FEATURE Upgrade for 8dtek Satellite MetersWaterfall • Detection of weak signals • Identification of all active satellitesDiagrams for • Allows for highly precise antenna alignment • Long-term measurements for reliable feed detection8dtek Satellite • Ideal upgrade for 8dtek satellite metersMeters TELE-satellite Magazine Business Voucher www.TELE-satellite.info/12/01/8dtek-waterfall Direct Contact to Sales Manager232 TELE-satellite International — The World‘s Largest Digital TV Trade Magazine — 12-01/2012 — www.TELE-satellite.com www.TELE-satellite.com — 12-01/2012 — TELE-satellite International — The World‘s Largest Digital TV Trade Magazine 233
FEATURE Upgrade for 8dtek Satellite MetersUnconventional thinkingturns 8dtek satellitemeters into genuinelyprofessional tools – withoutcosting a penny!Vitor Martins Augusto Satellite meters and satellite finders months a number of new satellite me- diagram is drawn up line by line fromare used to professionally align satellite ters with spectrum analyzer have been top to bottom, with each line describingantennas and to identify flaws in an ex- launched. These analyzers are de- a full spectrum. Actually, this is how theisting setup. True satellite enthusiasts, signed to display the current signal sit- name was derived: Like in a waterfall,however, also have additional purposes uation – but what do you do if you need information flows from top to bottom.for meters: Satellite DXers are per- to monitor a specific signal for a certainmanently on the hunt for weak or rare length of time? This may be necessary We wanted to provide proof that asignals, while feed hunters are on the when you rotate a motorised antenna, waterfall diagram can actually work forlookout for undocumented transmis- for manually aligning an antenna or for satellite meters as well and to that endsions (feeds). performing a long-term measurement. we used three different 8dtek satel- lite meters: Xtra-S, Gifted and Desired Both target groups prefer satellite In ham radio circles a so-called wa- (please refer to TELE-satellite issuesmeters with spectrum analyzers, be- terfall diagram is used for exactly those 06-07/2011 and 08-09/2011 for testcause with the help of a satellite spec- purposes: It shows the spectrum over a reports about these devices). They aretrum it becomes possible to spot a sat- period of time using the three parame- absolute exceptions in their price seg-ellite long before a satellite receiver is ters of frequency, signal level and time. ment as all of them offer a functionalcapable of locking a signal. In addition, This would actually require a three-di- spectrum analyzer.a spectrum display helps to identify and mensional diagram, something that cananalyze transponders. It is even possi- only be achieved with great effort. In It’s rather striking to discover that theble to find out whether new transpond- order to display all required information manufacturer decided to focus on ei-ers have become active at short notice, without having to do 3D calculations, ther speed or display resolution: Whilewhich in many cases hints at new feeds. one parameter (signal level in our case) the 8dtek Xtra-S boasts a real-timeReal-time spectrums are the display of is colour-coded. spectrum display – albeit at low resolu-choice for those satellite enthusiasts, tion – the Gifted and Desired modelsas they have a refresh rate of way less So in a waterfall diagram the x-ax- impress with high-resolution displays atthan one second. is refers to frequency and the y-axis the cost of display build-up time. shows time as well as – in a gradual col- Hence it’s no surprise that in recent our scheme – signal level. A waterfall All three models feature a video out-■ Image 1: The three satellite meters Desired, Xtra-S and Gifted frommanufacturer 8dtek were at our disposal for experimenting. 1234 TELE-satellite International — The World‘s Largest Digital TV Trade Magazine — 12-01/2012 — www.TELE-satellite.com
2 6 put which creates a composite video of the waterfall diagram corresponds signal of the spectrum display. to a spectrum measurement after ten minutes each. This allows documenting We took advantage of that option to the entire frequency range of a satellite save the video signal on our PC with over a period of 24 hours. The individu- the help of a video card, and to extract al colours indicate any signal deviation spectrum measurements using image across the entire spectrum. processing software in order to further work with the data. Looking at the Xtra-S, Gifted and De- sired satellite meters by manufacturer All you need for this is a so-called 8dtek from many different perspectives3 video grabber, which is an adapter that our respect and admiration for those digitises the analog video signal and neat devices was growing all the time. creates a file for further software pro- It’s hard to believe how many features cessing. In theory, any TV card or USB this is shown with a time element and models cannot be used for creating wa- and functions can be packed into such adapter should do – USB adapters are since it is always possible to compare terfall diagrams to document antenna small meters. Battery life also never frequently available in a bundle with any current value with preceding val- alignment and rotation. For long-term failed to impress: Three to four hours video editors to digitise VHS tapes. You ues