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H2H means the drive can move the dish roughly 180 degrees. Some of the old polar mount BUDs could only do 120-140. For the rest look here Footprints by Dish Size - Latitude Declination Chart - C/Ku-Band Satellite Listing

I would suggest that if your dish has an elevation scale, that you use it instead of using an inclinometer. There is no need to over think and use multiple calculations to install a motor! Put away your slide rulers and scientific calculators.........

Simply stated:
1. Set the Motor Latitude Scale to match your Latitude.
2. Set the Dish Elevation Scale to match the Dish Elevation Reading provided in a table with the manual that is provided with a motor.

K.I.S.S.

Now for the GEEK VERSION! (Yes, I may be one of them, so take no offense!)
In order to use an inclinometer, you will first need to know the offset angle of your dish. Subtract the declination angle from the desired setting angle. Example: a GEOSATpro 90cm dish has a 26.6 degree offset angle. If I wanted to set the dish angle to 32.44, I would calculate 32.44 - 26.6 = 5.84.

Set the dish on a perfectly plum and level post. Place a straight edge vertically on the reflector edges (from top to bottom) and place the inclinometer on the the straight edge. If the dish is perfectly vertical, the inclinometer will read 90 degrees. Add 90 + 5.4 = 95.4 degrees. Tilt the dish back so the inclinometer reads 95.4 degrees. If your meter does not read past 90 degrees, flip the inclinometer around and subtract 5.4 degrees from 90 and set the inclinometer reading to 84.6 degrees.

There are other ways to calculate the dish angle if it is already mounted on the motor, but I hope that anyone who has read this thread notes that we are turning two simple mechanical settings of a motor and a dish into a mathematical jamboree............

You Da Man!!

KaptainKlock said:

H2H means the drive can move the dish roughly 180 degrees. Some of the old polar mount BUDs could only do 120-140. For the rest look here Footprints by Dish Size - Latitude Declination Chart - C/Ku-Band Satellite Listing

Click to expand...

Of all the attempts to explain declination you have provided the most helpful and least confussing explanation.

This should be a sticky.

SatelliteAV said:

I would suggest that if your dish has an elevation scale, that you use it instead of using an inclinometer. There is no need to over think and use multiple calculations to install a motor! Put away your slide rulers and scientific calculators.........

Simply stated:
1. Set the Motor Latitude Scale to match your Latitude.
2. Set the Dish Elevation Scale to match the Dish Elevation Reading provided in a table with the manual that is provided with a motor.

K.I.S.S.

Now for the GEEK VERSION! (Yes, I may be one of them, so take no offense!)
In order to use an inclinometer, you will first need to know the offset angle of your dish. Subtract the declination angle from the desired setting angle. Example: a GEOSATpro 90cm dish has a 26.6 degree offset angle. If I wanted to set the dish angle to 32.44, I would calculate 32.44 - 26.6 = 5.84.

Set the dish on a perfectly plum and level post. Place a straight edge vertically on the reflector edges (from top to bottom) and place the inclinometer on the the straight edge. If the dish is perfectly vertical, the inclinometer will read 90 degrees. Add 90 + 5.4 = 95.4 degrees. Tilt the dish back so the inclinometer reads 95.4 degrees. If your meter does not read past 90 degrees, flip the inclinometer around and subtract 5.4 degrees from 90 and set the inclinometer reading to 84.6 degrees.

There are other ways to calculate the dish angle if it is already mounted on the motor, but I hope that anyone who has read this thread notes that we are turning two simple mechanical settings of a motor and a dish into a mathematical jamboree............

Click to expand...

the problem is that I have to do measures after putting the motor, due to inverted motor installation so basically I will need to add this extra declination degrees after I put the dish (correct me if I'm wrong)

http://www.satelliteguys.us/free-ai...seqc-motor-opposite-way-look-pics-inside.html

enb141 said:

the problem is that I have to do measures after putting the motor, due to inverted motor installation so basically I will need to add this extra declination degrees after I put the dish (correct me if I'm wrong)

http://www.satelliteguys.us/free-ai...seqc-motor-opposite-way-look-pics-inside.html

Click to expand...

Enb,

I think that this is part of the reason that it is becoming confusing.

Don't invert the MOTOR, invert the dish panel on its mounting bracket instead. It appears from your pictures that the mounting bracket bolt pattern for the dish reflector panel is symmetrical. So you should be inverting your dish instead of the motor.

You will have to use Brian's (Satellite AV's) instructions to align the dish elevation in this case as your dish elevation scale will now be inverted and therefore unintelligible.

If you want to avoid all this confusion entirely, get a STAB motor which will fit your dish mount so that everything will be normal and all the scales will be proper.

