Invacom QPH-031 install questions.

[snyper1982]

Just ordered a bunch of new equipment, and want to make sure I am going about this the right way. Here is my setup:
FortecStar 80cm Dish
Invacom QPH-031
SG2100 Motor
Twinhan 102G with MyTheatre 3.38 as my DVB software.

So let me outline the install procedure I plan to take. Calculate and set the motor elevation for my Long(120.7365) and Lat.(37.5846). I came up with 37.58 deg using this calculator(hxxp://satcalculator.freehostia.com). Set the elevation for the dish, which I came up with as 24.03 using the previous calculator. Get it aimed at True South, which acording to my calculations, is a compass reading of 165.75, taking into account the magnetic declanation for my area.

Hook up the QPH-031 to the Diseqc switch(Port 1 for Circular, and Port 2 for linear). From Diseqc to motor, and from motor to 102G. Go into mytheatre, and point it to the most southerly sat(which is Echo 9, 121W). From here, I am a bit confused. I believe I need to make sure it is tracking the belt correctly though, and to do that I need to try to hit the most easterly bird I can? How do I know which is the most easterly bird I can hit? Anyways, If it is tracking the belt correctly, I am golden, if not, I don't really know what steps to take next.

Oh yeah, and before I forget, in the software, I need to set up my sats individually I assume, and on the linear Sats, I will set it to Diseqc port 2, and have an LOF setting of 10750(can't remember off the top of my head)? And for the circular sats, I need to set it to diseqc port 1 with an LOF 12350(again, can't remember off the top of my head).

If you could guys could go over that, I would be especially greatful. Especialy for anyone that has set up a motor using MyTheatre before. Their input would be most helpful, but any input is greatly appreciated.

One last thing, I downloaded some software for sat aiming, the name escapes me, but I will update this thread tomorrow with the name. Anyways, It gives you azimuth and elevation angles for every sat, as well as has a built in sun azimuth charter. You enter long and lat, and it will give you a list of all the sats, with the azimuth and elevation angles for your location, and in another tab, you enter your time zone, and it will give you in 1 minute intervals, the azimuth of the sun from your position. I am thinking of using this to aim my dish. Just hang a weighted string from the center of LNB holder, and line up the shadow of the string with main mounting mast at the time of day when the sun is at 180 degrees)Or closest to it). That should have me aiming at due south, unless I am mistaken. Anyways, what do you think of this aiming method?

[wejones]

Originally Posted by snyper1982

...
So let me outline the install procedure I plan to take. Calculate and set the motor elevation for my Long(120.7365) and Lat.(37.5846). I came up with 37.58 deg using this calculator(hxxp://satcalculator.freehostia.com). Set the elevation for the dish, which I came up with as 24.03 using the previous calculator. Get it aimed at True South, which acording to my calculations, is a compass reading of 165.75, taking into account the magnetic declanation for my area.

Not particularly important, but I'd recommend using approximately 0.6 degrees more for you latitude setting (ie 38.2), and 0.6 degrees less for your declination (which you used to calculate the 24.03, so that number would be 0.6 degrees higher as well).
Also, if you just purchased the SG2100, make sure what the bend in the shaft is. There are apparently two versions, one with a 30 deg angle , dish elevation =30-declination, and one with a 35 deg angle, ie dish elevation =35-declination.

Originally Posted by snyper1982

Hook up the QPH-031 to the Diseqc switch(Port 1 for Circular, and Port 2 for linear). From Diseqc to motor, and from motor to 102G. Go into mytheatre, and point it to the most southerly sat(which is Echo 9, 121W). From here, I am a bit confused. I believe I need to make sure it is tracking the belt correctly though, and to do that I need to try to hit the most easterly bird I can? How do I know which is the most easterly bird I can hit? Anyways, If it is tracking the belt correctly, I am golden, if not, I don't really know what steps to take next.

On your south sat, peak that sat using dish elevation alone. When you go to the most easterly (it doesn't matter which one), peak on the sat by moving the whole mount on the pole (ie your true south alignment), *PLUS* motor the dish back and forth through the sat after each adjustment, to find the best signal. Don't touch any elevations, except while on your south sat.

