Solidyne 542 APC, Owner'S Manual

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3.9.1.1 DIAL SCAN
This tool scans the FM band in 100 KHz steps and gener-
ates a graph with the reception strength of each station.
3.9.2 Modulation Meter
Figure 27: Modulation meter
TOTAL MODULATION: Indicates the FM modulation level
measured on the tuned signal.
MODULATION MEASUREMENT RESPONSE: Measure-
ment integration time. You can change between: Instant,
125uS; 250uS; 500uS and 1mS. 125uS is recommended
for peak measurement. The appropriate integration for
measurement to have legal validity varies according to the
standards of each country.
Figure 28: Transmission parameters
PILOT: Percentage of modulation of the pilot tone. The de-
fault value is 9%.
RDS: Modulation percentage of the RDS sub-carrier. The de-
fault value is 4%.
AUDIO L/R: Audio level, indicated in dBfs.
CARRIER OFFSET: Indicates the deviation of the carrier fre-
quency, in KHz.
RDS BER (bit error ratio): This is a measure of the reception
quality of RDS data. A value of 0% indicates that no errors
were detected and 100% indicates that it is not possible to
decode the RDS data.
RDS DATA: Displays texts transmitted by RDS.
Figure 29: RDS Data (screen capture was spited for better visualization)
3.9.3 Channel separation, distortion, SNR
The 542APC allows to measure on the tuned air signal, the
channel separation and the harmonic disnoise.
These measurements provide for the set: processor;
stereo encoder; transmitter and antenna.
The measurements can be made remotely and without in-
terrupting the air emission. The Solidyne support team will
be able to access remotely to evaluate, detect and diag-
nose several aspects of the installation and the chain of
transmission.
Noise and channel separation measurements will inter-
rupt the PGM signal to play a brief audible tone (about
250 milliseconds). SNR requires to mute the PGM signal
around 2 seconds.
To run a measurement, press on "RUN new measurement" .
The results will shown on screen.
Audio Processing Core - SOLIDYNE 542 APC Page 25
Figure 30: THD and Channel separation