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Rainy season Preparedness 2009. Rain Fade. Rain, snow or even rain-filled clouds passing overhead can reduce the intensity of the incoming signals. This results in FREEZING or NO PICTURE. Torrential downpours can lower the level of the incoming Ku-band satellite
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Rain Fade • Rain, snow or even rain-filled clouds passing overhead can reduce the intensity • of the incoming signals. This results in FREEZING or NO PICTURE. • Torrential downpours can lower the level of the incoming Ku-band satellite • signal significantly; this may severely degrade the quality of the signals or even • interrupt reception entirely. • As in the rainfall or rain filled clouds, the quality of the signal starts decreasing. • If the tracking is not at peak, the signal will be lost immediately. • Maximum peak tracking will reduce the time duration of “NO SIGNAL” during rainfall.
Rain Fade -To Counter Act... To Counteract • Track the antenna to peak level with Signal Strength (intensity) & Signal Quality • (BER,MER) & Skew to maximum level. Effect of Noise on Digital Systems (Gradually Poorer Quality / MER) 7.0 dB MER 50% Quality 9 dB MER 70% Quality 6 dB MER 25% Quality 14 dB MER 99% Quality No change No Signal Freezing The picture remains same from 14 dB MER to 9 dB MER. It starts freezing at 7 dB MER & at 6 dB MER there is No Signal. This shows that the tracking has to be done till peak MER / Signal Quality is achieved for a particular dish antenna.
Objective • At the end of this session we will understand the ---------- • Importance of Signal Strength. • Importance of Signal Quality/MER/BER. • Importance of SKEW. • Safety points.
Important Points for Installations • Track the Dish Antenna with maximum Signal Strength (intensity) & Signal Quality • (MER/BER). • Do SKEW with utmost care to achieve maximum signal quality (MER/BER) for all • the transponders. • Confirm the readings of all the transponders to peak. • All the Bolts, Screws, Nuts should be tightened to maximum level. Over tightening • should be avoided. • Follow the Look Angle Chart for all the three angles- Azimuth Angle, Elevation • Angle (Inclination Angle) & Polarization (Skew) for the particular area. • Prefer wall mounting for maximum installations & check the wall thickness before • installations. • Mast should be always in 90° wrt horizontal plane (Ground). • Check the peak tracking by pressing all four sides of reflector one after one & see that the • readings should not increase. It should decrease when pressed.
Important Points for Installations • Put all the necessary loops to the cables where ever required to avoid water • ingress in the STB. Sharp edges to be prevented with double sided tapes fixed to • the cable. Avoid cable routing through damp areas. • Use Sealant at all the through holes in the wall to stop water ingress, cable cuts, insects • immigrations etc. • Sat meter should be full charged before any installations. • All F-connectors should be fixed as per our norms only as it may result in no video • for some channels. As we are working on extreme high frequency so • connectorization has to be done very precisely. • Cable ties, P-clips to be properly fixed to the cables. No over tightening of the cable • ties & P-clips to be done on the cable. • Proper ventilation for STB to be checked before installing it.
Universal Single LNBF X-Power Single Universal LNBF MTI (Reliance) Single Universal LNBF Sharp Single Universal LNBF MTI (Reliance) Single Universal LNBF
Skew Angle Setting-Sharp Universal Single LNBF • The LNBF (Universal Sharp make) has markings on the top. • There are, say 9 divisions on each side with a centre point marking in the middle of the LNBF. • Each division corresponds to 5 degrees measurement • The divisions has to be adjusted according to the polarization given. • For eg. Mumbai’s Polarization is - 43.00 deg, so we have to set at 8.2(approx) division of the LNBF with • the centre point of the LNBF Clamp. Centre Point of LNBF LNBF CLAMP Centre Point of LNBF Clamp -43 degree for Mumbai
Skew Angle Setting-MTI Universal Single LNBF • The LNBF (Universal MTI-Reliance make) has markings on the top. • There are say, 5 divisions on each side with a centre point marking in the middle of the LNBF. • Each division corresponds to 5 degrees measurement • The divisions has to be adjusted according to the polarization given. • For eg. Mumbai’s Polarization is - 43.00 deg, so we have to set at 8.2(approx) division of the LNBF • with the centre point of the LNBF Clamp. Centre Point of LNBF LNBF CLAMP -43 degree for Mumbai Centre Point of LNBF Clamp
Skew Angle Setting-MTI Universal Single LNBF • The LNBF (Universal MTI-Reliance make) has markings on the top. • There are say, 5 divisions on each side with a centre point marking in the middle of the LNBF. • Each division corresponds to 5 degrees measurement • The divisions has to be adjusted according to the polarization given. • For eg. Mumbai’s Polarization is - 43.00 deg, so we have to set at 8.2(approx) division of the LNBF • with the centre point of the LNBF Clamp. LNBF CLAMP Centre Point of LNBF -43 degree for Mumbai Centre Point of LNBF Clamp