Originally Posted by snyper1982

Oh yeah, and before I forget, in the software, I need to set up my sats individually I assume, and on the linear Sats, I will set it to Diseqc port 2, and have an LOF setting of 10750(can't remember off the top of my head)? And for the circular sats, I need to set it to diseqc port 1 with an LOF 12350(again, can't remember off the top of my head).

11250, not 12350.

Originally Posted by snyper1982

If you could guys could go over that, I would be especially greatful. Especialy for anyone that has set up a motor using MyTheatre before. Their input would be most helpful, but any input is greatly appreciated.

I've never aligned a dish using MyTheatre. I'm not sure how easy that would be, because most computer programs are pretty un-responsive with respect to signal strength meters. I'm not sure if this program works for the 102g, but I've used a program called THMOVER, which has a signal strength meter that works better than most programs. THMOVER works pretty well with the Twinhan 1020a, so it might work with the 102g.
Hans, the guy who wrote it, doesn't have his web page up anymore, but you can find the program at:
http://web.archive.org/web/200706251...hmover1003.exe

Originally Posted by snyper1982

One last thing, I downloaded some software for sat aiming, the name escapes me, but I will update this thread tomorrow with the name. Anyways, It gives you azimuth and elevation angles for every sat, as well as has a built in sun azimuth charter. You enter long and lat, and it will give you a list of all the sats, with the azimuth and elevation angles for your location, and in another tab, you enter your time zone, and it will give you in 1 minute intervals, the azimuth of the sun from your position. I am thinking of using this to aim my dish. Just hang a weighted string from the center of LNB holder, and line up the shadow of the string with main mounting mast at the time of day when the sun is at 180 degrees)Or closest to it). That should have me aiming at due south, unless I am mistaken. Anyways, what do you think of this aiming method?

Many web pages to give you the time of local noon, and yes, this is probably the best way to line up to true south, assuming that your lnbf arm isn't bent. What you are really trying to line up with south is your mount, not the dish, so if you can find a flat surface on the motor to aim to the south direction you find via the sun, you might be better off. But you'll still probably have to peak on sat signals to get it perfect.

[snyper1982]

Originally Posted by wejones

Not particularly important, but I'd recommend using approximately 0.6 degrees more for you latitude setting (ie 38.2), and 0.6 degrees less for your declination (which you used to calculate the 24.03, so that number would be 0.6 degrees higher as well).
Also, if you just purchased the SG2100, make sure what the bend in the shaft is. There are apparently two versions, one with a 30 deg angle , dish elevation =30-declination, and one with a 35 deg angle, ie dish elevation =35-declination.

Actually, I didn't calculate it at all the web page I linked to gave both latitude and dish elevation.

Originally Posted by wejones

On your south sat, peak that sat using dish elevation alone. When you go to the most easterly (it doesn't matter which one), peak on the sat by moving the whole mount on the pole (ie your true south alignment), *PLUS* motor the dish back and forth through the sat after each adjustment, to find the best signal. Don't touch any elevations, except while on your south sat.

This part is confusing me. When you say motor the dish back and forth through the sat, are you meaning motor it to the 121 sat and back to the easterly sat? Not sure what you are getting at there.

Originally Posted by wejones

11250, not 12350.

Thanks

Originally Posted by wejones

I've never aligned a dish using MyTheatre. I'm not sure how easy that would be, because most computer programs are pretty un-responsive with respect to signal strength meters. I'm not sure if this program works for the 102g, but I've used a program called THMOVER, which has a signal strength meter that works better than most programs. THMOVER works pretty well with the Twinhan 1020a, so it might work with the 102g.
Hans, the guy who wrote it, doesn't have his web page up anymore, but you can find the program at:
http://web.archive.org/web/200706251...hmover1003.exe

Thanks again.

Originally Posted by wejones

Many web pages to give you the time of local noon, and yes, this is probably the best way to line up to true south, assuming that your lnbf arm isn't bent. What you are really trying to line up with south is your mount, not the dish, so if you can find a flat surface on the motor to aim to the south direction you find via the sun, you might be better off. But you'll still probably have to peak on sat signals to get it perfect.

