The simple maintenance of the earth station antenna can reduce the antenna failure probability and extend the antenna life, so regular and complete antenna maintenance planning will be helpful for the antenna's normal operation.
Appropriate maintenance planning is a kind of commercial insurance. Check the completion of the whole structure and ensure the normal operational capability by the simple and low-cost surface maintenance; Check the electrical performance, and comply with the maintenance regulation in the manufacturer’s operational maintenance manual so as to reduce the occurrence of antenna failure.
1. Surface Maintenance
Check the complete paint surface and electroplating surface, as well as the fixed structure. First, rub the rust spot on the electroplating surface with a metal wire brush or abrasive paper, and then coat a layer of zinc-rich coating or a layer of rust inhibitor that won’t require the complete clearance of the rust.
The user should repair it even if only a little of the finish peeling, spalling, or color fading, or it will become more and more serious. And the user must accord with the antenna manufacturer’s regulation for the paint surface and coating specification because the wrong coating method will affect the signals accept. For example, the dark-colored antenna reflector surfaces can absorb easily, so it can give rise to high temperatures, which can cause signal distortion. Too much lead paint can make the signals lost by attenuation or scattering.
2. Antenna Fasteners
The nuts, bolts, rivets, and other fasteners in the installation will be affected by atmospheric effects or internal corrosion. Regardless of any corrosive components and the error installation will be found in the routine maintenance. At this time the users should tighten the loosened nuts and replace the lost, rust, and corrosive components.
With the ASTM (American Society for Testing and Materials Institute) A325 or other occasions of friction components, the user must replace the loosen or corrosive components, because in the process of re-tightening it will make the fasteners get the reuse term. Also, the corrosive A325 metal parts should be replaced not tightened.
Often there’re pins inserted in the pivots of the adjustable antenna bracket. Check if the activities of these jointing are flexible, and lubricate the oil with a grease-gun with an oil jet. If the antenna rotates not flexibly, the user should replace the pin.
Check the metal fasteners on the antenna reflector and back structure. Except ASTM A325 must be replaced, the user can tighten the loosened parts. The lost, rust, and corrosive fasteners should be replaced. These check processes are also suitable for the operational platform when assembling the antenna, as well as assisting the reflector and reflector support.
3. Ground
No matter how high the buildings, the antenna, and bracket should be grounded to prevent lightning strikes. Inspect if the mechanical grounding system and non-mechanical connection are connected.
Analyze if the grounding connection is connected by the earth loop impedance instrument. According to the test results, the user can decide the cost of the excavating work. Check if the mechanical grounding parts are rust, corrosive, or loosened. Replace the rust and corrosive fasteners so as to limit the inductance value.
Unload the grounding sharp dogleg head on the antenna or bracket. In contrast to the Biddle megohmmeter, test the target value which is made after site grounding resistance to check the grounding system. According to the test results determine whether adopt auxiliary grounding measures.
On the place which can use the step auto-tracking device, check whether the pedal is level by a longitude and latitude stadia. If the pedal is not level, it can affect the antenna position calculation. Adjust the level nut under the base plate to make the antenna keep level.
If the anchor bolts prevent adjusting the pedal level, adjust it while fixing the antenna. After adjusting, check if the cement sealing of the antenna foundation and anchor bolts spall, crush, and shift. If it is damaged, even a little, also should be repaired. After adjusting, the controller should be programmed again.
If some devices are mounted in the antenna box which is on the back of the reflector, check if there’s accumulated water or a large number of termites or rodent-infested in the box. Repair or seal the crack, even if it is little. If the user doesn’t care about it, ants, mice, and other animals will cause incredible losses.
4. Cable and Connector
The intermediate facility link cable transmits the signal between the antenna and the computer room. Check if these cables are damaged. If there’s something wrong with VSWR or insertion loss, the user should test and check whether the cables need to be replaced or repaired.
When repairing the cables, the user can splice them in the new position, but it can cause some signals attenuation. With s Time Domain Reflector (TDR) check the position of the broken line. With a voltage, meter check all the cables and connectors of the electrical properties and connectivity.
The coaxial cable with a bent head in excess of the minimum bend radius should be tested. After testing if it doesn’t comply with the cable specification, it should be replaced.
Ensure the IFL cable and other cable support and routing (positioning and bending radius) accord with the manufacturer’s technical requirements. Replace the lost, rust, and corrosive backup supports. When supporting IFL cables, it is better to use stainless steel cable link or cable clamp than a plastic rope. Stainless steel link should be used to fix the elliptical waveguide. Inspect the cable manufacturer’s recommendations.
If the stainless steel link or clip is not useful, and the cable manufacturer hasn’t specified any stainless steel link or clip, in this case, the user can only use black nylon rope, the white or bright-colored rope is easy to be fragile in the sun. The user should always check the cable rope because the nylon rope is easy to be loosen than the stainless steel clip.
Check the IFL connectors and connection parts. Replace the connectors which appear to fracture line, line antihypertensive, or other problems. If IFL cables come from the catheter, the user should check the catheter and other connectors. Check if the catheter input is strict, if there’s accumulated water in the catheter, the water will freeze, which will squeeze the cable broken.
Check the feed combiner flexible elliptic waveguide line, if it is damaged, replace it. If the system inflation pressure is not enough, corrosion can change the signal-to-noise ratio to affect the signal or cause the antenna to stop working.
5. Shutdown Maintenance
Some maintenance work should be done when the antenna doesn’t stop working, but most of the maintenance work needs to be done after the antenna stop working. For example, when moving the antenna or cutting down the IFL line, the user must shut down the antenna. First, check the antenna azimuth and elevation bracket. Look if there’s some fracture and hardening phenomenon for the protection cover of the support bracket, if needed, replace it.
For the motorized antenna or the antenna which points to a Satellite for a long time, sometimes those antennas also need to be moved. This step can be considered as part work of the daily check-in each year, except Antesky Science Technology Inc Have another regulation. When doing the maintenance, according to the maintenance period table of Antesky Science Technology Inc (Antenna Manufacturer: clear the support screw, and lubricate the oil.
If the user finds the support bar moved on one position and was worn, it should be adjusted. When rotating the antenna, ensure that the mechanical limit switch can stop after the antenna motor finishes the planned journey. The limit switch malfunction can make the antenna rotate continuously until it will be damaged or hit by other objects.
Check the operational maintenance of Antesky Science Technology Inc note the special requirements and suggest when to lubricate the oil or when to inject the oil for the azimuth, elevation, polarization, and other motors. The antenna motor wire box should be dust-free and moisture-proof and all the connections should be fixed. If due to improper maintenance of the equipment, Antesky will not be responsible for the warranty.
6. Maintenance Record
Keep a maintenance record. At the beginning of installing the antenna, leave a record with the date and photos. Then maintain once, keep a record once, so as to keep a complete antenna system record.
In the antenna valid life keep a record of antenna pattern so as to find the phenomenon of the system signal dropping.
If it is required to shut down the antenna and do the maintenance, you’d better arrange the maintenance work when the antenna doesn’t work or within one hour during the off-peak period. If the antenna can’t stop working, transfer this antenna’s work to another temporary earth station antenna.
Conclusion
Preventive maintenance of Earth satellite dishes incurs costs. However, this cost is virtually non-existent when compared to unexpected and potentially prolonged downtime, scrap parts and other hassles that hinder efficiency.
By getting into the habit of performing regular maintenance inspections, you can keep your earth antenna satellites working stably and efficiently