What is the travel on a HH Motor

[Technojunky]

I have a new motor that is supposed to be HH and the literature with it says that it has a travel of 95 degrees. I would think that HH = 180 degree's, am I wrong? JM

 

[pro96]

I have a new motor that is supposed to be HH and the literature with it says that it has a travel of 95 degrees. I would think that HH = 180 degree's, am I wrong? JM

The 180 degrees HH were the actuator type for C-BAND, the one you have are for FTA receivers which is normal at 95 degrees.

 

[starman345]

If you go to the home pages of the various motors you will see the rotation angles, some call them azimuth angles. The sg2100 is 150 degrees, 75 either side of center. The Stab motors are slightly less. You are correct HH horizon to horizon should be 180 degrees, none of the ones I've seen advertised are. What brand motor do you have? I've never heard of one that only had 95 degrees of travel.

 

[Pepper]

maybe it's saying 95 degrees either side of center? (which would mean it's a really GOOD one)

 

[Shawn95GT]

My Moteck is rated to 70 some odd degrees either way from center.

I was tracking 58w - 148w with it. The motor wouldn't move east of 58w via USALS but 1.2 would go further.

I don't think it really needs to go any further than that because much beyond that point the dish is standing on it's head. At some point at the ends of travel I think the geometry of it goes to crap.

 

[AntAltMike]

Full utilization of a mover that goes 95 degrees to either side would require serious trenching. Like, the Philipines Trench, the Marriana's Trench, etc.

Am polarizer motor might be rated to +/- 95 degrees, since you set it at about 45 degrees and rotate it about + or - 45 to get to horizontal or vertical.

 

[Larry1]

When a motor turns, does 1 degree of turn on the motor equal to one degree on the satellite orbit? If you look at some motors, eg. Stab HH120, it has the scale on the casting of the motor.
see link and picture 4
http://www.sadoun.com/Sat/Products/STAB/HH120-Stab-HH-Diseqc-USALS-Motor.htm
The Stab motor above has a rotation limit of +/- 62 deg, with mechanical limits of +/- 70 deg. I will check this with my motor on the weekend, as I am unable to get to my box untill then. I know with my box, when I change satellites, it gives a dialoge like "moving 15 deg west".
So my question would be.... just because a motor can turn +/- 62 deg., does this meen it can track the satellites 62 degrees either side of my true south satellite? Also, why would you need both the lat and long to enter in the USALS screens?

 

[Larry1]

Found my answer, and a calculator to help you. A 1 deg turn of the HH motor does not equal to a 1 deg change on the satellite arc.
See the following link
http://www.gaaps.com.tw/
As an example, my true south is my longitude, 79.42W. My latitude is 43.7N. To turn from my 0 position (my longitude) to 123.00 calculates out to be 47.9deg which does not equal 123.00-79.42=43.58deg.

 

[barney_555]

My longitude is 71.7 deg and with a SG2100 I can see Telstar 12 at 15 deg to IA-7 at 129 deg.

The maximum travel of a SG2100 is 140 deg. My motor limit are set at 60 deg so I have 120 deg of horizon. And, yes 1 deg on the motor equal 1 deg on the arc.

 

[Larry1]

Using your longitude of 71.7W and for example latitude of 48.5N. (somewhere in Quebec) True south would be 71.7N and this would be your 0 deg.(on the motor) To turn to 129.0W if 1 deg of turn on the motor equals 1 deg. spacing on the satellite arc, then the motor would have to turn 129.0-71.7=57.3deg.. Using the Moteck calculator, the motor has to turn 61.9deg.

 

[Sadoun]

Larry

That calculator might be model specific. It may not apply to every brand or model, since they all have different shaft angle relative to the center of rotation.

When I get a chance, I will check the rotation on the STAB HH100 mounted just outside of our showroom.

 

[rkrenicki]

if you were located in the center of the earth, then yes, 1 degree on your motor would equal 1 degree of satellite seperation

I wonder how those near the equator do it.. it would be a dish pointed straight up into the sky, and would only have to alter one axis, none of this arc crap

 

[Larry1]

Larry

That calculator might be model specific.

If the calculator was model specific, then the IRD would have to be told what rotor you had installed, and not just your location information. Otherwise, the goto x function, would not work with different brands of rotors. I may be proved wrong on this.... but let us know your findings when you check your STAB HH100. I would like to know.

 

[Larry1]

It may not apply to every brand or model, since they all have different shaft angle relative to the center of rotation.

The angle of the bend in the arm of the shaft is only to compensate for the limited adjustments in the dish mounting bracket. The arm could be straight and the motor would still work the same as long as the dish mount had enough adjustment in its mounting bracket. The bend of the arm and the angle of adjustment of the dish mount and the dish offset angle all sum together to make one angle from the motor shaft centre line. (the line of the motor before any bend in the arm... i.e. the axis of the shaft inside of the motor itself) All these angles are in the same plane, so the total angle is the sum of all the angles.
A quick test to point this out.... take a piece of wire. (or even a paper clip will do) A few inches from one end, make a 30 deg bend. This represents the angle of the bend in the motor shaft. A few more inches along the wire in the same plane, make another 30 deg bend. This represents the angle of the dish mount or disk bracket. Again a few more inches along the wire in the same plane, make another 30 deg bend. This represents the offset angle of the dish. If you made all these angles in the same plane, the part of the wire before the first bend and the part of the wire after the last bend will be at an angle that is equal to the sum of the 3 angles, an no matter how you turn the wire, this angle does not change. In this case 30+30+30=90deg. This will work for any angle you bend the wire AS LONG AS ALL THE BENDS ARE IN THE SAME PLANE.
Now a second wire with only a single bend equal to the sum of the three bends, in this case 90deg., will turn the same as the first. It does not matter that one has one bend and the other has three bends.

Hopefully this will make it easier for everyone to understand. I know it did for me when trying to calculate this out.

Thank You....Larry

 

[Sadoun]

I checked the angle of rotation on an HH100 and here are the results:

Our longitude: 83W
Our Latitude: 40N
Rotated dish to HISPASAT at 30W
Result: Indicator on HH100 shaft is at 60 degrees.

According to GAAPS it should be 58.3

Since the scale on the STAB motor has a 5 degrees increments, my reading of the indicator could be wrong. But, the indicator is dead on 60 degrees.