Sorry, I didn't put your other post together with this one, so it confused me when you started mentioning an inverted motor mount.

I understand your direction now, good thing you added the link to your previous post. With this information, I say install the motor normally, as it is intended to be and make the compensations for the dish mount with the dish alone. Other's have done this including myself and it is the better way to proceed. Much easier!

RADAR

AcWxRadar said:

Enb,

I think that this is part of the reason that it is becoming confusing.

Click to expand...

confusing is right! My head is spinning trying to understand what people are saying in these two threads.

AcWxRadar said:

Don't invert the MOTOR, invert the dish panel on its mounting bracket instead. It appears from your pictures that the mounting bracket bolt pattern for the dish reflector panel is symmetrical. So you should be inverting your dish instead of the motor.

Click to expand...

I'm not sure that it's possible for the bolt pattern to be symmetrical, other than from left to right, because from top to bottom, the dish itself isn't symmetrical. It might be possible to flip the dish, but it also might put stress on it and warp it, because even if the spacing is the same, the angles of the surface where the bolts attach will be different.

However, I'm also trying to understand what's being suggested here compared to the OP's issue.
I guess what's confusing me is that I thought the OP had a downward facing motor, like the SG2100, etc, but that his dish requirred the shaft to come in from the bottom??? If that's the case, then inverting the dish in it's bracket alone won't help, because he'd still not be able to get the shaft into the bracket, unless either the bracket was inverted or the motor was inverted.
Putting aside for a minute the issues of getting the right angles, it seems like to even get the dish connected you have 8 options:
(1) Invert the motor, leave the dish and dish mount as is.
(2)Invert the motor, leave dish mount as is, invert dish in mount.
(3)Leave motor as is, invert dish mount, leave dish normal in mount.
(4)Leave motor as is, invert dish mount, invert dish in mount.
(5)-(8) Same as above, but invert the motor shaft (if this is possible with the specific motor), so that the bend tilts up instead of down in normal position.

Now, the actual declination needed is ~ -2.1 degrees (neg meaning down toward the southern horizon). A motor like the SG2100 has a built in declination of about -30 or -35, etc, depending upon model and shaft option, via the bent shaft. To get the proper declination, you need to use a positive dish elevation so that adding the two adds up to the proper declination. Now, if you invert the motor, the declination created by the downward sloping shaft will now be an upward, positive angle rather than down, unless you reverse the shaft coming out of the motor.
Also, the offset dish design involves an offset in the 20-30 deg range, meaning that relative to the connection points of the mount at the back of the dish, the dish is actually aiming about 25 deg higher than it appears. This angle is incorporated into the dish elevation scale if you don't invert it, however it will be aiming ~50 deg too low (relative to the scale) if you do invert it, and this 50 degrees will in effect be a fixed declination that will have to be compensated for by the dish elevation, and has to be incorporated into the calculation, which is difficult since some dish manufacturers don't have accurate specs for offset angle.
Now, the dish elevation angle. Due to the offset design, most offset dish mounts won't go below about 15 deg on the elevation scale. I'm not sure how high they go, but they can be closer to 90 than they are to zero. This dish elevation is positive if the mount is in the normal orientation, and negative if the mount is inverted.


NOW, the possible declination angles from all these options.....

motor.......dish in mount........mount.......motor shaft

1 inverted.......as is.................as is.............as is
2 inverted......inverted.............as is...............as is
3 as is............as is................inverted..............as is
4 as is...........inverted...........inverted...............as is
5 inverted.......as is.................as is................inverted
6 inverted......inverted............as is................inverted
7 as is..............as is...............inverted...........inverted
8 as is........... inverted...........inverted...........inverted



dish in mount......mount........motor shaft.........Total

1 0..............+15 to +80..............-35...............-20 to +45
2 -50............+15 to +80............ -35...............-70 to -5
3 0................-15 to -80..............-35..............-115 to -50
4 -50...............-15 to -80.............-35............-165 to -100
5 0................+15 to +80 .............35.............+50 to +115
6 -50.............+15 to +80..............35................0 to +65
7 0.................-15 to -80............... 35..............-45 to +20
8 -50...............-15 to -80..............35...............-95 to -30

Since we need -2.1 ,

1 Should work.
2 Might work if mount goes above 80
3 Will NOT work.
4 Will NOT work.
5 Will NOT work.
6 Might work if 30 deg shaft.
7 Should work.
8 Will NOT work.

So the options most likely to work would be
(1) Invert the motor, leave the dish and dish mount as is.
and
(7) Leave motor as is, invert dish mount, leave dish normal in mount reverse motor shaft so it tilts other way.

And options (2) and (6) might possibly work depending on the range of the dish elevation and/or the shaft angle on the motor.

WOW, my head is spinning..............