Digital sound level meter with data logger (22 pages)
Summary of Contents for SEFRAM 7848
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– 7848 – 7848 FIELD STRENGHT METERS USER MANUAL This product contains one or more programs protected under international and US copyright laws as un- published works. They are confidential and proprietary to Dolby laboratories. Their reproduction or disclo- sure, in whole or in part, or the production of derivative works there from without the express permission of Dolby Laboratories is prohibited.
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– 7848 – Revision follow-up Version / Date Modified chapters Nature of modification 1.0 / July 2015 Creation of the document 2.0 / October 2015 Guarantee Information about spare parts added Terrestrial remote supply added. 17.3 Terrestrial remote supply specification added 3.0 / November 2015...
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– 7848 – Thank you for purchasing this SEFRAM product and therefore trusting our company. Our different teams (research department, production, sales department, after-sales service…) are aiming at satisfying your wishes by designing and updating very advanced appliances. To obtain the best performance from this product please read this manual carefully.
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It shall subscribe, at its own expenses, any insurance required for the transport. The SEFRAM company reserves the right to refuse any product wrongly conditioned and not to take in charge any break con- secutive to the transport.
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March 1, 2015: Spare parts are not available to the consumer. SEFRAM offers the supply of spare parts during repair by its service. Consumable parts are provided according to the legislation applicable to them (case of batteries).
– 7848 – TABLE OF CONTENTS Important information ......................9 Particular precautions ............................. 9 Security instructions ............................9 Symbols and definitions ..........................9 Conformity and restrictions of the appliance ....................10 Quick start-up ........................11 Presentation of the appliance ........................11 Signal spotting ..............................
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– 7848 – Terrestrial check: ............................40 Autoset : ............................... 43 Measures – TV – Spectrum:......................... 45 7.3.1 AutoLock function..........................46 Terrestrial setup: ............................46 Creation or modification of setups in the library ................... 47 Echo / Guard interval: ........................... 48 Configuration: ...............................
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– 7848 – 17.1 Technical specifications ..........................78 17.2 Digital measurements ..........................79 17.3 Divers ................................ 80 17.1 General specifications ..........................81 17.2 Accessories .............................. 81 17.3 Typical values for measurements ......................81 18 CE Declaration ........................82...
In case of failure or for the maintenance of the appliance, only a qualified personal shall be entitled to work on it. In such a case, it is required to use Sefram spare parts. Do not open the appliance: risk of electric shock.
– 7848 – Symbols on the appliance: Attention: Refer to the manual. Shows a risk of damage for the material connected to the in- strument or to the instrument itself. Ground: Grounded accessible parts. Product for recycling. Conformity and restrictions of the appliance...
Pour brancher le signal à analyser Important keys: The 7848 is an appliance with a capacitive touchscreen. This requires a soft handling. No glove and no sty- lus should be used, so that the triggering should be taken into account.
In this case, the Autoset function allows a scan of the channels that the antenna detects. Plug the cable of your antenna to the 7848 (take care to use an adequate adaptor) Turn on your appliance, then select terrestrial mode : The Home page appears on screen.
– 7848 – Press START. The appliance searches until the end of the scan and turns directly to the Measures page. If no channel has been found, see the next chapter. On this new page, press Prog, select the channel that you want to display. Then you can press TV key to watch the image of the signal.
– 7848 – 2.2.2.1 Use of the spectrum Plug the cable of your antenna to the 7848 (take care to use an adequate adaptor) Turn your appliance on. Press the Measures-TV-Spectrum key Press the Spectrum touch: Access to full SPAN mode...
– 7848 – You can now display the level, the BER/MER of the signal selected on the same page by pressing the key. 2.2.2.2 Use of the Antenna pointing The appliance gets an antenna pointing mode in order to regulate quickly and easily your terrestrial antenna.
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Enter 4 frequencies of the emitter you want to check. You can find many different French transmitters in an Excel file available on the website of SEFRAM (download section, then database transmitters TNT) or by clicking under the following link: http://www.sefram.com/Maj_soft/Canaux_TNT_France_2015.xls...
– 7848 – No transmitter found, bad reception quality → red smiley Average reception quality (< 50%) → orange smiley Good reception quality (> 50%) → green smiley 2.2.3 Installation of a satellite dish Connect the satellite dish to the appliance.