finding the perfect alignment be- measurement, on the other hand, they Image 2: This EasyCAP video grabber was may even want to look for the ‘EasyCap’ comes child’s play. In the lower image are perfect. Such measurements are bought on eBay for approximately 5 EUR. adapter on eBay, which we were able to segment you can easily see for yourself primarily performed to find out if or Image 3: The waterfall diagram shows obtain from Hong Kong for about EUR how strong the signal is with perfect why a signal has occasional errors. changes during rotation of a motorised 5.00 including postage (see image 2). antenna alignment. antenna from 30.0W to 45.0E. All satellites between these two stop positions are Image 6 presents the result of a clearly indicated. For our experiment we proceeded For real-time measurement the 8dtek long-term measurement focusing on Image 4: Fine-tuning of the antenna with programming software that con- Xtra-S turned out to be a perfect com- two transponders on HISPASAT. No er- alignment towards HISPASAT 30.0W. verts, analyses and extracts the spec- panion. The spectrum builds up very rors can be seen on this measurement, Image 5: Long-term measurement of quickly on this meter, which is a huge since only a period of one minute was ASTRA 19.2E using the Desired satellite trum using a video grabber, so that meter. This is where the device’s high- data can be displayed as a waterfall benefit. Unfortunately, however, the analysed. With our software it is of resolution display comes to the fore.4 diagram. TELE-satellite readers can display resolution is rather low, as can course possible to vastly extend that Image 6: Long-term monitoring of two download the software free of charge be seen on images 3 and 4. 8dtek went period – all you need to do is select a transponders. (www.TELE-satellite.com/waterfall-for- for higher resolutions with their Gifted time between one second and ten min- Image 7: Set-up with small motorised antenna. Due to lack of DiSEqC 1.2 8dtek.zip) so that users of any of the and Desired models, although at re- utes instead of real-time. If you select support of the Xtra-S it was rotated using three 8dtek meters can add waterfall duced speed. This is why those two ten minutes, for example, every line the button on the motor itself. capability to their devices. Waterfall diagrams can be hugely useful: After a short adjustment period we discovered a number of scenarios in which waterfalls diagrams can be put to fruitful use. Have a look at image 3, for example, to find out how our motorised antenna moves from HIPASAT 30.0W to INTELSAT12 45.0E. The waterfall dia- gram shows all passed satellites, which is an easy way of checking whether all5 positions are already stored in the sat- ellite receiver. Image 4 shows a rather different ap- plication for a waterfall diagram. In this scenario the antenna alignment (HIS- PASAT 30.0W in our case) is optimised. While a conventional spectrum display can be used to perfectly align an an- tenna using the peak level feature, a waterfall diagram can achieve the same result with much less hassle. Seen from top to bottom the weak red colours show somewhat mediocre reception quality of HISPASAT. When the antenna is moved slightly towards the East the signal becomes weaker, which is why the antenna is then ro- tated in the opposite direction with the signal becoming stronger, reaching its peak level and decreasing again. All 7236 TELE-satellite International — The World‘s Largest Digital TV Trade Magazine — 12-01/2012 — www.TELE-satellite.com www.TELE-satellite.com — 12-01/2012 — TELE-satellite International — The World‘s Largest Digital TV Trade Magazine 237
of continuous use was the rule rather age 8). In the window that pops up you video grabbers may not be set up for than the exception. choose your TV card or the video grab- PAL by default, but for NTSC or SECAM ber. Please bear in mind that many lap- instead – in such cases you need to Have we raised your interest? Simply top computers will also list the built-in run the software that comes with your go to www.TELE-satellite.com/water- camera here. video grabber and change to PAL video fall-for-8dtek.zip to download our soft- mode. Finally, you select your 8dtek ware from the TELE-satellite server. Of Next, you select the video format model (image 10) and press START to course you also need an 8dtek satellite (image 9). Depending on the TV card initiate the waterfall diagram. Due to meter as well as a TV card or USB video or video grabber various options may implementation of the video function grabber. be available; the only thing you need to you need to press STOP if you want to make sure is to select 720x576 pixels copy the image using PRTSC. Once the software is set up you first (full PAL resolution). The software does need to select your video source (im- not support any other resolution! Some Happy experimenting!8 910 Image 8: Selecting video source. Image 9: Selecting video format. Image 10: Selecting 8dtek model. Image 11: Second test set-up, this time using a netbook and the Desired. Long-term measurement tests were carried out with this equipment.11 238 TELE-satellite International — The World‘s Largest Digital TV Trade Magazine — 12-01/2012 — www.TELE-satellite.com
A particular slide catching your eye?
Clipping is a handy way to collect important slides you want to go back to later.