Fooling My Motor

[Trip]

Good evening,

Over the weekend, having knocked my dish out of alignment earlier in the week, I decided to fidget with it until I got it to track better than it was. (I'd previously eye-balled it and then gotten 125W peaked, so that it fell off around 91W.) Anyway, after much negotiating on Saturday and Sunday, I got it to track successfully! I think that might be the first time I've ever gotten a dish to track with high signal from one end to the other. (72W to 125W.)

One problem, though. While it does track the arc, it doesn't stay consistent with the numbers shown. For example, with my coordinates set right in USALS, I have to choose "84W" to get 83W to a high signal level. If I move myself one whole degree in the USALS settings (from -77 to -76), it matches perfectly at 72W, and is only slightly off at 83W. It's not off as much at the western end of the arc at my actual location, but still does need manual adjustment, maybe less than half a degree worth.

So my question is, how can I fool the motor into tracking as I want? I'm guessing I have to screw with the lat/lon and figure out where it needs to be to work properly. Is there any relatively easy way to do that?

Thanks!

- Trip

 

[Anole]

Doesn't sound like its tracking at all.

What motor? (how old)?
What receiver? (latest firmware)?
Pole plumb?

Did you tell the motor to move to your TS bird before initial alignment?D

Did you use the correct side of the motor bracket to set motor elevation?
Is the bracket square to the pole?

 

[Trip]

It tracks properly because the signal levels stay consistently high across the arc, factoring in the adjustments noted in my initial message. This includes a 100% signal on NBC on 72W, and OETA at 61% on 125W, which is within 2 points of the highest I've ever seen OETA. I've NEVER had this kind of success before, and I'm afraid to so much as breathe on it now for fear of losing my alignment.

To your questions.

I think it's the 9120. I got it from Galaxy Marketing in Atlanta around 1/1/12.
TeVii S660 USB receiver, with newest driver. Using Prog Finder to move the dish, Crazy Scan to blind scan, and TSReader to view programming.
Yes. I replumbed it (is replumbed a word?) after I attached the dish and motor to be sure it didn't tilt when I added that weight to it.

TS bird? If you mean the one over my longitude, there isn't one (77W longitude is where I am now, roughly), so I used the slide on 85W and 12036 on 125W to do my aiming.

Yes and yes, so far as I know.

- Trip

 

[gpflepsen]

Run it down to 30W, if you have sky there. If you have good signal there, that's damn good for alignment.

 

[gpflepsen]

Forgot to add, I have a few orbitals adjusted via longitude to make them peak better. That's always a viable option if it works.

 

[Jim S.]

Run it down to 30W, if you have sky there. If you have good signal there, that's damn good for alignment.

This. From 77W, 72-125 is only half the arc, really. 15W is even an easy target if your line of sight is clear, and there used to be a live low-band transponder way down on 8W. (I'm not sure if it's still there due to leaves on the trees.)

 

[markbone100]

30W is one I cannot get due to LOS, but everything else tracks fine. I had to adjust latitude a few times though due to an accidnetal bump with the mower and moving it back into place

 

[Trip]

I tried to run it over to 30W but I don't think I have line of sight there. I did see things in Crazy Scan on 61W, though. Not sure there's much on Ku between 61 and 30 (that the US can see, at least) that I can use to see where it falls off.

- Trip

 

[Jim S.]

Not really, no. Two low-band TV channels and some data transponders on 45W, and data transponders and rare (and weak) feeds on 37.6W. Oh, and a bunch of encrypted (and one unencrypted sometimes) low-band channels on 50W.

 

[Blindowl1234]

Most of us are lucky to get 72W to 125W lol...I dream of 30W

 

[northgeorgia]

Not really, no. Two low-band TV channels and some data transponders on 45W, and data transponders and rare (and weak) feeds on 37.6W. Oh, and a bunch of encrypted (and one unencrypted sometimes) low-band channels on 50W.

Just to add: Bolivia sometimes uses 45W low band and high band for national feeds (president/vice president on location). Also, 53W has the one religious channel with secondary audio, but on the radio side, from time to time you will find surprises!

 

[Jim S.]

I'm out of the footprint for 53W. Alexandria looks like it might be out of it too, but I'm not sure.

 

[Trip]

So I'm still looking for thoughts on how to fool my motor into going to the right spot when I tell it to go to a particular satellite. I'm still thinking using incorrect coordinates in USALS, but not sure where to go. Any ideas?

- Trip

 

[gpflepsen]

IF all your sats are similarly shifted, either physically adjust your dish or adjust your USALS longitude to compensate. You can individually tweak a location for a sat if there are a few needing adjustment. If you need to do more than that, go back to aligning the dish from the start.

 

[Tron]

I would physically adjust the motor and dish assembly correctly, rather than fool the motor with compensated coordinates. It will track the arc much better in the long run.

 

[Trip]

I'm afraid to touch the dish, now that it basically tracks. If I wasn't trying to use USALS, I would say it's done.

I guess I could look at non-USALS dish pointing...

- Trip

 

[gpflepsen]

Does it track the arc? If yes then it is physically aligned.

If it is in alignment, are all the sats offset more or less the same? If so, the motor is probably not referencing TDC for the 0 position. reset the motor at TDC.

Just another possibility....

 

[Cham]

maybe try changing the latutude up or down 10 degrees (in the software, not the physical adjustment) and see what that does. Some have reported doing this in the past.

 

[cyberham]

...I'm still thinking using incorrect coordinates in USALS...

Edit your USALS longitude coordinate by a small increment in either direction. I change mine in 0.1 or 0.2 degree increments at a time. If signal quality increases on your reference satellite as you edit this value, then keep changing it in the same direction. If signal quality decreases, increment the value in the opposite direction. When you find the peak signal quality, you're done.

If your system is basically installed correctly, and you have USALS configured for each satellite, the above procedure should place your dish at the best location for almost every satellite. I find on the edges of the arc, you may get better results if you don't use USALS and use diseqc commands instead for the very best peak in quality reading.

Right now, I have my USALS longitude value set 0.9 degrees off the "corrrect" longitude value. Doing this is a lot simpler than trying to tweak the dish so you can enter your exactly correct longitude value.

 

[Anole]

It's gotta be something

Do you have any STBs you could try generating USALS commands with?
Others don't find this sort of problem, so I have to wonder:
- is it some mechanical alignment problem?
- or an error in generating the USALS commands?
- well, I suppose it could be a wonky motor, too.

Edit: I thought of another possibility...
- error entering initial GPS location
possibly converting between degrees/minutes/seconds and decimal degrees?
(a simple English to Metric error was responsible for a crashed probe on Mars)
.