Philips TW0200 Manuale Utente

Chapter 7

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7-2 MICROWAVE SYSTEM A/T Microwave A/T comprises of - Local A/T of all stations, and Repeaters.

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3. Test on receiver:- - Check of RLO frequency :- Check of RLO frequency with unritsu or HP frequency counter, measure frequency and offset - Wri

7-2.2 VSWR: - Voltage standing wave ratio Standing wave :- If the impedance of the load (Antenna) and source ( Generator ) is not equal, that is n

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MSA Transmitter Fig. 7-10 Conversion chart of VSWR, Retur

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Please see the Wiltron diagram, Anritsu detector converts power into voltages. - Connect Open , select - Connect Short , select - Connect device

182 . Check of BER with IF Loop: - oop IF Trans to If Receive and test 140 Mb/ STM-1 on DTA set for 0 PPM and ± 15 PPM. The result should be 0.

7-2.4 HOP A/T OF 11 GHz 140 Mbps or STM-1 1] Receive level: - Note down Surveyed level, Nominal level and measure Rx RF level at Rx IN by power met

4] BER measurement:- - Ask distant station loop on 140 Mb or STM-1 which is installed. - Carry out BER Test as usual for 0 and ± 15/20 PPM.

which transmits and receives Radio signals agnetic waves. Antenna used for the transmission of Radio, TV, , GSM and CDMA network. y in all directio

7-3.2 3. Link Budget:- Link budget is to calcula Receive level taking into consideration all gains and losses in the ne rk. It accounts attenuat

7-3.3 5. Fresnel zone: - No. of concentric ellipsoid revolutions which defines volumes in radiation pattern of ircular aperture and it is due to

-3.4 8. Rain attenuation: - As the water droplets scatters and absorbs radiation the effect of es on increasing with the increase of frequencies

Antenna diversity: - In this diversity schem microwave signals are transmitted along st instantaneously on failure of 11 Thifor ove1. B2. Frame Sync

13. Wayside dropping: - If any small station in any hop requires 2 MB stream, an additional card is provided in system so as to handle the traffic of

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7-4 2 GHz / 8 MB D/ UHF System A/T Make: - ARM-2208-M3 Specification: - 7-4.1 - Frequency band 2.0 to 2.3 GHz. range 45 dBm for thresho

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- Disconnect RF cable from Rx In. - Make a test set up as above for AGC calibration. - Select RF frequency and level say -40 dBm

7-4.4 HOP/ through A/T 1. Receive level: - - Measure RF Rx level at Rx IN and compare it with surveyed level. Deviat- ion between surveyed and me

- Tele command status TC1, TC2 OFF. - supervisory card out. - ous alarm on Transmitter. - / front panel synthesizer goes 0/0 lock. ecove

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7-1.5 Meters for M/W System 1. Power Meter Anritsu - ML 4803 A 2. Power Meter HP - 437 B, 4368, Philips 3350 3. Spectrum Anal

7-1.6 Before proceeding any M/W system A/T --------- 1] Get TT-O, TT-1 duly filled in all respect, 2] Collect Survey report which includes,