Lnb

[gabshere]

ok lnb for the c band , i bought a couple and have to ask a question since i don't have a lot of experince with the corotor is it usually for one freq like H or V and the corotor / polorotor changes it to the other or what.
thanks

 

[voomvoom]

Yes, you've pretty much hit the nail on the head. The servo motor turns the probe inside of the Corotor about 90*. I think mine turns closer to 100*. I read a long time ago that different servo's may vary with the spread, but as long as it's close, it should be OK.

Al

 

[gabshere]

ok thanks
i was looking for the unit to turn... but didn't think that it might be internally. its covered up with the blue cover. guess this is about the same way with skew it moves it left or right via that motor.

I bought several ku lnb's to try with my feedhorn and to play with my primestar dish . although when i mounted it out on the primestar i only got H , so i figure if i rotate the lnb 90 that i will only get V.

 

[Steveo]

Gramma

Ah, the corotor with dreaded blue box. A nice period piece. Have one here but it's never been that succesfull. Pulled it apart to see how it all works. The small probes near the opening of the waveguide are for the Ku side. Large one for the low band and the smaller for the the high. These are connected to the Ku cavity by means of a thin copper tube, kind of like hard coax cable. You will see the the Cband probe at the back of the waveguide. Natually enough there is a few comprimises built into somthing like this as tries to be all things. Some have a plate at the front for Circular Pol. as well. If you don't want to recieve Circulal Pol signals it's best to remove this plate it will improve the Cband performance.
I'm not familliar with your receivers but to make is sucessfully work you will need a reciever with 0-5v-pulse. terminals. If you do hook the thing up to a box like that be carefull you don't get the wires around the wrong way.
Red wire +5vdc. Black wire -0 and white wire pulse_n_

 

[linuxman]

Hey George,

That is the exact same setup that I am using on my Birdview and Winegard. A Corotor II with a C-Band LNB and a Ku Band LNB.

You will need a Pansat 3500 or 2700 to work the polarity changes and skew. Your 4DTV receiver has it built in too.

They work fine as you can see from the SQ that I am getting. You will have to fine tune the dish and make slight adjustments to the Focal distance of the dish to make it work properly. Once that is done, they work great for me.

Fred