Subreflector Adjustment

Survival Struts

After the satellite has been acquired and testing has taken place with the spectrum analyzer, the subreflector may need to be adjusted to maximize optimum performance of your anten- na. The following procedures should be followed if a subreflector adjustment is required to maximize optimum performance.

NOTE: All INTELSAT Type Approved antennas do not require subreflector adjustment.

Before proceeding, azimuth and elevation patterns should be conducted to determine the adjustments that need to be made. The goal is to achieve a high peak on the main lobe and even distances between the main lobe and sidelobes as shown in Figure 4-6.

NOTE: No adjustments should be made in the receive band.

If your pattern dictates a need to adjust the azimuth angle(the left sidelobe requires adjust- ment), the west side of the subreflector should be adjusted outward by loosening the screws on the subreflector and adjusting the left side outward. An easy way to remember this adjust- ment feature is through the acronym WOLD (West Out Left Down).

If your pattern dictates a need to adjust the elevation angle(the right sidelobe requires adjust- ment), the bottom side of the subreflector should be adjusted downward by loosening the screws between the subreflector and the struts and adjusting the bottom side of the subre- flector downward. An easy way to remember this adjustment is through the acronym BOLD (Bold Out Left Down).

Each of these adjustments should be repeated until each sidelobe is of equal distance from the peak of the mainlobe.

After the BOLD and WOLD adjustments have been made, it may be necessary to adjust the main lobe. The goal is to achieve a high null depth (distance between lower intersection of sidelobes and top of main lobe) as shown in Figure 4-6.

In order to adjust the main lobe pattern characteristics ALL subreflector adjustment screws should be adjusted at the same degree (Note: Because the azimuth and elevation adjust- ments have been set, it is very important that the null depth adjustment be carefully conduct- ed. Be careful not to alter any previous adjustments that have been made to the subreflector. Follow the procedure listed below when adjusting the null depth of the main lobe.

C-band feeds - Adjustment screws are 3/4 X 10. Move 1 turn per 1dB of imbalance.

Ku-band feeds - Adjustment screws are 1/4 X 20. Move 1 turn per 1 dB of imbalance.

All adjustments should be continued until the desired pattern is achieved. Upon completion the antenna should be properly aligned with the satellite for maximum performance.

The survival struts are used when winds are expected to exceed 125 mph (200 kph). The antenna should be moved to 90 deg. (zenith) elevation.

Undo the adjusment nuts holding each strut to the enclosure. Swing each strut down into the adjoining slot in the turning head. Tighten the nuts to the turning head block. Torque the nuts to the full effort of one man using a three-foot wrench.

NOTE:

Do not attempt to operate the azimuth jack while the survival struts are deployed.

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Operation

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Andrew ES76PK-1 installation instructions Subreflector Adjustment Survival Struts
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ES76PK-1 specifications

The Andrew ES76PK-1 is a robust and highly efficient satellite communication antenna designed for both commercial and military applications. Its innovative design and advanced features make it an exceptional choice for high-performance connectivity.

One of the standout characteristics of the ES76PK-1 is its impressive gain. With a gain of approximately 76 dBi across a wide range of frequencies, it ensures optimal signal reception and transmission even in challenging environments. This high gain makes it ideal for applications requiring reliable long-distance communication, such as remote site operations or disaster recovery efforts.

The construction of the ES76PK-1 also prioritizes durability and resilience. Built with sturdy materials, this antenna is resistant to harsh weather conditions, including high winds, rain, and extreme temperatures. Its lightweight yet robust design allows for easier installation and maintenance, making it suitable for both fixed and mobile setups.

In terms of technology, the Andrew ES76PK-1 leverages advanced polarization techniques, which enhance its ability to transmit and receive signals effectively. This polarization capability ensures minimal signal degradation and interference, providing users with consistent and high-quality communication links. Furthermore, the antenna supports multiple frequency bands, thus offering flexibility in deployment and compatibility with various satellite systems.

The antenna's design incorporates a high level of precision engineering. This not only contributes to its excellent performance but also allows for fine azimuth and elevation adjustments. This feature is crucial in aligning the antenna accurately with satellite signals, further improving the quality of service for users.

Another key aspect of the Andrew ES76PK-1 is its compatibility with a range of RF systems. This versatility makes it a favored choice among service providers and enterprises looking to implement or upgrade their satellite communication infrastructure.

In summary, the Andrew ES76PK-1 stands out in the competitive landscape of satellite communication technologies. With its high gain, durable construction, advanced polarization, and compatibility with various systems, it meets the stringent demands of modern communication needs. This antenna is an excellent investment for anyone looking to achieve reliable and efficient satellite connectivity.
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