The software is called Satellite Antenna Alignment, by AL-Software. It is a really nice program. I bought a couple of other things when I ordered my stuff. Like an inclinometer, and a SC10S Satellite Meter Kit Satellite Finder(comes with a compass as well), to help make my install a bit easier. I have a level already, but I assume I can use the inclinometer in place of the level?

[wejones]

Originally Posted by snyper1982

Originally Posted by wejones
Not particularly important, but I'd recommend using approximately 0.6 degrees more for you latitude setting (ie 38.2), and 0.6 degrees less for your declination (which you used to calculate the 24.03, so that number would be 0.6 degrees higher as well).
Also, if you just purchased the SG2100, make sure what the bend in the shaft is. There are apparently two versions, one with a 30 deg angle , dish elevation =30-declination, and one with a 35 deg angle, ie dish elevation =35-declination.

Actually, I didn't calculate it at all the web page I linked to gave both latitude and dish elevation.

Then even more reason to be careful. What you should be doing, is first calculate your declination. Most tables will tell you that for your latitude to use a declination of 5.99, however this is a rather crude approximation. You should use 5.30. Then, subtract this declination from the bend angle in the motor shaft. The old SG2100 motors had a 30 deg bend, so 30-5.99=24.01 (pretty much what you're quoting), however the newer SG2100s have a 35 degree bend, which means 35-5.99=29.01. So you have to figure out which motor shaft you have. And again, I'd recommend using 5.3 instead of 5.99 as your declination, but if you do that, you need to use 38.3 for your latitude setting instead of 37.6.

Originally Posted by snyper1982

Quote:
Originally Posted by wejones
On your south sat, peak that sat using dish elevation alone. When you go to the most easterly (it doesn't matter which one), peak on the sat by moving the whole mount on the pole (ie your true south alignment), *PLUS* motor the dish back and forth through the sat after each adjustment, to find the best signal. Don't touch any elevations, except while on your south sat.

This part is confusing me. When you say motor the dish back and forth through the sat, are you meaning motor it to the 121 sat and back to the easterly sat? Not sure what you are getting at there.

No,all the back and forth is at the easterly sat. Ie, I'm saying motor to the easterly sat, get a signal quality reading, then make an adjustment by moving the entire mount on the pole, then bump the motor back and forth very small amounts, trying to find the best signal. When you find the best signal quality, compare this reading to what you had originally. If better, adjust more in that direction, if worse, adjust in the other direction, then bump motor back and forth in small steps, and again compare your best reading to your original. It will take a few back and forths, but once you get the best possible signal at the easterly sat, you should be done.
There are some other ways of doing this, but if you start out with the proper declination and motor elevation, and then spend a little more time working on your easterly sat, things will end up taking you much less time in the long run.

Originally Posted by snyper1982

..... I bought a couple of other things when I ordered my stuff. Like an inclinometer, and a SC10S Satellite Meter Kit Satellite Finder(comes with a compass as well), to help make my install a bit easier. I have a level already, but I assume I can use the inclinometer in place of the level?

Yeah, probably. I think a good level is more accurate than an inclinometer, but I think the inclinometer is easier to use. With these small dishes, you mainly use it on the pole, and on the motor itself, but it won't help much on the dish elevation, since there is no surface that corresponds to the direction the dish is actually looking. With a big dish, you can do all three with the inclinometer.

[snyper1982]

Originally Posted by wejones

Then even more reason to be careful. What you should be doing, is first calculate your declination. Most tables will tell you that for your latitude to use a declination of 5.99, however this is a rather crude approximation. You should use 5.30. Then, subtract this declination from the bend angle in the motor shaft. The old SG2100 motors had a 30 deg bend, so 30-5.99=24.01 (pretty much what you're quoting), however the newer SG2100s have a 35 degree bend, which means 35-5.99=29.01. So you have to figure out which motor shaft you have. And again, I'd recommend using 5.3 instead of 5.99 as your declination, but if you do that, you need to use 38.3 for your latitude setting instead of 37.6.

