Dish elevation angle (again?)

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Tron

SatelliteGuys Master
May 6, 2005
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Metro New Orleans, LA
It is also essential to be sure that the dish is square with the motor shaft. By square, I mean that the center of the dish has to line up exactly with the center of the motor shaft. If you look at the motor and dish from above, and imagine a line drawn across the front of the dish from left to right, and another line going through the motor from front to back, those two lines should form a perfect 'T'. This is especially important to check for on dishes like the WS9036, which use a U-Bolt-style mount, and therefore could be bolted to the motor shaft facing to the left or to the right of dead center.
 

andrew_h

Active SatelliteGuys Member
Mar 25, 2011
15
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Illinois
Reporting back after the install:

In short: it was a success; not as difficult as I originally thought it would be (or maybe I was plain lucky). In any case, all the information shared in this thread (and numerous others) helped tremendously in reducing the guesswork.

As far as dish elevation is concerned, I completely ignored the declination angle & motor pipe angle calculation. Once I mount the motor+dish assembly on the perfectly plumb mast & aimed it to true south (using magnetic compass + correction), I adjusted the dish elevation to the elevation of the satellite nearest to true south (measuring at dish face with a digital level). Galaxy 28 is at 41.5 deg, so the dish elevation is 16.9 deg (i.e. 41.5 less 24.6 dish offset). Following one of the suggestions on this thread, from the receiver I moved the dish to point to Galaxy 28 - received 80% signal strength from TP 11955 V.
Physically moving the dish left & right caused signal strength to drop. Adjusting the dish elevation had the same effect - so the original elevation calculation was dead on.

It survived strong wind gust yesterday & last night, I am glad I decided to use 1 7/8" black pipe instead of the J-pipe that came with the dish.
 

zamar23

SatelliteGuys Pro
Feb 5, 2009
1,204
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Mid West
If you're still inclined to use the motor you purchased, your dish mounting approach on a polar mount is incorrect at best. After you'll have a hard time trying to find other sats closer to your arc limits, you need to re-read what others are posted about polar mount setup. Even after you exactly following their instructions (instead of making your own), you'll still need to make some adjustments of elevation and declination angles to compensate for scale print errors (or lack of such) and inaccuracies in approximate polar mount angles calculation.
 
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andrew_h

Active SatelliteGuys Member
Mar 25, 2011
15
0
Illinois
I don't believe what I have is "polar mount"... I mount the whole assembly on a vertical pole so it's no different than mounting it on a J-pipe.
Still in learning mode, so it is very likely that I missed something here.
 

zamar23

SatelliteGuys Pro
Feb 5, 2009
1,204
1
Mid West
As far as dish elevation is concerned, I completely ignored the declination angle & motor pipe angle calculation.

If you hooked your dish on an angled (30 deg in your case) motor shaft - this is your polar mount. The way you used so far to angle the dish, you can only scan sats around your due south. There is a reason, why several different angles are mentioned in install manuals. Believe it or not - they're still not accurate enough, but some software can adjust angle values so that you don't have to struggle trying to find the right angles to catch all sats along visible arc. For starters, you need to learn, how to follow existing manuals... :)
 
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andrew_h

Active SatelliteGuys Member
Mar 25, 2011
15
0
Illinois
Yup, was able to pick up channels from sats within +/- 20 degrees, most with good signal strength & quality. I will try to scan far east/west sats later this week.

Is the information in Lyngsat pretty current/accurate in general? my receiver only picks up 2 channels from AMC21 (can't remember from which TPs, but both shows great signal quality), I wonder if my setup is off, or if Lyngsat is outdated.
 

andrew_h

Active SatelliteGuys Member
Mar 25, 2011
15
0
Illinois
andrew_h

If you hooked your dish on an angled (30 deg in your case) motor shaft - this is your polar mount. The way you used to angle the dish, you can only scan sats around your due south. :)

Thanks zamar23 - let me do more reading. At this point to be honest I think the final setup (i.e. where the dish is pointed etc) between the 2 methods is the same. The difference is how I get there; instead of setting the dish elevation angle on the dish bracket (based on latitude & declination & motor angle), I chose to do it by measuring the actual elevation, on the face of the dish.
 

Tron

SatelliteGuys Master
May 6, 2005
6,599
33
Metro New Orleans, LA
Installing an H-H DiSEqC motor is very easy, provided the motor is absolutely level and the MOTOR elevation is set to your latitude on the LATITUDE side of the motor bracket. The ELEVATION side of the bracket should have a reading that is 90 minus your latitude. For example, my latitude is 30. My motor elevation reads 30 on the LATITUDE side of the motor bracket, and 60 on the ELEVATION side of the motor bracket.

Once you are confident that the motor is level and its elevation is set to your latitude on the LATITUDE scale, point the whole assembly (motor and dish) generally toward due South. Power up the receiver, set up on a satellite near due South to you, and select USALS in the motor settings. Input your longitude and latitude on the receiver, then save. The receiver will move the motor and dish to where it thinks the satellite is, based on your inputted longitude and latitude. From there, its basically like hitting a satellite on a fixed dish. You just have to adjust the motor and dish assembly East to West (azimuth), and adjust the DISH ELEVATION (don't touch the MOTOR ELEVATION, its set) until you receive a signal.

If you've done these steps properly, you should be tracking the arc. You will want to move the motor to a far Eastern and far Western satellite and make fine adjustments until you get the entire arc perfectly.
 
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zamar23

SatelliteGuys Pro
Feb 5, 2009
1,204
1
Mid West
Radar,

I know... But some ppl like detail explanations, and some are in rush and can't read or remember more than 2-3 sentences. :) The above passage looks like belonging to the "brief" category. And some ppl question "relativity theory" without ever reading it first, despite its freely available and easy to find. :D
 

AcWxRadar

SatelliteGuys Pro
Apr 26, 2006
4,575
4
40 miles NW of Omaha. Omaha?
Radar,

I know... But some ppl like detail explanations, and some are in rush and can't read or remember more than 2-3 sentences. :) The above passage looks like belonging to the "brief" category. And some ppl question "relativity theory" without ever reading it first, despite its freely available and easy to find. :D

Zamar,

I understand and Tron articulated it very well. That's why I gave his post a LIKE vote (I don't give out many). Sometimes it is just "how you phrase it" that makes all the difference in the world.

RADAR
 

Tron

SatelliteGuys Master
May 6, 2005
6,599
33
Metro New Orleans, LA
Thanks for the thoughts guys... It is hard to explain it without being too wordy, even when I've tried on the phone. It is one of those things that is easier to demonstrate than to articulate.

What always takes me the most time when installing a motorized dish is being too "Monkish" (from the TV detective series, it means obsessive-compulsive) about the fine-tuning phase ;) ...
 

zamar23

SatelliteGuys Pro
Feb 5, 2009
1,204
1
Mid West
Fine tuning? This one is pain-in-the-..ss without some adjustment screws, if one has a larger dish. :)
 
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