The DisplayMax 800 is powerful enough to maintain the headend, yet simple enough for routine installation checks. With a wide range of measurement options, a technician can quickly check an individual channel, favorite channels, all channels, tilt, ingress, C/N or HUM.

The graphic display allows a technician to view the full system response and quickly identify problems such as low level, roll-off, suck-outs or missing channels. In the ingress mode, the graphic display shows a spectrum analyzer view of the full return path, revealing any unwanted ingress signals.

All multi-channel modes are supported by an automatic pass/fail test that compares all measured channels against user defi ned parameters. In less than one minute a headend technician or installer can scan up to 135 channels and verify that all analog and digital channels are within tolerance.

Data recording permits all measurements to be saved and downloaded to a computer.

VoIP and High-Speed Data Qualifier
Qualifying the drop and home wiring for VoIP and HSD services requires more than just checking signal level. Although proper signal level is important, verifying the shielding properties of the coax is equally important. Why is shielding important? Bad shielding allows unwanted signals (ingress) to enter the return path and slow down or abruptly stop digital services. Since more than 90% of ingress is generated at the drop and home wiring, it is necessary to check all installations for good shielding.

To test the entire home for ingress, disconnect the ground block and connect the meter to the home wiring. Performing an ingress scan will immediately show if ingress is present. A peak-hold mode will capture intermittent ingress if left running for a longer period of time.

Since shielding problems also allow forward channels to escape from the cable, a leakage detector is very effective in fi nding the source of an ingress problem. The Displaymax 800 can perform leakage testing when upgraded to model 800CLI.