LNB skew, whats required for digital?

satbadger1

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Im new to digital sat having just got rid of my old anologue system. Ive replaced it with a plaza550 and universal 0.3 LNB. I receive loads of tp's but wondering how i should have positioned my LNB. Its vertical on 19 E but angle changes as the dish moves west. Obviously with the anologue the skew could be changed electrically with the poloriser. I dont have a poloriser now so is there an optimum Angle for the LNB or does it not matter with digital?

Grateful for any advice
Cheers
 

2cvbloke

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Just twist the LNB clockwise from centre until you have the best signal quality (that's facing the dish from the front by the way)...
 

steffo78

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it is the same as with analog, the satellites have not changed.
If you want best possible you should use your old polarizer.
Othervise it is more important on weak satellites as usual, on 19E no problems without optimal setting.
If you have a motor, the skew is quite ok for most of satellites.
In that case you can adjust skew at lowest signal satellite.
 
J

Jeff_19341

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Hi satbadger1

For a motorised set up your LNB should be vertical on your South satellite for optimum pick up of the V & H transmissions. The motor will slew your dish round and the face and hence LNB will be true for picking up the V & H from the satellites.
 

2cvbloke

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I bet I've confused you, I didn't notice the moving dish bit.... :-ohmy
 

rolfw

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As the other guys say, the motor should adjust the skew, as the LNB moves with the HtoH mount, or HtoH motor.

Yes, a polariser can make fine adjustments, but it really only makes a real difference on fringe satellites, or perhaps inclined orbit satellites.

What motor do you have, as you don't say. :)
 

satbadger1

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Thanks guys for the info.
Rolf, not realy sure what the motor is as its been on the wall for years when I bought it with an anologue Drake 250e. It is what i think is a H to H motor?
Would that make a difference to the skew?
 

rolfw

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An HtoH motor follows the arc and the dish is tilted as it drops below the zenith, which in turn skews the LNB, a polariser aside from basic switching between vertical and horizontal, can also make marginal adjustments in skew, a universal LNB switches polarity using a voltage change via the LNB coax cable... :)
 

satbadger1

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Thanks Rolf.
Yes noticed the LNB does skew. So my reciever is automaticaly changing the skew via the coax then?
So basicaly to sum up I dont need the polariser connected unless I need to make fine adjustment for a weak tp?

Cheers :)
 

rolfw

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The LNB is skewed by the movement of the dish, the polarising from horizontal to vertical is changed via the voltage switching via the coax.
 
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