I already did that. Then used that page and it came up with nearly the exact same calculations I did. So I figured what the heck, I will just use it. Anyways, How do you go about calculating the declination, because all I have seen was charts with latitude. Since my lat is pretty close to a half a degree, I added the declination for 37 lat and the declination for 38 lat, and divded that number by 2. I came out with 24.04, the calculator I used came out with 24.03.... I appreciate your help, but I am curious as to where you are getting your numbers, and what makes them better than the other numbers that the calculators give? Dish Elevation: 24.03

Originally Posted by wejones

No,all the back and forth is at the easterly sat. Ie, I'm saying motor to the easterly sat, get a signal quality reading, then make an adjustment by moving the entire mount on the pole, then bump the motor back and forth very small amounts, trying to find the best signal. When you find the best signal quality, compare this reading to what you had originally. If better, adjust more in that direction, if worse, adjust in the other direction, then bump motor back and forth in small steps, and again compare your best reading to your original. It will take a few back and forths, but once you get the best possible signal at the easterly sat, you should be done.
There are some other ways of doing this, but if you start out with the proper declination and motor elevation, and then spend a little more time working on your easterly sat, things will end up taking you much less time in the long run.

So you mean, move the motor+dish setup once I get to the easterly sat, and peak the signal there?

Originally Posted by wejones

Yeah, probably. I think a good level is more accurate than an inclinometer, but I think the inclinometer is easier to use. With these small dishes, you mainly use it on the pole, and on the motor itself, but it won't help much on the dish elevation, since there is no surface that corresponds to the direction the dish is actually looking. With a big dish, you can do all three with the inclinometer.

That is what I figured. I will make sure that the mount is straight, and try to get the motor angle correct using the inclinometer.

Thanks again for your help.

[wejones]

Originally Posted by snyper1982

I already did that. Then used that page and it came up with nearly the exact same calculations I did. So I figured what the heck, I will just use it. Anyways, How do you go about calculating the declination, because all I have seen was charts with latitude. Since my lat is pretty close to a half a degree, I added the declination for 37 lat and the declination for 38 lat, and divded that number by 2. I came out with 24.04, the calculator I used came out with 24.03.... I appreciate your help, but I am curious as to where you are getting your numbers, and what makes them better than the other numbers that the calculators give? Dish Elevation: 24.03

There are charts that cover what I'm referring to. Look at:
Footprints by Dish Size - Latitude Declination Chart - C/Ku-Band Satellite Listing
At this page, there is a chart for declination and a chart for "modified" tracking angles, which is the more accurate values. (Note, this chart incorrectly refers to the latitude value as being an elevation, when actually the elevation is 90 minus this value).

The declination of a sat to your south is very easy to calculate, which is why most charts (such as you'll find on the Sadoun site) use these values. I just drew up a little picture describing the calculation.



Basically, the declination angle is the "d", which is described by a right triangle with one side being the distance above the earth's equatorial plane you are located ( "A"), and the other side being the distance to the sat in the equatorial plane, ( H + C ).

The problem is that the declination of sats toward either your east or west horizon is less, up to about 0.6 degrees less, so if you use the south declination, you will be off by up to 0.6 degrees in your aim on other sats. I drew another diagram from the perspective above the north pole with south up.


For sats not to your south, the declination calculation still has the same "A" dimension, however the ( H + C ) dimension has increased, which is what causes the declination angle to get less. BTW, the DL angle is the delta longitude, ie the difference between the sat's longitude and your longitude, and the U angle is the so called USALS angle, ie the actual angle that the motor shaft has to turn to go to a satellite. But back to the declination, I can't remember the equations off hand, but I always look up the equation for calculating the angles of a non-right triangle, given two sides and an angle. Years ago I used to just spit that out from memory, but with age, I generally struggle for hours trying to do the calculations.
HOWEVER, a pretty good approximation for the declination angle for sats to your east or west is obtained by using ATAN ( A/(H+RE) ).
Basically, if you use this smaller declination, you have to increase the latitude setting on your motor by the difference between the south declination and the east/west declination, and this will correct the setting on south satellites, and the motor elevation's effect decreases proportionally as you motor east or west since it is orthogonal, so it is still correct to the east or west.

Originally Posted by snyper1982

So you mean, move the motor+dish setup once I get to the easterly sat, and peak the signal there?

