SG2100 Tweak Angle

[rogerduncan100]

Can anybody tell me the answer to this technical question? If I use USALS user mode to move the dish east or west just one jump, how many tenths of a degree does the dish turn?

I am guessing that this property is dependent on the motor only and is not affected by the brand of receiver or whether USALS or DISCEQ is being used.

The reason I ask is because it seems two or three tweaks to the east increases my signal quality on all the satellites and I want to know how much to turn the dish mount to make my setup "more perfect".

 

[Larobpra]

It used to take 16 clicks to go from 72 to 74 with my SG2100, so 8 clicks per degree. That was with a Mercury II receiver using DiSEqc.

One way to test just how many it takes with your setup is to add a hot transponder from a neighboring satellite, then see how many clicks it takes to peak the signal on that TP.

 

[rogerduncan100]

Indeed I can see it makes sense for me to do some experimenting with my system. Thanks for the idea!

 

[AcWxRadar]

Can anybody tell me the answer to this technical question? If I use USALS user mode to move the dish east or west just one jump, how many tenths of a degree does the dish turn?

I am guessing that this property is dependent on the motor only and is not affected by the brand of receiver or whether USALS or DISCEQ is being used.

The reason I ask is because it seems two or three tweaks to the east increases my signal quality on all the satellites and I want to know how much to turn the dish mount to make my setup "more perfect".

Roger,

You have either phrased your question wrong or you aren't understanding the difference between USALS and DiSEqC 1.2 motor control.

USALS does not provide an option to "tweak" the satellite position. That is only allowed in DiSEqC 1.2 motor control mode.
In USALS, th only way to "tweak" the position of the motor/dish is to alter the orbital position of the satellite. i.e. if you are at satellite AMC 9 and have it set to the orbital location of 83.0°W and desire to "tweak" it a bit to try to improve the signal and quality, then you have to adjust the orbital position of AMC 9 to move it. So, instead of 83.0°W, you would have to change the sat position to 82.9°W or 83.1°W or something to that effect.

You cannot go to the DiSEqC 1.2 function and adjust the sat position and then revert to USALS and have the change remain. These are two separate systems and they don't work in conjunction with eachother in that way or in any way.

If your dish and motor are not precisely aligned, the only way to make a compensation for this (beyond the mechanical adjustment) is to use DiSEqC 1.2 and tweak it there. However, the only angle you can tweak in the DiSEqC 1.2 mode is the azimuth position. The dish elevation and the LNBF polarization adjustment are totally separate from this.

I think I understand what you are trying to accomplish here, but you are confused in regards to the motor control options. You see, everyone gets impatient with their dish alignment and they give up and turn to DiSEqC 1.2 motor control to try to make up for their alignment errors. But, if you are using USALS, you cannot apply this technique. There is no option for it.

Using DiSEqC 1.2 is the cheater's method. It is a short cut that is not very accurate. It will get you by, but t is not truly accurate. Using USLS demands you to align the dish and motor accurately and USALS will not allow you to cheat. With USALS you must have the mechanical alignment of the dish perfect.

You will understand this eventually, just take some time and ponder it.

RADAR

 

[crackt]

Using DiSEqC 1.2 is the cheater's method. It is a short cut that is not very accurate. It will get you by, but t is not truly accurate. Using USLS demands you to align the dish and motor accurately and USALS will not allow you to cheat. With USALS you must have the mechanical alignment of the dish perfect.

You will understand this eventually, just take some time and ponder it.

RADAR

i think you should have said "... if using diseqc 1.2 as a cheater method....". it is common knowledge that most recievers dont use the liscensed usals algorithm and that diseqc 1.2 is the only truely accurate method for positioning a dish. ive read more than one thread about usals inconsistencies across the arc. it usually gets worse as the dish is further from south. id recommend using usals to locate a sat and then switch to diseqc 1.2 mode, tweak, save and continue using diseqc 1.2 for motor control.

crackt out,.

 

[AcWxRadar]

i think you should have said "... if using diseqc 1.2 as a cheater method....". it is common knowledge that most recievers dont use the liscensed usals algorithm and that diseqc 1.2 is the only truely accurate method for positioning a dish. ive read more than one thread about usals inconsistencies across the arc. it usually gets worse as the dish is further from south. id recommend using usals to locate a sat and then switch to diseqc 1.2 mode, tweak, save and continue using diseqc 1.2 for motor control.

crackt out,.

Crackt,

No, I said and wrote it just perfect. It is accurate and it is what it is. Also, it is incorrect to state that most receivers are not licensed to use USALS official algoithim. Every FTA receiver that I have purchased since 2003 (except one which was given to me) has been USALS aproved. I am sorry that so many disagree with me on this subject or that they just are uninformed or misinformed, but USALS is truly the best system to use. You must experience both with a perfectly aligned dish to appreciate the differences and advantages of USALS.

I don't intend to disagree with you or anyone on this subject just to put you out, but I will argue the point because of what I know and what I have experienced. USALS is the way to go and DiSEqC 1.2 is usually used to cut some corners off (but not always).

