + 10 dBmV, or 6 dB higher than digital). Changes in the
FWD IN PAD and FWD IN EQ values will not change the measured results at
the FWD IN -20 dB test point because this test point is located ahead of the input
accessories.
Note: A FWD IN PAD value of 1 dB and a FWD IN EQ value of 0 dB give the
proper setup for a flat input spectrum with digital signal levels at +4 dBmV
(analog channels are + 10 dBmV, or 6 dB higher than digital). Changes in the
FWD IN PAD and FWD IN EQ values will not change the measured results at
the FWD IN -20 dB test point because this test point is located ahead of the input
accessories.
5 Connect the test probe to the Mixed Services output port (Port 3) test point (FWD
OUT -20 dB TP3).