Motorized KU band issue

[ftaseek]

Hi All,
I have Amiko A3 with 100cm dish, Universal LNB & Moteck SG-2100.
Before I installed motor my fixed setup was fine and I was getting Galaxy 19 with many channels.
After installing motor doing the setups (Lat=40.8, Long=74.2), I saw the the satellite closest to my true south is 75W KU Star One C3 (12427/10500/H), aimed at it and got some quality sig on it. But the signal was like some mexican channels (AMX, mexiquense, etc) which I think was actually satellite 77W (QuetzSat1), found by googling AMX and mexiquense. Then I moved the dish to 97W to get Galaxy 19. I got some signal here too (SBN, NHK World, and other chinese channels) and they look like coming from SES-1 101W.
Help pls, what am I doing wrong and how can I fix it? I attached some screen shots.

 

[cyberham]

There seem to be no active transponders on 75W. 77W has circular transponders that normally require you to have a circular LNB. But if you can receive signals from 77W, then use it. A strong transponder on 77W is 12276 R 10500. Use your receiver to motor to 77W. Then go outside and physically move your whole motor/dish assembly to peak your received signal. Also adjust the motor elevation adjustment to peak your signal.

If you then motor to 97W, and check the 12152 H 20000 transponder, you should have a good signal. If not, only adjust the dish declination (dish elevation, NOT motor elevation) to maximize your signal. Check other satellites to the west and do the same.

Then go back to 77W. If that signal has gone down, only adjust the motor / dish assembly azimuth to maximize the signal.

Do the above two paragraphs multiple times. Back and forth checking each end of the arc.

If you do this right, you will be peaked on the arc.

By the way, those images above are from 101W and probably 77W.

 

[ftaseek]

Thanks Cyberham, I'll check your points and update here

 

[ftaseek]

I couldn't find 77W in my A3 list, closest one was 78W, tried that for an hour but couldn't get any signal quality, even though meter was beeping a lot. Is it possible the list in A3 may not be correct? As I was seeing 77W on A3's setting of 75W? I'll try more tomorrow.

 

[cyberham]

I don't know the A3 but, if 77W isn't listed, can you add it? If not, 78W would be fine too if you can receive any transponders from it. It's not too critical which satellite you start with. But it should be your most southerly satellite from which you can receive a signal for best results.

 

[a33]

1. Let's first check: Can your receiver give a GotoZero (or GotoReference) command? Does the motor then go to exactly the Zero-mark of the tube?

2. I assume the pole is plumb east/west-wise, and you set the motor and dish angles correctly?

3. Now let's try to use a satellite you already receive, to align the setup to due south/ highest point of the arc.

I saw the the satellite closest to my true south is 75W KU Star One C3 (12427/10500/H), aimed at it and got some quality sig on it. But the signal was like some mexican channels (AMX, mexiquense, etc) which I think was actually satellite 77W (QuetzSat1),

I assume you used USALS, to move to the satellite defined at 75W (or 74.2W) in your receiver?
In that case check that you still receive the 77W channels. (In case that you get a clear improvement by changing the motor elevation a bit, do that. If the signal is strong enough already, that is not necessary.)
Now define the channels you receive as 77W (instead of 75W or 74.2W) in your receiver, and goto that satellite (with USALS). You'll then lose reception, when the motor moves.
Then rotate the whole setup around the pole, and find your channels again. (In your case it would be rotating a bit to the left: Your due south was aimed at 77W, but should be at 74.2W.)
Does this bring the 77W channels back?

Please give feedback on the above three points.

Greetz,
A33

 

[arlo]

Can I ask w/o hijacking?
If you opt to used diseq over usals in a receiver how is the motor manually activated and moved?
I'm familiar with the ASC1, vbox movers for linear actuators with manual controls in the mover and stored pos./sat.
And are encoder counts shown in the receiver?
Once you get a sat. reference in diseqc in encoder counts. Lets say 97W is 1200.
Are the same count references shown in the usals screen once you switch back?
I'm close to getting a usals mount.

 

[cyberham]

On the Edision, there is a screen that allows you to manually move the dish using diseqc commands. When you get the signal peaked, then you can save the position of the motor either in the motor or on your receiver. There is no counter displayed. Whereas when using USALS, the dish moves automatically to the position calculated by the USALS function based on your lat/long coordinates. In this mode, you can still manually move the dish but you can't save the new position.

So I find satellites using USALS, but then manually move the dish to peak and store that setting. Once I find all satellites, then my dish is normally in diseqc mode, not USALS.

 

[a33]

So I find satellites using USALS, but then manually move the dish to peak and store that setting. Once I find all satellites, then my dish is normally in diseqc mode, not USALS.

To add:
USALS calculation itself (Goto-X) is very accurate (when you have your zero exactly at due south/north).

It's things like backlash in the motor(tube), that make a diseqc 1.2 Goto-Nn setting sometimes needed, I would think.

 

[Jim S.]

There's no way to see the encoder counts. The receiver sends a command to the motor to store the current position in a numbered memory slot in the motor, and you tell the receiver which slot to use for each satellite.

 

[cyberham]

To add:
USALS calculation itself (Goto-X) is very accurate (when you have your zero exactly at due south/north).

It's things like backlash in the motor(tube), that make a diseqc 1.2 Goto-Nn setting sometimes needed, I would think.

