Szi 1029, Instead of the 800 m, Polar diagram of the szi 1029 – Sennheiser SZI 1029 User Manual
Page 5: Coverage area of the szi 1029
SZI 1029
Coverage Area and Polar Diagrams
The coverage area of the SZI 1029 and SZI 1029-10 high-power radiators depends
on the number of channels transmitted (see also “Multi-Channel Operation”).
For single-channel applications, the coverage area is up to approx. 800 m
2
for the
SZI 1029 and up to 1,600 m
2
for the -10 variant. The chapter “Practical Planning”
has already given you some basic information on the recommended number and
position of radiators. Please bear in mind that the devices radiate directionally, i.e.
reception outside the radiation angle is only possible if the signal is reflected by
walls and ceilings.
The polar diagram on the left is that of the SZI 1029. You can see that the signal-
to-noise ratio decreases the further you go away from the radiator. Eventually,
the noise becomes so loud in relation to the useful signal that the squelch in the IR
receiver mutes the audio output. A signal-to-noise ratio of 26 dB (the outer charac-
teristic in the polar diagrams) gives an intelligible but noisy signal. A signal-to-noise
ratio of > 40 dB, on the other hand, ensures a clear audio signal without the annoy-
ing noise.
To cover a room more evenly, you can mount your radiators at one point and align
them at an angle to one another. In the polar diagram on the left, two SZI 1029 have
been mounted at an angle of 40° to each other. For more information on how to
work with polar diagrams, please refer to the chapter on “Planning Theory”.
Multi-Channel Operation
All SZI 1029 models are suitable for multi-channel transmissions provided that a
suitable modulator is used. The radiator coverage area, however, decreases propor-
tionally with the number of channels the radiator is transmitting. If, for example,
your system transmits eight narrow-band channels, the radiating power is uni-
formly divided between all eight channels. The coverage area is reduced to 1/8th of
the area achieved in single-channel operation and a 5-W radiator, for example, will
cover 100 m
2
instead of the 800 m
2
in single-channel operation.
110m
100m
90m
80m
70m
60m
50m
40m
30m
20m
10m
120m
130m
140m
150m
20˚
10˚
30˚
40˚
50˚
60˚
70˚
80˚
90˚
20˚
10˚
30˚
40˚
50˚
60˚
70˚
80˚
90˚
26dB
40dB
Polar diagram of the SZI 1029*
165m
150m
135m
120m
105m
90m
75m
60m
45m
30m
15m
180m
195m
210m
225m
20˚
10˚
30˚
40˚
50˚
60˚
70˚
80˚
90˚
20˚
10˚
30˚
40˚
50˚
60˚
70˚
80˚
90˚
26dB
40dB
Polar diagram of the SZI 1029-10*
Polar diagram of two SZI 1029, mounted at an angle of
40° to each other*
110m
100m
90m
80m
70m
60m
50m
40m
30m
20m
10m
120m
130m
140m
150m
26dB
40dB
10˚
20˚
30˚
4
30˚
20˚
10˚
40°
0
200
400
600
800
12
11
10
9
8
7
6
5
4
3
2
1
Channels
m
2
Coverage area of the SZI 1029
0
m
2
400
800
1200
1600
12
11
10
9
8
7
6
5
4
3
2
1
Channels
Coverage area of the SZI 1029-10
IR Audio Transmission Technology |
Modulators/Radiators
*free field, extraneous light < 100 lx, single-channel operation