C band feed horn

[WyrTwister]

On a Chaparrel C band feed horn with LNB , scalar ring and polarotor , does the assembly orient with the polarotor at 12 oclock & the LNB at 6 oclock ?

Trying to get the initial mechanical / rotational polarity set correctly .

Thanks ,
Wyr

 

[Shawn95GT]

On my Chaparrel feedhorn it looks like it was installed with the LNB 45° to the vertical axis. I'm not currently using this feedhorn.

There was some talk of this on the forum here and the understanding i got was that the intent was to keep form hitting the limits of adjustment to help the longevity of the servo motor.

What I did was tune a 'known' H or V TP and tweaked the feed horn so that it was optimal for that polarity.

 

[mkm4]

On a Chaparrel C band feed horn with LNB , scalar ring and polarotor , does the assembly orient with the polarotor at 12 oclock & the LNB at 6 oclock ?

Trying to get the initial mechanical / rotational polarity set correctly .

Thanks ,
Wyr

Chapparal Feedhorn FAQ

Rotate the feed to it's proper orientation using the "polar axis template". The polar axis is a line that runs through the center of the dish pivot points. It is the axis around which the dish will rotate. Another way to look at it is ......If your dish is positioned so that it is pointing at it's highest point of travel (the zenith of the arc).......when you stand directly in front of the dish, the "polar axis" runs from 12 o'clock to 6 o'clock. Proper orientation in these terms means that you point the arrow of the polar axis template at 12 o'clock (directly in line with the axis). If you do not have a template, you can get close by siting down the long side of the servo motor; pointing it at about 11 o'clock.

 

[WyrTwister]

Chapparal Feedhorn FAQ

Thank you ,

Wyr
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Updated Friday

I did some tweeking on the 90 cm dish w/ C band scalar ring , feed horn , polar rotor & 15 degree LNB .

AMC 4 is my due south sat . I am picking up 2 network feeds on analog C band . Both have sparkles in the picture , one less so than the other . There is a 3rd TP listed as analog on lyngsat.com , but not getting anything on it .

So far , nothing on DVB-S C band .

Later,
Wyr

 

[youre ugly]

you make a good point

 

[WyrTwister]

you make a good point

By now , I think I have picked up most / all the " full time " analog channels ( a bunch more channels listed on lyngsat.com are named as feeds ) , pretty much east to west .

Using the HH100 to sweep the sky .

Channels vary from a few that are almost as good as over the air channels on rabbit ears to so bad as to barely be able to tell there is a picture there . Most are some where in between .

Although , I think the worst channels are simply bleed over from sats to the east & west of the one I am aimed at . If that is correct , I would say that they do not count .

Again , no DVB-S , yet .

Have a couple more things to test , but if they do not yeald enough improvement to give me DVB-S , then I would have to say I will need to scrounge another , larger dish .

For now , I will have to re-tweek the dish / motor assembly . It seems the wind has rotated the dish out of allignment . They are mounted on a short piece of 2" galvanixed steel pipe that is not in the ground very far ( no concrete ) . The whole pole will turn .

Think I may use this to my advantage . Clamp a 4 ' - 5' steel bar to the pipe , at ground level . This will keep it from rotating when I do not want it to , but allow me to rotate it in very fine incriments , when I am trying to tweek the dish .

Also , the dish to motor alignment is not quite right . I measure from the flat of the motor mount bracket ( that clamps to the pipe ) to a flat spot on the dish bracket , on both the east and the west side & compare measurments .

Problem I am having , is the slack in the motor arm . I think I will mark the dish elevation & then let the dish " droop " down . Hopefully , this will put the weight of the dish " down " & allow the dish to fall to the middle of the slack ?

As it is , with the dish angled up , even at zero position ( midway in the east - west rotation ) , the dish may fall east or west in the slack .

Latter ,
Wyr