testrapport digitale kabelmeter satcatcher digipro c max...

34 35TELE-satellite International — The World‘s Largest Digital TV Trade Magazine — 02-03/2012 — www.TELE-satellite.com www.TELE-satellite.com — 02-03/2012 — TELE-satellite International — The World‘s Largest Digital TV Trade Magazine

SatCatcher Digipro C Max Professional

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Digitale kabelmeter TeSTraPPorT

02-03/2012

36 TELE-satellite International — The World‘s Largest Digital TV Trade Magazine — 02-03/2012 — www.TELE-satellite.com

Satcatcher Digipro C MaxMore than a cable meter: includes everything a professional installer needs

an accurate Instrument With Many accessories

Accuracy is something that every installer will value with a signal meter but apart from that true professional users have

further demands on a me-ter: the instrument should have a bright and readable display, and its keyboard should be easy to oper-

TeST rePorT Digital Cable Meter

ate. It should also offer a wide choice of accessories making the work simpler and more efficient. To our delight, the new Digipro C Max by Satcatcher fulfills all those requirements. Its display is exceptionally bright and clear, you can operate its keyboard even with gloves on your hands, and the number of accesso-ries they offer to the pro-fessional user is really sur-prising.

The meter can be sup-plied packaged in two ways. In a metal box like other Satcatcher meters or in a premium package with lots of extras included. For our test we opted for the latter and were delighted at the many useful accessories. The most unusual and most useful for an installer is a fully adjustable vest with a lot of pockets and straps. It allows you not only to transport and use the me-ter in a convenient way but also to keep handy all sorts of other tools an installer must have. Apart for the vest, you get a plug type power supply, a car lighter DC charger, a neck strap with a piece of sheep skin fur to avoid skin irritation, and a bad weather cover for the meter along with an attachable sun shade. Everything is neatly packed in a carrying bag so you do not need to worry that your meter accessories will disappear somewhere over time.

The workmanship of the Digipro C Max is very good. The enclosure is robust but quite elegant at the same

time. Buttons are large and clearly labeled. The POWER button has an edg-ing around it what guar-antees that the meter will not switch on accidentally when pressed against a solid surface. The keyboard consists of a numeric key-pad, quick access buttons, navigational arrows and 4 function keys F1 - F4. The function of these F1 – F4 buttons depends on the particular menu or screen you arrived at and is always explained at the bottom of the display window. Speak-ing of the display, it is one of the strongest points of this meter. This TFT LCD It is very bright and clear. You will be able to read it even outside in a very sunny day. There is also a loudspeaker embedded in the Digipro C Max Professional, giving off a significant sound volume.

The Digipro C-Max Pro-fessional lets you either use a pre-programmed chan-nel band plan or you may choose to blindscan the whole bandwidth. The effort you put into the initial chan-nel band plan programming will pay off in much quicker measurements. To create a band plan, you enter the Meter Config menu and se-lect Edit Channel item. In this screen, you edit the channel name (most of the installers would probably use the standard chan-nel designators like: S02, S28, K32), its kind (analog or digital), and a number of parameters as: frequen-cies, modulation, symbol rate, bandwidth. Of course there is a different set of

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parameters for analog and for digital channel. In this way, you edit channel by channel and save them in the meter’s memory. Such a list of the channels that are present in a given ca-ble network is called a band plan of this network. Once you have created a cor-rect band plan for the ca-ble systems you are about to install and measure, you can enter the Auto Meas-ure menu item and make the meter measure every channel form the list one by one.

However, it is also pos-sible to scan an unknown network. In such case, the Digipro C-Max does a smart thing: it recognizes fully automatically all analog channels as well as the QAM modes and symbolrates for the digital DVB-C channels. For analog TV channels it shows the video and audio frequencies along with their signal levels and S/N ratio. The measurement results screen for a DVB-C signal is naturally more complex. You get not only signal fre-quency, QAM order, sym-bol rate, channel power, modulation error ratio (MER) and carrier-to-noise (C/N) readings but also a graphic representation of the constellation diagram. By pressing a button you can enlarge the diagram. This is perfect to asses the signal quality visually: the tighter the green dots’ con-centration in the center of the squares, the less noisy the signal is. Of course,

visual assessment is rather subjective and not very ac-curate, therefore there are MER and C/N readings that correspond to the quality of the digital signal.

Furthermore, the Digipro C-Max offers a spectrum view. It produces a clean picture of the frequency spectrum with adjustable span and amplitude. You can set the following fre-quency spans: FULL, 500, 200, 100, 50, 32, 16, and 8 MHz. Maximum amplitude can be set from 60 to 120 dBµV in 10 dBµV steps. Di-gipro C-Max creates a very readable spectrum picture. It does not take long to scan the whole bandwidth.

