Measuring The Level Of Analogue Signals - Promax MC-377+ Instruction Manual

INSTRUCTION MANUAL MC-377+.

4.2.6.1 Measuring the level of analogue signals

To measure the level of an analogue signal, proceed as described below:
- Select the Spectrum Analyser operating mode, SPAN mode, and with the help
of the frequency counter display [22] tune the signal using the TUNING [24] and
FINE TUNING controls [26]. Adjust the SPAN control [23] to select a bandwidth
so that the signal occupies the most part of the image. If you are dealing with a
television signal it is also possible to take the measurement from the Monitor
mode (in this case press the audio control [27] so that the measurement bar
appears at the top of the image).
- Select the measurement scale for analogue signals LEVEL [33], in order to do
this the DIG key [11] should be released and the ANALOG indicator [31] should
remain lit.
- Read the level on the screen with the help of the scale calibrated in dBµV (20-
80 dBµV) LEVEL [33]. If the level is very close to 80 dBµV or is greater than this
value, the signal should be attenuated using the RF attenuators.
On terrestrial bands the [14] 10 dB, [15] 20 dB and [16] 20 dB attenuation
keys must be pressed in order to obtain the signal level into the scale. The
total attenuation is the addition of the keys pressed.
On the satellite band the [16] 20 dB attenuation key must be pressed.
- The actual signal level is calculated in the following manner:
Level [dBµV] = Reading [dBµV] + Attenuation [dB] + Correction Factor [dB]
THE CORRECTION FACTOR IS OBTAINED FROM THE CORRECTION CHART
WHICH IS DELIVERED WITH THE INSTRUMENT. THIS VALUE DEPENDS ON THE
FREQUENCY.
Page 24
VERY IMPORTANT
May 2001