Skew Angle Setting-X Power Universal Single LNBF • The LNBF (Universal X Power make) has markings on the top. • There are say, 8 divisions on each side with a centre point marking in the middle of the LNBF. • Each division corresponds to 5 degrees measurement • The divisions has to be adjusted according to the polarization given. • For eg. Mumbai’s Polarization is - 43.00 deg, so we have to set at 8.2(approx) division of the LNBF • with the centre point of the LNBF Clamp. Centre Point of LNBF LNBF CLAMP Centre Point (Ref) of LNBF Clamp -43 degree for Mumbai
Importance of Skew • SKEW is the MOST important adjustment for tracking in BIG TV. • As we are using two polarities (Vertical & Horizontal), so SKEW has to be done very • precisely. • Track the satellite (MEASAT-3) with Transponder 16(12523MHz, Vertical high) in the • beginning with maximum signal strength & signal quality (MER/BER). • Next move to Transponder 22 (12683MHz, Horizontal high) & track to maximum • signal strength & signal quality (MER/BER). • In both the situation the SKEW should be done precisely. • While we adjust TP22 to maximum Quality (MER/BER) by Skewing, we need to go • back to TP16 once again & check the Quality (MER/BER). In this situation we will • get a low signal Quality (MER/BER) on TP16 than what we have tracked initially. • Now again we have to adjust the SKEW to such an extent where we will receive a • maximum signal quality (MER/BER) for both TP16 & TP22.
Importance of Skew • For Eg. Initial SKEW of TP 16, MER=14dB • Initial SKEW of TP 22, MER=13.2dB (Here in TP 16 MER goes to 13dB) • Final SKEW of TP 16, MER=13.8dB • Final SKEW of TP 22, MER =12.9dB • Check all the transponders readings for maximum signal strength (intensity) & signal • quality (MER/BER).
Safety Points • General safety rules to be followed through out the installation. • Do not Install during rainfall. • Do not climb on the slope or slippery locations during rainy season. • Do not work near the electrical open wires on the roof top or any other such location. • Do not expose the Sat meter or Sat Hunter to rain. • Do not do any risky installations where service feasibility is absent. • Ensure insurance for all installers & assistants. • Do not drill in the rain. • Take utmost care inside the customer’s house during installation.
Safety Points • Drive two wheeler with extreme precautions & use helmet for both installer & asst. • Do not throw any equipments or tools. • Switchoff all the equipments when not in use. • Keep all tools & equipments away from customer’s reach. • Always use ok tools & equipments for installations. • Do not keep any tools or equipments or mobile on the top pocket during installations.
Purpose • To overcome the SRs, related to Rain fade, following counter actions to be implemented • in the field immediately. • Health Checkup by Service Executive / MDU Executive for those ISPs having high • volume of SRs of No Signal, Dish Misaligned, Installer’s problem. • Live Health Checkup by Service executive / MDU Executive / ISP Owner or • Supervisor for installations. • ISP owner / Supervisor will do Health Checkup for the installations. • CC to be aware for Rain fade & No Signal problem due to it.
Process • New Installations: • Whenever there is a new Installation at any location, the installers need to follow all the • necessary steps for peak tracking mentioned in this module. • Existing Installations: • For any Installations & SRs, Installers need to do a compulsory Health Checkup of other • existing installations at that particular locations. • Whenever there is a SR at any location, the installers need to do a compulsory Health • check up of existing installations for maximum customers near by to that location. • As ISP is now into RCV process also, the Installers has to do a compulsory Health check • up for the particular customer where the RCV is delivered. • Regional Service Heads to ensure for those ISPs having high volume of SRs of No • Signal, Dish Misaligned, Installer’s problem & do 100% health checkups for their • installations. RSH also should ensure the complete installation data with their respective ISPs. • Installers need to carry the Audit Format to attend the SR/ Health check up & capture all • the details. • NOTE: This health checkup will help to reduce the future increase of SRs in Rainy season thus saving the cost.
Check List • The Teams need to check for the below instructions before moving to the field for audit. • Complete tool kit with all tools in working condition. • Sat meter (Max peak or Rover with full charged) is compulsory for checking the signal. • Sealant, P clips, Cable ties should be always with the teams. • RCV to be carried for all health check ups. • Blank audit formats to be present with the teams. • Teams should carry the look angle chart with them. • Mobile phones to be charged.