ComSonics CyberTek QUALIFIER, User Manual

Qualifier System

2-1

Home Qualifier System - Overview

ComSonics Cybertek Home Qualifier System provides a method for identifying the internal
shielding integrity of the CATV network in a subscriber’s home without the need to enter
the premises. A Test Source Transmitter (TST), installed in a service vehicle, generates a RF
envelope that blankets the home. A Test Key Transmitter (TKT) is located within the
Qualifier meter, a hand held unit. The TKT provides an activation signal to the TST in the
service vehicle and sets up the Qualifier meter to measure levels of ingress from the TST
signal appearing in the upstream path. With the Qualifier meter connected to either the home
ground block or the drop at the tap, a press of the Qualifier meter’s “Q” key instructs the
TKT to activate the TST. The TST generates a brief 5-watt pulse at a frequency just above
the CB radio band. The frequency is factory set and is within the upstream spectrum. The
TST signal envelopes the home with a level of about +58 dBmV (assumes the service
vehicle is about 75 feet from the home). Shielding flaws within the in-home cabling allow
the TST signal to enter the upstream path and to the Qualifier meter test connection. The
Qualifier meter performs measurements at precisely the right time to detect, measure, and
display the level of the TST signal at the selected connection point.

Basic steps for qualifying a home:

1.

Park the Qualifier equipped service vehicle near the home you are qualifying. Preferably
about 75 feet from the home and no greater than 150 feet.

2.

Set the transmitter power switch to ON.

3.

Disconnect the CATV drop cable from the home ground block / splitter. An alternative
method is to disconnect the drop at the tap / pedestal.

4.

Use a short jumper cable to connect the Qualifier meter to the appropriate ground block
terminal for testing. If using the tap / pedestal method, connect the meter to the free end
of the drop cable. If needed, use a quality extension cable and a F-81 barrel. Make sure
the connectors are tight. You will be measuring a Qualifier system generated test signal
ingressing into the home cabling that would normally travel to the headend in the
upstream path.

5.

Power the Qualifier meter ON.

6.

Press the “Q” key to enable the meter’s Qualifier Mode.

7.

Press the “Q” key a second time to activate the transmitter and to initiate the
measurement sequence.

8.

The yellow TX light on the transmitter illuminates and the home is enveloped by a 5-
watt test signal burst.

9.

The meter detects and measures the level of test signal ingress into the home.

10.

The meter displays a level measurement indication of test signal ingress.

Hint:

•

  For a high level reading from a tap / pedestal location, retest from the home ground

block / splitter location.

•

  For a high level reading when connected to the input of a home splitter, disconnect

each cable from the splitter output (one at a time) and retest to determine the path of
ingress.