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– 7848 – Select a satelllite like in the example below (here Astra1): Slowly orientate the satellite dish until hearing the locking melody and getting the best quality No found transponder → red smiley Average reception quality (< 50%) → orange smiley Good reception quality (>...
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– 7848 – Attention: The displayed name depends on the content of the MPEG NIT table. Some distributors provide no (or poor) such table. The displayed information may be wrong. Attention: To identify a satellite, you must be locked on all 4 transponders. (Quality > 0) However, some transponders are regularly modified.
3 Presentation General -The field strength meter 7848 is an appliance designed for the installation and maintenance of any broad- casting and reception installations of analogical and digital terrestrial television channels or satellites. - The band ranges between 45 MHz and 2200 MHz; this allows accurate measurements on all analogical television standards, FM carrier waves and the various digital standards DVB-T/T2, DVB-S/S2, DSS.
– 7848 – Description of the appliance 7’’ capaci- tive Fas- touchscre tening for en high straps resolution RF socket with F/F adapt- Remote supply light Ethernet socket USB A socket Bouton MARCHE/ARRET Charging indicator light External power socket 15 V 5 A max...
Battery Attention: Any intervention on the battery requires the disassembly of the appliance and should be made by a SEFRAM technician. Use only batteries provided by SEFRAM. Security advice: Do not throw into the fire or heat up the battery pack ...
– 7848 – Charge the device only when the device is off. Charge the device only with the provided power supply block. The battery is 80%-loaded after 1 hour 50 minutes. The total charge is reached after 2 hours 30 minutes.
5 Man-machine interface Content of the screen 7848 is an appliance with a capacitive touchscreen. This requires a soft handling. No glove and no stylus should be used, so that the triggering should be taken into account. You will recognize the « keys » by their dark grey color (example: the home key: You can also select lines in tables.
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– 7848 – The Home page allows the navigation through all functions of the appliance: HOME Page in terrestrial mode HOME Page in satellite mode On all pages, we have this informations: Indication of the values Indication of the position of the...
– 7848 – To navigate through a table inside a page or a window, a vertical slide appears with arrows to move up and down the table. To move faster, you can slide a cursor with your fingers. Move up through...
– 7848 – 5.2.2 Change with selection When pressing a key, you may have a window with multiple choice. You only have to press the value you want to validate it. This key allows you to cancel and exit this window, like in the example below: In this example, the bandwidth changes from 8 to 6 MHz: 5.2.3...
– 7848 – List of setups In order to make easier the recall of data on field, the appliance uses 500 setups in satellite and 500 setups in terrestrial. Example of list of terrestrial setup Example of list of satellite setup A setup is made of: ...
– 7848 – 6 SATELLITE mode When the satellite mode is selected, a message appears with the request of starting Remote power supply of the satellite dish: Once the TV supply activated or not, the HOME page of the satellite mode appears:...
– 7848 – Check Sat: Press to access Check Sat mode. Name and position of the satellite Global quality indi- cation Frequency, polarization, band, level and quality The appliance has 32 possible orbital positions for satellites. It is provided with near of 10 satellites regis- tered.
– 7848 – 6.1.1 Updating satellite You can update frequencies of the checks sat by consulting the file PDF posted on-line on the site web of SEFRAM. . You have to modify frequencies, following the previous paragraph and using the file updated monthly on the web site of SEFRAM.
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– 7848 – If the appliance is not synchronized on all four transponders, the quality indication is red. If the appliance is synchronized on all four transponders but the reception quality is aver- age, the quality indication is orange. Good reception quality (> 50%) → green smiley.
– 7848 – Checking the aligned satellite To check if you have aimed the right satellite, press the NIT key. The appliance searches the MPEG NIT table on one of the 4 transponders and displays the name of the satellite: Attention: The displayed name depends on the content of the MPEG NIT table.
– 7848 – Elevation Tilt angle under which the beam from the satellite reaches your antenna. Measured in degrees using what is specified on the stand of the satellite dish. Polarization Rotation required for the LNB from a vertical line. Measured in degrees.
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– 7848 – The table allows the selection of: LNB bands LNB polarizations. The goal is to make researches shorter again Pressing “START” to launch the search. Pressing “Stop” will abort the research The appliance enters automatically the function Measures when the search is ended or when the user stopped the search.