RADAR

 

[crackt]

i know youve read this radar but maybe the OP hasnt.

http://www.satelliteguys.us/free-air-fta-discussion/166471-usals-notebook-4.html

im not saying you cant use usals. im just saying the OP is already asking to tweak it somehow. ive aimed a few hh motors. i set them to use usals. but its for ease of use, not accuracy. i now use a modified 1m cm on a jack and dont even use usals presently. when i did have an hh running i tweaked it by modifying the sat degree but found i couldnt edit the location with the cs8100 i had. its alright to disagree, everyone has an opinion.

crackt out,.

 

[Larobpra]

USALS = useless!

That's just my experience with it.

YMMV

 

[AcWxRadar]

There are advantages and disadvantages to both systems here.

The disadvantage with DiSEqC 1.2 is that you have to set up (fine tune) each individual satellite which requires some time. If you ever have to reset your motor for some reason, you just cleared all those settings since these settings are stored in the motor's onboard memory. That means repeating all that work.

The disadvantage with USALS is that your dish and motor must be perfectly and precisely aligned. This can require a lot of time to get it right. This is usually where many stop short of their goal and switch to using DiSEqC 1.2. The other disadvantage is that there is no method to tweak the position if you desired to except to alter the orbital location of the satellite (i.e. 97.0° changed to 97.1°). Some receivers won't allow you to do this without deleting the entire satellite from the list and reentering it with the changed orbital degree.

The advantage of USALS is that when the dish and motor are perfectly and precisely aligned, USALS will drive to any satellite you enter into your list with 0.1° accuracy or better every time. Also, if you swap out your receiver or reset your motor, nothing changes since the physical alignment of the motor and dish are what are at the heart of USALS accuracy - along with entering your site's latitude and longitude coordinates the same. This is, of course, dependant upon the new receiver being truly USALS compliant. There are several which are not.

I know I harp on this subject often and with over zealous passion, but I truly believe that so many people are missing out on a really great opportunity here. So I keep being pro USALS until enough people try it and discover it first hand.

I have used and still do use both DiSEqC 1.2 and USALS motor positioning control. I have need for both, within the same system and setup.

One thing that I can tell you about USALS is that I cussed and I scratched my head and if I had a cat I would have kicked it. I gave up many times because I got so mad that I couldn't think straight. However, it really pays off in the end when you do get it right.

Now, knowing and understanding the errors that I made and the physical errors and limitations of some of the equipment and some of the errors that were introduced by inaccurate satellite position locations given on Lyngsat, I can manage to align a FTA, Ku band, motorized system using USALS within 15 minutes. (Actual installation of the hardware and scanning channels in requires extra time, of course).

I hope you understand that I am not disagreeing with anyone, but rather making a case for opening a new door.

RADAR

PS What RogerDuncan is stating in the OP is not accurate as there is no option to "step" the motor when using USALS. So, he is somehow confusing the two systems. You can only tweak the alignment by stepping the motor if you are using DiSEqC 1.2 In this case, he was asking the question "how many degrees" (or tenths of a degree) is each step. I don't think that this can be answered with any accuracy. This would vary between receiver models and some receivers have different settings for this as well. I think a person would have to calculate this for their own receiver. You would have to start on the peak of one satellite and count how many "clicks" you had to make to get to the peak of an adjacent satellite and then divide the number of clicks by the degrees between the satellites. Even this wouldn't be very accurate, but you might obtain a rough idea.

 

[rogerduncan100]

Interesting stuff here, thanks!

Radar, I heard somewhere that USALS is inaccurate in how far it turns (let's say from true south). Thus the sats at the extremes do not get aimed at exacly right. What is your comment about this?

PS: I don't think my Viewsat Max with SG2100 motor can even function in DiScEq.

rogerduncan100

 

[crackt]

Interesting stuff here, thanks!

Radar, I heard somewhere that USALS is inaccurate in how far it turns (let's say from true south). Thus the sats at the extremes do not get aimed at exacly right. What is your comment about this?

PS: I don't think my Viewsat Max with SG2100 motor can even function in DiScEq.

rogerduncan100

read the link i posted above.....

there are some scenarios where you cant tweak usals no matter what (ex. coolsat 8000/8100). you cant even add an orbital location using that reciever. diseqc 1.2 is also accurate to 1/16th of a degree or 0.0625. for ease of use tho, usals works fine enuff.

crackt out,.

 

[rogerduncan100]

Crackt, thanks for the link!

I had a feeling I needed to tilt the motor slightly upward and the dish slightly downward to track the Clark Belt better. I have been messing around with the geometry of cones and whatnot but this seems to be the chart that is the answer to what I was trying to accomplish. I can let the chart do the thinking for me!

You and Radar obviously disagree about the worth of USALS. Maybe it depends on the receiver and the USALS vesion.

 

[rogerduncan100]

I am finding the terminology very puzzling. I am sure different people mean different things when they use the same words. For example, the charts equate latitude and elevation angle. Others, such as myself think lattitude plus elevation angle equals 90.

