Promax MC-377+ Manual De Instrucciones página 71

INSTRUCTION MANUAL MC-377+.
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 [33].
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] = Readout (69 dBµV) + Atten. (10 dB) + Correct. factor (-1 dB) = 78 dBµV
May 2001
Figure 8.- Example of correction chart.
Measurement conditions:
Video carrier freq.: 551.25 MHz
RF attenuation: 10 dB
Mode: ANALOG
Page 25