– 7848 – 6.3.1 Autolock function This function is design to lock on a digital signal (terrestrial, cable or satellite) You just have to enter the frequency or the channel (for terrestrial), then press AutoLock, The instrument will find automatically in few seconds the digital standard, the modulation type and all other parameters of the signal.
– 7848 – 6.4.1 Creation or modification of setups in the library To create or modify a setup in the library, you have to choose a line in the table. A window appears: Attention: If the line contains a setup, it will be erased. To cancel, press: You may erase the setup from the list by pressing the check to the left of the setup or to the setups you have to delete.
– 7848 – 7 TERRESTRIAL mode When terrestrial mode is selected, HOME page of terrestrial mode appears: We will see in the chapter different available menus you can access from HOME page. Remote supply is allowed pushing key : After, you can choose voltage level of remote supply :...
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Enter 4 frequencies of the transmitter you want to check. You can find many different French transmitters in an Excel file available on the website of SEFRAM (download section, then database transmitters TNT) or by clicking under the following link:...
– 7848 – Slowly orientate the antenna until hearing the locking melody and getting the best quality No found transponder → red smiley Average reception quality (< 50%) → orange smiley Good reception quality (> 50%) → green smiley Press...
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– 7848 – A green check shows that the parameter is included in the research. If there is no green check, the parameter will not be taken into account for the research. Attention: The more you select options, the longer is the research.
– 7848 – Any detected channel will be automatically registered at the end of registered setups: New found channels are added one by one into the first available setups of the library, starting from the end of the table Measures – TV – Spectrum:...
– 7848 – 7.3.1 AutoLock function This function is design to lock on a digital signal (terrestrial, cable or satellite) You just have to enter the frequency or the channel (for terrestrial), then press AutoLock, The instrument will find automatically in few seconds the digital standard, the modulation type and all other parameters of the signal.
– 7848 – Creation or modification of setups in the library To create or modify a setup in the library, you have to choose a line in the table, a window appears: You may erase the setup from the list by pressing the check to the left of the setup or to the setups you have to delete.
– 7848 – Echo / Guard interval: Available only for DVBT/H or DVB-T2 standards. Pressing allows you to access to Echo Guard interval measurement. Signal without echo Signal with echoes and pre- echoes Pressing changes the horizontal scale (distance). Horizontal scale can be set in µs, km or miles by pressing...
– 7848 – The broadcasting norms DVB-T and DVB-T2 define a modulation parameter called "guard interval" where echoes won't disturb the reception. The transmission of digital data (Symbol) is interrupted during the guard interval. A delayed (or advanced) symbol of any shorter duration than the guard interval will not disturb the reception.
– 7848 – 8 Measures Setup modifications The various parameters are: The name of the setup The frequency of the emitter or transponder (and the true frequency of satellite) The standard and bandwidth for DVB-T/H and DVB-T2 ...
– 7848 – Example in TNT : Signal level Signal/noise ratio of the signal The appliance makes different measurements according to the current standard. The other possible measurements are: Average measurement Peak measurement Power measurement. The best is to be the closest possible of the green bar without exceeding it.
– 7848 – Terrestrial band The appliance automatically makes level measurements on the Video carrier wave. The following table sums up the measurement types and the frequencies of the audio carrier waves for each standard: Standard Video carrier Measure Sound carrier...
– 7848 – Seuil min Seuil max Digital measurements In digital measurement mode, in addition to the RF level and to the C/N here above, the appliance also dis- plays the various BER (Bit Error Rate), the PER (Packet Error Rate) and the MER (Modulation Error Ratio) under DVB-T/T2, DVB-S/S2 or DSS.
– 7848 – DVB-S2 DECODAGE DEMODULATEUR LDPC TUNER MPEG BERo BERi Display of the measures of: BERi : error rate before LDPC BERo : error rate after LDPC PER : error rate after BCH (lost packets) ...
– 7848 – 9 Spectrum analyser Pressing SPECTRUM gives access to the SPECTRUM ANALYSER function. (graphical representation frequency / amplitude of the present signals in the input of the device) Satellite Terrestrial To swap from between satellite and terrestrial, go to Home page and press...