Even the best looking meter, and Digipro C-Max looks great indeed, would not be worth its price if its measurement results were improbable. Therefore, we compared the results pro-duced by the Digipro C-Max with another high class ref-erence meter. We are de-lighted to announce that the results were in perfect agreement. Please exam-ine Table 1 and Table 2. Both for digital and analog TV signals, the channel power results were prac-tically identical. Also the MER measurements were matching one another very well indeed. The only differ-ences we noted in the S/N measurements, this, how-ever, is common between different meter brands. That’s because S/N meas-urements depend on the particular frequency a me-

ter takes as a noise refer-ence level. As a result, S/N and C/N can be compared only if measured with the same meter model but not when measured with dif-ferent models and makes. MER is a much better sig-nal quality indicator as this value can be measured with different meters and you can expect similar results with any product. Our gen-eral conclusion: Digipro C-Max is a very accurate me-ter and you can fully rely on its signal strength and MER measurements.

A great highlight is an-other positive feature: the Digipro C-Max not only takes measurements but it can also play back digital channel video and audio. Once it locks to the signal, it searches the NIT table inside the transport stream and based on the informa-tions found there, the me-ter displays a list of TV and radio channels. The last re-maining step is to select the channel you want to watch and press a button. Of course, this works only for FTA channels as the meter does not have any CI slot or smart card reader and can not descramble PayTV channels. The Digipro C-Max does not display analog TV channels either but tak-ing into account how fast the technology advances, analog channels will disap-pear from CATV networks anyway quite soon. So this is not something to care about.

Finally we come to a truel-

TeLe-satellite expert Jacek Pawlowski wears the installer's vest from Satcatcher. The vest offers multiple pockets for the installer - and even matches the Digipro C-Max protective case' color!

Table 1. Digital TV signal measurement resultsPower [dBµV] Mer [dB]

Signal C-Max Ref C-Max Ref256QaM 474 MHz 87,1 87,7 38,8 36,764QaM 474 MHz 87,1 87,7 37,9 36,8256QaM 674 MHz 82,5 83 39,4 35,664QaM 674 MHz 82,6 82,8 38,7 35,4

Table 2. analog TV signal measurement resultsPower [dBµV] S/N [dB]

Signal C-Max Ref C-Max RefVideo 471,25 MHz 61,3 64,4 23,7 48,6audio 477,75 MHz 50,4 52Video 576,25 MHz 64 63,7 26,1 17,7audio 581,75 MHz 50,3 49,8

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1. Main menu2. Channel measure3. Tilt measurement screen4. DVB-C signal shown in spectrum view5. Configuration menu6. Band plans7. one of the preprogrammed and plans8. editing a channel in a band plan9. options menu10. Identifying digital TV signal chosen in the spectrum view11. 256QaM constellation and signal measurement results12. Closer examination of the constellation allows you to visually asses signal quality13. Meter searches NIT in DVB-C signal to create a channel list14. Channel list of the selected DVB-C carrier15. Meter displays channel video like a small TV-set16. a mix of analog and digital TV signal in a real cable network17. analog TV signals18. Digital TV signals19. Detecting the parameters of digital carrier

DaTaTeCHNICaL

Manufacturer SatCatcher Ltd, Unit 7, Salvesen Way, Hull, East Yorkshire, HU3 4UQ, UNITED KINGDOM

Webpage www.satcatcher.com

e-mail [email protected]

Tel +44-1652-408191

Model Digipro C Max

Function Digital and analog cable TV meter

Input frequency range 46 MHz - 862 MHz for digital TV 46 MHz – 870 MHz for analog TV

Input signal level range 40dBuV - 110dBuV for digital TV 25dBuV – 120dBuV for analog TV

accuracy of level measurement 2 dB for digital TV 1.5 dB for analog TV

DVB-C symbol rates 1 – 7 Ms/sec

Modulation 16/32 /64/128/256QAM

Digital TV standard DVB-C/ITU-T J.83-ANNEX A/B/C

Channel bandwidth 4, 8, 20, 40 MHz, USA version: 6 instead of 8 MHz

Working time when fully charged 4 – 5 hours

Jacek PawlowskiTELE-satellite

Test CenterPoland

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42 TELE-satellite International — The World‘s Largest Digital TV Trade Magazine — 02-03/2012 — www.TELE-satellite.com

exceptionally accurateVery bright and clear displaya lot of useful accessoriesUSB application available for editing band plan

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expert opinion

ly valuable function of the meter, which is so useful for the professional install-er: the tilt measurement. Up to ten channels can be selected for this. Usually, you would select channels evenly distributed over the whole frequency range. Of course, the selected chan-nels must carry a TV signal. You first measure those channels in the TILT Meas-ure submenu somewhere in the beginning of the cable network, where all the sig-nals are strong and rela-tively equal in amplitude. then you press the REF but-ton to store those channels’

levels as reference. Then you move to various other points of the network and repeat this measurement. You will see the difference expressed in decibels be-tween the reference level and the current level for every channel.

The tilt measurement al-lows you to quickly iden-tify signal level differences over a specified frequency range. Then all you do is insert an attenuator or an equalizar in order to smoothen the differenc-es according to the cable system’s specifications. Thanks to this, you can

easily find out if the cabling along with the distribution equipment does not intro-duce excessive attenuation in particular parts of the cable TV frequency range.

We found the Digipro C-Max to be a very mature meter, offering to the in-

staller all the features he needs to properly align a cable system. The accu-racy of the meter matches our professional reference meters and the accesso-ries made available by Sat-cacther are an additional value to the installer.

testrapport digitale kabelmeter satcatcher digipro c max...

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