Promax 10 SE, Руководство пользователя

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USER’S MANUAL. PROMAX-10 Premium
11/2008 Page 3
En
g
lis
h
LEVEL MEASUREMENT
Measurement
Analogue channels Video carrier level measurement.
Digital channels Power measurement in the channel bandwidth by
integration method.
Measuring range
From 25 to 120 dB
µ
V. (From -35 dBmV to
60 dBmV)
( ) 2
.
Maximum input level
From 5 to 863 MHz 120 dB
µ
V. (60 dBmV
(2)
).
DC to 60 Hz 60 V DC or RMS
Reduction of the measurement range depending on the number of channels.
Up to 10 channels 110 dB
µ
V.
From 11 to 20 channels 107 dB
µ
V.
From 21 to 50 channels 103 dB
µ
V.
From 51 to 80 channels 101 dB
µ
V.
Readout Digital in dBµV, dBmV or dBm and analogue
through a graphic bar. 1 dB resolution.
IF bandwidth 200 kHz
±
30kHz.
Input impedance 75
Ω
.
Audible indicator Tone which varies with the signal level.
Accuracy
Analogue channels
±
2 dB (from 0 to 40
°
C) for negative video
modulation
( ) 3
.
Digital channels
±
3 dB (from 0 to 40
°
C) for 8 MHz bandwidth
channels.
DIGITAL SIGNALS MEASUREMENT
MER (Modulation error ratio)
Measurement range 22 dB to 34 dB for 64 QAM.
Accuracy
±
2 dB.
BER (Bit error rate)
Measured before RS decoding
Measurement range 10 E-2 to 10 E-8.
Constellation Diagram DVB-QAM signals (Annex A/B/C) and DOCSIS /
Euro-DOCSIS.
Lock range -10 dBmV to 60 dBmV.
Symbol rate
Measurement range 1000 to 7200 Msym/s
( ) 4
for 16/64/256 QAM.
2
Because of safety reasons, the maximum input power over the entire band is limited up to 120 dBµV. The
equivalent power level for a group of channels of similar levels is related with the input power level over the entire
band according to the following expression:
L
T
= L+10 log N (L
T
: total level , L: mean level of one channel, N: number of channels present).
For higher input power levels, the use of an external attenuator of 20 dB is recommended.
There may be certain frequencies where the symbol "<" appears at levels higher than 25 dBµV (maximum 28 dB).
This is due to the automatic correction of the frequency response.
The value measured remains correct, although the accuracy becomes ±3 dB
3
For the positive video modulation (L standard) it can vary from 0 to -2 dB among white and black image.
4
Including the OP-010-E option, otherwise the margin is from 1000 to 7000.