Yeah, I think that's what I mean. Basically, *IF* the true south alignment was done properly, you won't have to do this adjustment, but usually you'll be off a bit. Also, if your motor is properly calibrated re the zero position, then you won't need to do the motoring back and forth after each adjustment, but I've found that my SG2100 was not calibrated properly.

[snyper1982]

Originally Posted by wejones

There are charts that cover what I'm referring to. Look at:
Footprints by Dish Size - Latitude Declination Chart - C/Ku-Band Satellite Listing
At this page, there is a chart for declination and a chart for "modified" tracking angles, which is the more accurate values. (Note, this chart incorrectly refers to the latitude value as being an elevation, when actually the elevation is 90 minus this value).

The declination of a sat to your south is very easy to calculate, which is why most charts (such as you'll find on the Sadoun site) use these values. I just drew up a little picture describing the calculation.



Basically, the declination angle is the "d", which is described by a right triangle with one side being the distance above the earth's equatorial plane you are located ( "A"), and the other side being the distance to the sat in the equatorial plane, ( H + C ).

The problem is that the declination of sats toward either your east or west horizon is less, up to about 0.6 degrees less, so if you use the south declination, you will be off by up to 0.6 degrees in your aim on other sats. I drew another diagram from the perspective above the north pole with south up.


For sats not to your south, the declination calculation still has the same "A" dimension, however the ( H + C ) dimension has increased, which is what causes the declination angle to get less. BTW, the DL angle is the delta longitude, ie the difference between the sat's longitude and your longitude, and the U angle is the so called USALS angle, ie the actual angle that the motor shaft has to turn to go to a satellite. But back to the declination, I can't remember the equations off hand, but I always look up the equation for calculating the angles of a non-right triangle, given two sides and an angle. Years ago I used to just spit that out from memory, but with age, I generally struggle for hours trying to do the calculations.
HOWEVER, a pretty good approximation for the declination angle for sats to your east or west is obtained by using ATAN ( A/(H+RE) ).
Basically, if you use this smaller declination, you have to increase the latitude setting on your motor by the difference between the south declination and the east/west declination, and this will correct the setting on south satellites, and the motor elevation's effect decreases proportionally as you motor east or west since it is orthogonal, so it is still correct to the east or west.

Uhh, thanks, I think.... LOL. That was a bit to much for me. Haha. Thanks for trying though. Could you give an example of what you mean here regarding the smaller declination? Like walk me through the calculations I would have to do with at my lat and long?

Originally Posted by wejones

Yeah, I think that's what I mean. Basically, *IF* the true south alignment was done properly, you won't have to do this adjustment, but usually you'll be off a bit. Also, if your motor is properly calibrated re the zero position, then you won't need to do the motoring back and forth after each adjustment, but I've found that my SG2100 was not calibrated properly.

Hmm. I hope mine is calibrated properly. Even so, i suppose I will have to peak the signal anyways, as I will in all likelihood not be able to get it dead on.

[wejones]

Originally Posted by snyper1982

..... Could you give an example of what you mean here regarding the smaller declination? Like walk me through the calculations I would have to do with at my lat and long?
..

Before getting into the "smaller declination", intent in alignment is to have the motor axis pretty close (not exactly) to being parallel to the earth's rotation axis, ie pointed at the north star (this is done with the motor elevation adjustment). Without declination, the dish would look out in a plane parallel to the earth's equatorial plane, but several thousand miles above it (ie the "A" distance). In order to point at the satellites, the dish has to be lowered by the declination angle, otherwise it would be pointed above all the sats.
The problem is, that (what I was trying to show with drawings) because we are different distances away from the different satellites, the necessary declination angle will be different for each sat. The maximum declination angle is for the sat to your south {5.99 deg in your case), and sats to your east or west will have a smaller declination angle {about 5.31 in your case}, and the sats in between are in between these two values. A properly aligned system should use the "smaller" {5.31} declination. This will require using a motor elevation setting which is less by the difference in these two numbers, ie by using a latitude setting that is greater than your actual latitude by 0.68 in this case, ie 38.269 instead of 37.5846.
For a small dish on Ku or a big dish on C band, it is probably close enough to just use the south declination {5.99}, and you will probably get acceptable alignment, however if you want to be more precise, it's best to try to start at the desired value, which is the 5.31.
With these small dishes, however, the declination setting (which is accomplished by the dish elevation) is only a starting point. Most people first set the motor elevation, then find the dish elevation by peaking on your south satellite, and if your motor elevation is set at your actual latitude, it will automatically peak on your south declination. So basically, the only thing you need to do is set your motor elevation to 38.269 (or as close to 38.3 as you can), and when you peak on your south sat, it will automatically set your declination to the proper value. No calculations necessary, just set your motor's latitude setting about 0.7 degrees higher than your actual latitude. That's all.

