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If the video seems to zip off the screen as soon as you stop on the channel try

changing the receiver’s polarization format. That is, if you have your odd

channels set for vertical polarization and your events for horizontal, change the

format to odds-horizontal, evens-vertical. You may not even know the present

polarization format changes the relationship of the feedhorn’s pick-up probe by

90 degrees. If changing the format keeps the video on the screen, then it has

to be the correct setting for that satellite on your system.

Select the best skew setting for the odd and even channels. The skew is the

fine tuning of the feedhorn’s polarization, required because the satellite’s

signal polarization is only truly “horizontal” or “vertical” when the satellite is

positioned at the same longitude as the installation site. The skew and format

buttons are found either on the front of the receiver or on the remote control.

Many receivers with on-screen graphics require you to choose these functions

on the menu.

Most receivers have a LED signal level indicator on the front panel or a digital

level indicator presented by on-screen graphics. The level indicator provides a

better reading of peak satellite performance in contrast to just viewing the

picture on the TV screen.

4) For locating satellite in the lower section of the Clarke Orbit, push the dish

right and left on the pole and move the drive east and west in slight

increments until you are satisfied you have the strongest signal. Then

tighten the mount’s bolt onto the pole so that the dish won’t rotate. Do not

tighten them down firmly yet, however. Note the numerical reading provided

on the receiver’s front panel or on-screen display that corresponds to dish

position at this location. This is a relative number that changes as the dish

moves.

5) Move the dish east or west until you reach the zenith for your location.

Select an active transponder for the satellite closest to the east or west of

arc zenith or turn the scan control on. Now move the dish in the direction of

the nearest satellite. If all the settings have been done right you should not

have a problem finding it.

6) For locating satellites that are in the upper section of the Clarke Orbit, jog

the actuator drive east and west and adjust the elevation bracket up and

down slightly. You should not have to move the elevation setting very much

because you already have pre-set it for your location. The rule of thumb

here is : 

Rotate the dish on the pole and use the actuator to receive lower

satellites, but do not rotate the dish on the pole to receive upper satellites.

Adjust the elevation of the dish and use the actuator to receive upper

Summary of Contents for Large Dish

Page 1: ...off and the dish flung through the sky Because roof top installations are more susceptible to microwave interference than those on the ground a site survey with a spectrum analyzer or an on site rooftop demonstration with a small potable dish is an absolute necessity in any country where microwave interference is a major potential problem If several of your neighbors have antennas you can check wi...

Page 2: ...hich is curved so that it resembles a hook allows the feed to be mounted looking back at the center of the dish Guy wire kits are available for button hook supports that will provide the additional stability required for reception of both C and Ku band signals Ku band signals are much higher in frequency and there fore are beamed Earthward in much smaller wave lengths Consequently the antenna curv...

Page 3: ...ntenna s rim so that it crosses in the center of the dish The depth will be the distance from the antenna s center to the string Many feeds today have adjustable scalar rings These feeds can be broken down into two parts a round flat scalar plate with concentric circles on its surface and the wave guide onto which the LNB is mounted This wave guide fits into the center of the scalar plate and can ...

Page 4: ...iewing TV signals and watching the receiver s signal level indicator If you are going to have a technician during the final stages of the installation he will have a portable meter to use at the dish Two people also can talk back and forth via walkie talkie or portable phone while one makes adjustments to the dish and the other keeps an eye on the quality of the reception Direct burial satellite c...

Page 5: ...c impedance rating of 50 ohms and is not suitable for satellite TV use Be sure that the cable you buy is 75 ohm coax There are several different kinds of 75 ohm coaxial cable available RG 59U coax can be used to span distances of up to 100 feet For longer lengths lower loss RG 6 or RG 11 are used Direct burial satellite cable contains one or two spans of RG 6 Since RG 6 is slightly larger in diame...

Page 6: ...e and black for ground A stranded wire is used because it is more flexible and won t break as easily as a solid wire The shield an aluminum foil wrapped around all three wires keeps impulse noises from entering the line and giving false pulses to the receiver The receiver uses pulse to keep track of the position of the feedhorn s pick up probe You therefore can adjust or skew the position of the p...

Page 7: ...minals Some satellite receivers have an external power supply that puts the large transformer outside of the receiver chassis This reduces the receiver s size as well as its operating temperature The power supply is actually a large transformer that turns 110 or 220 volts a c into 24 to 36 volts d c to power the actuator s d c motor Grounding The System If your home s a c electrical ground is clos...

Page 8: ...omewhere in the middle of the continent observe how they are mounted on existing systems in your area or ask your satellite retailer which is the correct method for you Dish Alignment Settings You have now completed the basic construction of the dish and are eagerly anticipating your first pictures from space To fine tune those pictures and get your dish to track you or someone you can communicate...

Page 9: ...ast satellite to the east and west Setting the polar axis elevation of the dish Extend the drive until the dish is looking at the highest point in the sky Set the inclinometer onto the polar axis of the mount to the correct elevation angle for your location Setting the declination Declination is the offset angle between the polar axis of the mount and the rim of the dish which permits the antenna ...

Page 10: ...en as you move the dish past a satellite You can go back to where the flashed occurred turn off the scan feature and identify the satellite by comparing the programming you encounter to the satellite TV program grids Some satellites only carry a few active transponders Without the scan feature you would need to select an active transponder and tune to the correct polarization before you could find...

Page 11: ...just viewing the picture on the TV screen 4 For locating satellite in the lower section of the Clarke Orbit push the dish right and left on the pole and move the drive east and west in slight increments until you are satisfied you have the strongest signal Then tighten the mount s bolt onto the pole so that the dish won t rotate Do not tighten them down firmly yet however Note the numerical readin...

Page 12: ...tomatically appear on their respective channels on the TV If your satellite receiver does not have this feature you will need to purchase an A B switch from your local satellite or electronics store Both the satellite receiver and local antenna connect to the A and B input ports on this switch while the single output port connects to the antenna input on the TV This switch will have to be changed ...

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