Test Functions - Promax MO-170 Manual De Instrucciones

USER'S MANUAL. MO-170
Fine Adjust: Select this function to program the RF output reference level. For a
correct reference, adjust the output attenuation to 0 dB, before the fine adjustment.
Changes are also applied in real time. Turning the knob CW increases the output
level. Turn it CCW decreases the level.
The displayed characters are integer numbers. The range goes from a maximum
attenuation of —31 to a minimum attennuation of +31 (i.e. 0 to 63 attenuation steps).
To exit this function, press the MENU or encoder keys.

4.7 TEST functions

This menu contains a series of parameters used to correctly carry out all types of
transmission tests using the MO-170 modulator.
MODE: Selects the test to be carried out. Available options are:
NONE: Normal COFDM output.
CBER: Inject channel bit errors to obtain a non-zero BER before the
Viterbi decoder (Channel BER).
VBER: Inject bit errors to obtain a non-zero BER after the Viterbi decoder
(Viterbi BER or simply BER).
Blank carriers: Blank carriers starting at index Start Carrier and ending
at index Stop Carrier (see below).
Pilots only: Generate a DVB-T signal containing pilot carriers only
(continual and TPS).
PRBS/TR 290: Replace the input to the constellation mapper with a
PRBS sequence of length 2
specified in document ETSI TR 101 290.
The following two parameters select the carrier interval to blank, in order to make
measurements of intermodulation noise and/or quantisation noise within the channel.
Start Carrier: Selects the initial index (from 0 to 1704 in 2K, 0 to 6816 in 8k) of
the first carrier to blank within the COFDM ensemble.
Stop Carrier: Selects the final index (from 0 to 1704 in 2k, 0 to 6816 in 8k) of
the last carrier to blank within the COFDM ensemble.
12/2006
15
-1 or 2²³-1(see PBRS bits entry above) as
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