Promax MC-577 Manual De Instrucciones página 66

EXAMPLE A. Measuring the level of an analogue signal
Take the following figure as an example, showing a television channel: the lower
part of the spectrum shows the lobe corresponding to the video carrier ( 69 dBµV ) and in
the upper part you can see the audio carrier (63 dBµV) preceded by the chrominance
signal (40 dBµV). Note that the measurements are taken on the LEVEL scale [34].
Figure 7.- Example of analogue signal level measurement.
We assume that the instrument was delivered with the following Correction Chart:
From the correction chart you find that the Correction Factor to be applied to the
frequency you are working with (551.25 MHz) is -1 dB . Therefore, the actual signal level
is:
Level [dBµV] = Measurement ( 69 dBµV ) + Atten. ( 10 dB ) + Correct. factor ( -1 dB ) = 78 dBµV
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Figure 8.- Example of correction chart.
USER'S MANUAL MC-577.
Measurement conditions:
Video carrier freq.: 551.25 MHz
RF attenuation:
Mode:
10 dB
ANALOG
05/2003