UNAOHM EP2500 - Measurement Demodulator Selection; Audio Signal Reception; Audio Monitor; Aural Duplication of Signal Level or DCP Measurement

UNAOHM
28 EP2500 (Rev. 0)
Measure
1740 SC0:6.50 pr 00
MORE 13V 22k C M 20
BW W
DEM TV
SPEC
TV
50.5 dBuV
Figure 11 Measurement display
7.15.1 Measurement Demodulator Selection
In order to be accurately measured each type of signal, must be properly demodulated. The instrument
offers three demodulators, which may be selected by means of key DEM:
1. TV. Peak detector for TV signals, optimised for both negative (B/G, D/K standards, etc.) and
positive modulations (L standard). It allows the audio subcarrier to be received by tuning in the
video carrier of an analogue TV channel.
2. FM. Optimised for FM modulations, such as the audio of the B/G, etc. television standards, or the
FM radio transmissions.
3. AM. Average value detector, optimised for amplitude modulated signals as, for example, the audio
of the French channels.
7.15.2 Audio Signal Reception
The instrument demodulates the audio subcarrier of the tuned channel when in the TV mode or, if the
TV demodulator is selected, in the measurement mode.
In the terrestrial band the audio subcarrier of the TV-standard selected is automatically tuned, while in
the satellite band the following procedure should be followed:
1. Press SOUND SAT (22). In the lower section of the OSD SC for sound carrier will be indicated
together with the number 0 or 1, corresponding to one of the two storable subcarriers.
2. Select one of the subcarriers by means of the Shaft Encoder.
3. To change the tuning press SOUND SAT then tune in the desired frequency by means of the Shaft
Encoder or the numerical keypad (8).
4. Press ↵ ENTER to confirm only.
5. Press SOUND SAT again to confirm and return to the normal operational mode.
The audio satellite bandwidth and deemphasis are programmed in the main menu (Chap. 8).
7.15.3 Audio Monitor
In measurement mode, the audio of the instrument functions like a TV, AM, or FM (as selected)
demodulator monitor.
7.15.4 Aural Duplication of Signal Level or DCP Measurement
There are circumstances when it is very difficult, if not actually impossible, to read the display or view
the data displayed on the screen of the instrument. Consider, for example dish peaking. With it, it is very
useful to engage the aural duplication of the signal level (or DCP) being received.