What I want to know is how many tenths of a degree to change my motor axis from the earth's axis. Then after I point exactly at the hypothetical true south sat I will track the Clark Belt perfectly with my dish.

 

[greg47]

USALS set up correctly with a perfect aligned dish a new motor and peaked in correctly on your true south satellite will go to each satellite correctly. But you will find in time that the wear that happens inside the motor and in the gear reduction will eventually throw your position off. Also I have seen the position get thrown off by missed pulses inside the motor by any electrical problem, usually a surge or power out will cause them to be off. Sometimes the reciever gets confused by data recieved from the sat itself and it does a reset. I have seen it all happen, now you ask what I use ? USALS till I notice the wear then I switch to DiScEq.

 

[AcWxRadar]

Interesting stuff here, thanks!

Radar, I heard somewhere that USALS is inaccurate in how far it turns (let's say from true south). Thus the sats at the extremes do not get aimed at exacly right. What is your comment about this?

PS: I don't think my Viewsat Max with SG2100 motor can even function in DiScEq.

rogerduncan100

Roger,

A true USALS compatible receiver is extremely accurate, down to a tenth of a degree or better. However, the USALS program is limited in its maximum east or west travel calculation.

USALS is nothing more than a math program that utilizes your site coordinates (latitude and longitude) and the orbital degree of the satellite to determine where to position the dish.
With a properly aligned dish and motor, USALS uses this information to calculate the accurate position that the motor should drive to. Once you have menchanically or physically calibrated one satellite, usually your true south satellite, the USALS program knows where all satellites are across the horizon.

It is not magic, and it is nothing new. It is just a math program that is beneficial to use. You can drive your dish to any satellite position using USALS and be 0.01 degrees accurate in the position. However, this accuracy is only applicable for as much as your mechanical accuracy of the dish and motor alignment are. The math program of USALS itself is accurate down to 0.01 degree, but your mechanical alignment of the dish and motor are limited to less accuracy than this. Since you cannot read this level of accuracy from any of your dish or motor scales, you have to use the signal from the satellite to align it.

Therefore, if you have calibrated your dish and motor to align at your true south satellite and you apply USALS, then all other satellite positions are known, with extreme accuracy - as accurate as you have aligned your dish and motor.

With my system, I can enter any satellite orbital position and tell it to use USALS to locate any satellite and the H-H motor drives right there. I don't have to use DiSEqC 1.2 motor control to "tweak" it in. If the given orbital position for the sat is accurate, then the system aligns itself to that position nearly perfectly. Using DiSEqC 1.2 motor control I usually cannot position the motor any better.

There is a limitation of USALS, however. I have found that all receivers and motors using USALS quit at approximately +/- 59° from your site's longitude position. Any satellite further than 59° east or west from your home location requires you to resort to DiSEqC 1.2 to locate the sat's position. This is not too much trouble, but you need to know of it in advance.

What you heard or read about the inaccuracies of USALS is a myth. It is extremely accurate all the way from the west most to the east most limit of its program. Beyond these limits (+/-59 or so degrees) it does not stop being accurate, it just stops operating, period.

You will not understand this concept fully untill you have aligned your dish and motor perfectly and tried it all out for yourself. If you are used to using DiSeqC 1.2 motor control, you may have a hard time getting used to USALS, because or since you have the concept of DiSEqC 1.2 control ingrained in your mind.

RADAR

 

[AcWxRadar]

Crackt, thanks for the link!

I had a feeling I needed to tilt the motor slightly upward and the dish slightly downward to track the Clark Belt better. I have been messing around with the geometry of cones and whatnot but this seems to be the chart that is the answer to what I was trying to accomplish. I can let the chart do the thinking for me!

You and Radar obviously disagree about the worth of USALS. Maybe it depends on the receiver and the USALS vesion.

Roger,

There is no other version of USALS. USALS is USALS and there is nothing else. That is like saying that there is another way to add 2 and 2 together. There is only one way. Add 2 and 2 and you get 4. There is no other way to do it.

USALS is nothing more than a math program like this. But, it is copyrighted or owned like Einstien's theory of relativity. No FTA satellite receiver can sport the USALS LOGO and endorsement and lable unless they submit their reciever to the USALS lab and it passes the criteria set forth for USALS.

I am finding the terminology very puzzling. I am sure different people mean different things when they use the same words. For example, the charts equate latitude and elevation angle. Others, such as myself think lattitude plus elevation angle equals 90.

What I want to know is how many tenths of a degree to change my motor axis from the earth's axis. Then after I point exactly at the hypothetical true south sat I will track the Clark Belt perfectly with my dish.

Forget the terminology for now, Roger. That is immaterial for what you want to do.

You need to know your site's latitude and longitude. Then you need to know the orbital position of your truest or closest southern satellite. The satellite which has an orbital location or slot that has the nearest degree location to your site's longitude.

i.e. My location is NW of Omaha, NE. My actual coordinates are 41.6°N and 96.4°W. Therefore my closest or nearest TRUE SOUTH satellite is Galaxy 19 at 97°W.

Set (align) your dish and motor as close as you possibly can for your nearest TRUE SOUTH satellite.

RADAR