– 7848 – 10 Image and Sound Pressing the TV zone gives access to the TV function. 10.1 Digital TV The name of the service and its main characteristics are displayed on top left of the screen. 720x576i: picture resolution 720 pixels / line, 576 lines, interlace ...
– 7848 – 10.3 Audio To set the volume, press an adjustment bar shows up: The instrument can decode the following digital sound formats: MPEG-1 L1/L2 Advanced Audio Coding License Via Licensing HE-AAC High Efficiency AAC License Via Licensing ®...
– 7848 – 11 LNB – DiSEqC (Satellite mode) This page allows or not the activation of the remote power supply. In this page, there is the possibility to use normal mode or expert mode. Expert mode allows to carry out a larger number of parameters.
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– 7848 – Configuration line in normal mode: - LO1 and LO2 Frequency: LO frequencies low and high band of LNB - LO selection: band commutation on the LNB (22kHz, ToneBurst or DiSEqC) - Polar selection: polarization commutation on the LNB (13/18V...
– 7848 – Switch line Uncommitted line Satellite Position Commande DiSEqC Position Commande DiSEqC Pos A Option A + Position A Pos 1 Input 1 Pos B Option A + Position B Pos 1 Input 1 Pos C Option B + Position A...
– 7848 – 11.1.3 DCSS (satellite remote power supply in expert mode) Description: DCSS Digital Channel Stacking system: signal distribution system using frequency transposition. Used in satellite distribution for multiple or single dwelling, with several set top boxes. To give several receptors access to the whole spectrum and all polarizations, you need one coaxial cable per receptor and a suitable installation (multiple LNB, Quattro and multi-switches).
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– 7848 – The DCSS mode has priority on all other modes: selection polarization, selection OL, switches committed and uncommitted and positionner. 2 Modes : SATCR : Satellite Channel Router, standard EN50494 (or SCD, Unicable, …) Distribution of the satellite signal with only one coaxial cable to 2, 4 or 8 different receptors.
– 7848 – 12 Configuration For configuration, go Home page of terrestrial mode or satellite mode, then press configuration 12.1 Language You can select your language by pressing the « flag » (below). Press the flag corresponding to your language:...
– 7848 – 12.2 Frequency map This key allows you to select the terrestrial frequency map of the appliance: 12.2.1 Update See chapter Software update for more details. 12.3 Factory recovery A complete set-up of the appliance under its FACTORY configuration, with confirmation...
You can make a backup on a USB stick of your setups of your appliance by pushing « « Configuration Ex- port ». And you can import from a USB stick this configuration with the touch “Configuration import”. You can also update checksat configuration available on SEFRAM’s website: http://www.sefram.com/Maj_soft/Sat.csv...
The update requires an USB stick. To achieve the update: - Download the update file 784X_VX.X fichier zip on our website (www.sefram.fr) - Insert a USB stick on your PC - Unzip the file onto the root of the memory stick...
– 7848 – 14 Connection of the appliance to a PC The appliance has ETHERNET interface that make it possible to connect directly to a PC. For this type of connection, no driver is necessary. Connect your appliance to your PC by using a crossed ETHERNET cable (available in option with the num- ber 298504246 asking SEFRAM).
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– 7848 – Attention: If the PC has already been connected to Ethernet (network, modem…), it is necessary to reboot the PC before connecting your appliance. For the Ethernet connection of your appliance to a computer network, see the following scheme:...
– 7848 – 15 Displayed messages The appliance may display messages while working. 15.1 Alert messages Low battery: the appliance is about to shut off in a few minutes. Confirmation request for an important action. Remote power supply issue: cable under tension or excess intensity above maximum.
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– 7848 – Messages of the same king may show up; the pop up window is an alert; the corresponding message ex- plains the issue.
CONNECTIONS Erroneous measures At any measurement This "advice" does not engage the responsibility of SEFRAM I.S. It guarantees the best possible use of the characteristics and the preservation of the product. Routine maintenance: The basic maintenance is simply cleaning the outside of the appliance. Any other operation requires a trained personal.
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100% good functioning pixels in the display zone. They specify a number of possible de- fective pixels at the surface of the screen. The SEFRAM quality service has preconditioned the mounting of the screen on your instrument to the re- spect of the acceptance conditions of the manufacturers.
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