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TELE-audiovision International — The World‘s Leading Digital TV Industry Publication

— 03-04/2015

TELE-audiovision.com

DVB-S

Measurement

80. Even though the signal was

very weak we were able to watch

the live feed of this football

transmission. Note how narrow

the transponder’s bandwidth is

in the spectrum.

81. This transponder only carries

a single channel, and obviously

the Spaun Sparos 711 is able to

display all available details.

82. Technicians who take care

of head-ends need to be able to

look up all PID values.

83. The Spaun Sparos 711 is able

to present the entire content of

the Network Information Table

(NIT). Unfortunately, many

providers don’t put a lot of

effort into correctly entering all

required details, even though we

generally believe this to be an

important function.

84. Here we can see children

playing football. This feed comes

with PAL resolution and MPEG-2

compression.

85. It goes without saying that

the Spaun Sparos 711can pre-

sent a constellation diagram for

all supported modulations. Here

we can see the constellation

diagram of the less-than-perfect

transponder with the live feed.

Transponder Lists

86. If you want to create a new

transponder list it is best to

launch a transponder search.

Give an appropriate name to

the list or use the default name

AUTOSET.

87. The name can easily be

edited thanks to the virtual key-

board on the touchscreen.

88. If required, additional

parameters (e.g. for the correct

addressing of multiswitches)

can be entered before the search

starts.

89. All detected parameters can

be manually edited at any time.

Here we enter the correct satel-

lite name.

90. The transponder list logic is

easy to follow: On the one hand

there is a library for up to 1000

transponders. All transponders

that are found in a search are

added to this library. In addition,

there are lists, with each additi-

onal search creating a dedicated

list. Those lists can be edited in

case you want to delete existing

transponders or add transpon-

ders from the library. The type of

modulation does not matter here

at all. Parameters of individual

transponders can be edited in

the library.

91. Lists that are set up this way

can then be used for automatic

measurement protocols.

Attenuators

92. The Spaun Sparos 711 is

perfectly suited for testing

attenuators. First, we measured

a DVB-C transponder without

attenuator.

93. Next, we connected the first

5 dB attenuator, which caused

the signal level to decrease

from 71.5 dBμV to 69.1 dBμV.

As we had assumed, a measu-

rement with the Spaun Sparos

711 confirmed that something

was wrong with this particular

component.

94. When we cascaded a second

attenuator the signal went down

from 69.1 dBμV to 64.7 dBμV.

This means that the second

attenuator worked as intended

and causes signal attenuation

by 4.4 dB.

95. Finally, we added a third

attenuator, which reduced the

signal level further from 64.7

dBμV to 59.2 dBμV. So the

measurement confirmed that

the third attenuator also worked

according to specifications with

its 5.5 dB attenuation.

Spaun handles all data and

files, and there are no strange

proprietary binary file formats

for transponder and protocol

lists that can only be used

with special software (that

frequently comes at a charge).

Instead, you are served up

conventional CSV files, which

can easily be opened with MS

Excel or similar software. And

if you are blessed with pro-

gramming skills you may even

compile your own tailor-made

editor. On the whole, this is

a genuinely exemplary ap-

proach that allows integrating

the meter into a company’s