MT-MR PLATINUM. POINT TO POINT AURAL RADIO RELAY SYSTEM
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the conclussion is that they are some facts or factors about the path, the terrain, or the antennas, that are not well
calculated, because these calculations performs in a quite effective fashion.
24.- Once Transmitter and Receiver antennas are properly oriented, de-energize transmitter. Disconnect receiving
antenna from receiver and connect the input of a Spectrum Analyzer to the antenna system, via the corresponding
adapter cable. Watch for any interference in the selected or adjacent frequency channels, verifying that is no
possibility of interference over the transmitted RF signal. If there is some spurious signal occupying the assigned
channel, proceed to make a photo of the analyzer's screen and go to the government correspondent authorities to
investigate and detect the spurious signal, or to perform a change of assigned frequency.
25.- Keeping the Spectrum Analyzer connected to antenna system at receiver end, energize transmitter again, and
check the presence of spurious signals and harmonics incoming from the link transmitter additionally to the main
received signal, measuring, if any, the amplitude of such spurious signals. Report the appearing of such signals
directly to OMB Laboratories for making the necessary corrections. Perform such measurement with an instrument
able to reach the 2 GHz frequency band.
26.- If there is no harmonic or spurious troubles, disconnect Spectrum Analyzer from receiving antenna and connect
the antenna to the receiver input, restoring the system to normal service condition. If abnormal conditions such as
frequent fadings are observed during the exploitation period of this system, please contact OMB Laboratories in
order to perform a more detailed analysis including a recording of the receiver's AGC during the most critical
months of the year, etc.
5.2.- Operation and Maintenance:
MT-M
R
Platinum system is quite easy to operate, since it is manufactured for use in unattended repeater stations.
Its monitoring capabilities enables it to be throughly checked without any difficulty. About its maintenance, the most
critical point to be checked periodically is the cooling axial blowers, who should be replaced each three or four
years of continuous work, independent of its operating condition ( It’s life time is about five years). General
frequency response and distortion measurements should be run each six months, to guarantee that system is in
perfect operational condition. Inspection of received signal strength should be carried monthly, to assure that both
antenna systems are in good condition. Transmitter's power output should also be checked monthly, and system
frequency check should be performed each six months, taking three readings, morning, noon and night and making
the average of frequency drift, if any.
Both equipments should be kept clean and free of dust, dirtiness, moisture and any external agressive agents,
such as contaminated environments or so. Remember the temperature specifications of this system and do not
attempt to violate these conditions.
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