[snyper1982]

Originally Posted by wejones

Before getting into the "smaller declination", intent in alignment is to have the motor axis pretty close (not exactly) to being parallel to the earth's rotation axis, ie pointed at the north star (this is done with the motor elevation adjustment). Without declination, the dish would look out in a plane parallel to the earth's equatorial plane, but several thousand miles above it (ie the "A" distance). In order to point at the satellites, the dish has to be lowered by the declination angle, otherwise it would be pointed above all the sats.
The problem is, that (what I was trying to show with drawings) because we are different distances away from the different satellites, the necessary declination angle will be different for each sat. The maximum declination angle is for the sat to your south {5.99 deg in your case), and sats to your east or west will have a smaller declination angle {about 5.31 in your case}, and the sats in between are in between these two values. A properly aligned system should use the "smaller" {5.31} declination. This will require using a motor elevation setting which is less by the difference in these two numbers, ie by using a latitude setting that is greater than your actual latitude by 0.68 in this case, ie 38.269 instead of 37.5846.
For a small dish on Ku or a big dish on C band, it is probably close enough to just use the south declination {5.99}, and you will probably get acceptable alignment, however if you want to be more precise, it's best to try to start at the desired value, which is the 5.31.
With these small dishes, however, the declination setting (which is accomplished by the dish elevation) is only a starting point. Most people first set the motor elevation, then find the dish elevation by peaking on your south satellite, and if your motor elevation is set at your actual latitude, it will automatically peak on your south declination. So basically, the only thing you need to do is set your motor elevation to 38.269 (or as close to 38.3 as you can), and when you peak on your south sat, it will automatically set your declination to the proper value. No calculations necessary, just set your motor's latitude setting about 0.7 degrees higher than your actual latitude. That's all.

I get it now. Thanks for the extra time going into so much detail. I have a few more questions though, . I downloaded some apps from your page, namely the Sat View app. I did some calculations with it. At my latitude(I used 37) my max declination is 5.91. I subtracted 61.5(My most easterly sat) from 121(my most southerly sat), and came up with a delta longitude of 59.5, rounded it to 60. That makes my minimum declination 5.53. Would that be correct? So now I take my max declination 5.91 and subtract my minimum declination of 5.53, and I come up with .38. so I take my actual latitude(37.5846), and add .38, and I come with 37.9646, or rounded to 38.

Does that sound about right? I don't expect to use any sats farther east than Echo 3 at 61.5. I am getting mixed results on which is actually the furthest east sat I can get. One program says I can get PAS 6B, and PAS 3R at 43W, and another says the furthest I can get is PAS 1R at 45W. The programing on the sats further east are of no interest to me anyways, so it is a moot point.

[wejones]

I think I would use the 5.31 even if you can't get to a sat with that declination, because there is still a slight contribution from the motor elevation at sats you can actually see (I know that probably doesn't make sense).
But realistically, it probably doesn't make a whole lot of difference, because both are probably so close to each other that you can't tell the difference, plus you probably can't set or measure the angles that accurately anyway. I think my main goal would be (1) with a big dish, set the declination to less than the south declination by something a bit more than a half degree, or (2) with a small dish, set the motor latitude setting to more than your actual latitude by a bit more than a half degree. Basically, when you set these angles, it's usually not possible to set it to a precision of tenths of a degree, you can usually just get close to the nearest half degree. I see people setting their latitude setting, and rounding off to the low side, but they would be better off rounding off to the high side. As long as you get to within a few tenths of a degree, I don't think you'll be able to see a difference.