11
Model Three - Operation Manual
Spectrum Display
Press the
SPECT
SPECT
6 PQR
(SPECTRUM)
key to display the spectrum
measurements with frequency spans from 2.5 MHz to 62.5 MHz or a
full-spectrum scan.
Hum Display
Press
HUM
to measure the Hum interference of the CATV
transmission system.
QAM Measurement
The Model Three is capable of measuring the channel power of QAM,
QPSK, and COFDM signals. This function also enables the
measurement of pre- and post-BER and MER for QAM modulated
signals. The QAM measurement mode also features a single channel
spectrum display and an optional Constellation diagram is available to
enable users to find errors more quickly.
Data Logging
You can select and save the test data of the QAM, Level, Tilt, Limit,
Hum, Scan, and Frequency spectrum tests. The Model Three has the
capability to store the amplitudes of all video and audio carriers (up to
170 channels). These data records can be captured in nonvolatile
memory and later recalled or uploaded to your PC for record keeping.
Each record carries the time, date, and other Model Three information
at the time the record is saved.
Limit Test
The Model Three can perform a complete test of all analog channels in
the selected user channel plan to specified limits at the touch of a
single key. All channels are listed with Pass or Fail results, and the
user may select any channel to review its individual test results. In
addition, results for the entire channel plan, such as Maximum
Δ
Video and Maximum
Δ
Adjacent Channel, are seen on the test-result
display.