Yes USALS is accurate. My issue is either my old motor and/or my temporary tripod. So each time the dish returns to a given satellite, it could be a bump or two off. I've learned to live with it since it's reliable otherwise. Someday, a new motor and pipe in concrete will solve all and then I can live in USALS.

 

[ftaseek]

1. Let's first check: Can your receiver give a GotoZero (or GotoReference) command? Does the motor then go to exactly the Zero-mark of the tube?

2. I assume the pole is plumb east/west-wise, and you set the motor and dish angles correctly?

3. Now let's try to use a satellite you already receive, to align the setup to due south/ highest point of the arc.

I assume you used USALS, to move to the satellite defined at 75W (or 74.2W) in your receiver?
In that case check that you still receive the 77W channels. (In case that you get a clear improvement by changing the motor elevation a bit, do that. If the signal is strong enough already, that is not necessary.)
Now define the channels you receive as 77W (instead of 75W or 74.2W) in your receiver, and goto that satellite (with USALS). You'll then lose reception, when the motor moves.
Then rotate the whole setup around the pole, and find your channels again. (In your case it would be rotating a bit to the left: Your due south was aimed at 77W, but should be at 74.2W.)
Does this bring the 77W channels back?

Please give feedback on the above three points.

Greetz,
A33

Thanks A33, I'll check these points. I'm sure the pole is plumb. I have to see how can I redefine the satellites in A3. I'll let you know of the findings.

 

[ftaseek]

Good news, it went to zero ok. I redefined 75W to 77W and did as you said. I got channels back on 77W. Motored to 97W and got about 140 channels. Then I tried Galaxy 16 but got only 10 channels, the SQ was a little low 40-45. I'll try some more satellites tomorrow.
Thanks very much for your tips.
This Forum Rocks!

 

[a33]

So, your due south is (about) OK now. Nice!

Did you check that while motor is on zero, the dish is exactly in line with the motor, and the LNB(arm) is exactly in line with the dish direction?

So it is time for further motor setup finetuning checks.
I usually use the 4 pictures as here:

Ustwianie obrotnicy - Strona 7 - Forum TV-SAT

Cześć,Dotychczas ustawiłem 2 obrotnice, ale zawsze jakoś mi się udawało. Na dniach będę montować obrotnice rodzicom i chciałbym, aby to poszło w mi..

satclub.pl

(Direct view of the 4 pictures: https://satclub.pl/download/file.php?id=135126&mode=view )

When you find a situation as in C or D, first solve that (finetuning further the due south setting)!
Note: the lower arrow means correction-direction for motor on pole, the upper arrow means correction-direction of dish on motor tube.

After that, do the corrections for A and B.
And then check again, if a correction C or D is necessary,
and after that again A/B, ...
(repeated procedure, till you are satisfied).

NB The E and W indications in the pictures are east and west, as seen from the northern hemisphere. For the southern hemisphere, they must be swapped, but the pictured finetuning solutions are still valid.


By the way. If you must do much A/B corrections, you might want to set the motor elevation an dish declination from scratch, again?
I'd then use the so-called modified motor angles. For your location: motor elevation angle about 48.6 degrees (modified latitude 41.4 degrees), dish declination offset angle about 5.7 degrees (so dish elevation scale reading about 30 - 5.7 = 24.3 degrees, for SG2100).

greetz,
A33

 

[ftaseek]

Thanks A33, I'll see what I can do. Again thanks for all your, cyberham's and everyone's help.
I don't understand what are we doing in C & D pics.

 

[ftaseek]

I understand C & D now but how do I know which situation do I have? A, B, C or D?

 

[a33]

I understand C & D now but how do I know which situation do I have? A, B, C or D?

By doing what is called in some (foreign) forums: "the finger-test".
That means that (assuming that you are more or less aimed properly at the arc, at about due south) you have to check at your 'extreme' satellites (far away from due south), whether by gently pushing/pulling the dish a bit upwards or downwards, the reception of that extreme satellite improves.

So for instance go to a sat 40 degrees west of due south, and check if gently pushing/pulling the dish a bit upwards or downwards improves the reception.
Do the same at a sat 40 degrees east.
Then conclude which of the 4 situations you have. (Or if all is perfect, already.)

When you don't have reception (yet) at 40 west/east from due south, because of improper motor angles, take the 'last' extreme satellite that you can receive. And check, what pushing/pulling improves reception.
When you've improved your motor angles based on that test, your next test might be done with more extreme satellites.

I normally do the gentle pushing at top and pulling at bottom of the dish (and vice versa) simultaneously. With a very big dish, this might be impossible . Note: do this pushing/pulling with the dish, not with the LNB arm!

In your case, C and D should hardly be a problem anymore, because you've aligned to due south with the USALS function.
Otherwise, the reason why you have to 'solve' C and D first, is because for A and B corrections you need a "symmetrical" improvement, left and right of due south. I have no idea why they put C and D after A and B, in the diagrams.

Does this make things clearer?

Greetz,
A33

 

[ftaseek]

A lot clearer, I couldn't do any thing yesterday or today because of rain.
Thanks A33

 

[ftaseek]

Finally got a break from rain yesterday, checked after work. Tried to do some changes but it got more messed up. Have to try on weekend when I have more time as days are getting shorter.

 

[a33]

Could you determine if you had a situation A, B, C or D?