Bad Luck, No Luck, & Frustrated! Advice, Please?

[radiobob]

I am new to the world of FTA sats, but as a broadcast engineer and ham operator for over 35 years, am absolutely no stranger to electronics. I've been battling this installation for almost a month and am frustrated as heck with the results I'm getting. Here's my setup:

Winegard 76cm dish, Fortec Star 0.3 dB NF LNBf, SG-2100 motor, Traxis 2550 receiver.

The dish is mounted about 12-15 feet up a 55 foot tower; the tower and the mount are completely plumb as verified with both an inclinometer and a bubble level. Mounting was done exactly per SG-2100 manual and installation advice on the Sadoun website. I'm at 30 deg N, so motor mount was set accordingly and dish declination set at 25 deg per instructions. A conventional satellite finder meter was used to peak signal to the nth degree.

Due south was computed by magnetic compass corrected for deviation from true (at my location only 0.5 degree), and verified by (a) GPS, and (b) checking direction at exactly local noon (computed from U.S. gov't. info).

The dish has a blue-sky view of the southern horizon with virtually no obstructions.

Feedline is approximately 30 feet of premium quality RG-6.

Results: Reception of ONLY 3ABN (English & Spanish) and KUIL, Beaumont on AMC4. No other signals on AMC 4 and NO OTHER SIGNALS from any other satellites despite east-to-west arc sweeps and careful attention to all settings--transponder freqs., data rates, LO freq., etc., etc.

I tested the receiver on a large (3 meter) dish at a TV station for which I'm doing consulting and it DID work on IA5. I've tried a different LNB, changed the feedline, and checked and re-checked my installation.

Could it be that my receiver is just deaf?

My thanks to anyone for any advice and the Sadoun folks for their excellent tech support pages.

[pmb1010]

appears you have some technical background, and seem to have grasp on what needs to be set, etc.

One thing I'd suggest, is remove the motor and try to aim the dish, alone to a few of the other sats in question, especially IA5 where you get it on a much larger dish, and not this one. That will tell you if the reciever is being fussy or not. Take the motor out of the picture. That will also give you a good inidcation of how "good" your scale is on the dish. Others report way different settings used, to calculated values.

You've got some components I've never worked with, but the basic premis is the same.

Please post back your results.

[wejones]

Originally Posted by radiobob

........
Results: Reception of ONLY 3ABN (English & Spanish) and KUIL, Beaumont on AMC4. No other signals on AMC 4 and NO OTHER SIGNALS from any other satellites despite east-to-west arc sweeps and careful attention to all settings--transponder freqs., data rates, LO freq., etc., etc.

I tested the receiver on a large (3 meter) dish at a TV station for which I'm doing consulting and it DID work on IA5. I've tried a different LNB, changed the feedline, and checked and re-checked my installation.

Could it be that my receiver is just deaf?

My thanks to anyone for any advice and the Sadoun folks for their excellent tech support pages.

Since your receiver worked on a couple satellited, I don't think the problem is your receiver, although it MAY be that the built in transponders in your receiver's memory are not current. Ie if your receiver is looking for a transponder that doesn't exist, it won't be able to find it, so check Lyngsat, and make sure that the signals your receiver is looking for are in fact active. My other question would be, is the AMC4 sat that you had some sucess with, your true south satellite? If not, I'd advise working on the true sout sat first. I'd assume that it was, if you were following instructions, however that sat being your true south sat does NOT seem possible if your 0.5 deg magnetic deviation and or the 5 deg declination angle you seem to be using are correct. Something isn't right here, either the true south, the magnetic deviation or the declination has to be wrong.... I think.... But assuming, I'm confused, and that it IS your true south sat, I'm curious what procedure you used to tune it it? Ie did you set the motor scale on your latitude, then adjusted the dish adjustment until you got a signal? If so, how far from the settings indicated in the instructions did you deviate before getting the signal? What is your latitude/longitude? I don't have the same motor/dish you have, but the installation instructions, particularly the angle that you set the dish setting (I think it says 30 deg minus declination at the Sadoun site), is dependent on the offset angle of the motor shaft, and I've seen that some of these motors "may" come with different offset angles, so it's possible that you are following the directions for a different motor. If you can estimate the offset angle of the shaft where the dish attaches to the motor vs the rotation axis inside the motor, then you can verify that you are using the proper equation to set the dish angle. However if you found your south satellite by first setting the motor angle to your latitude, then searched for the sat via adjusting the dish angle, then you don't really have to worry about the calculation. But I'm thinking that maybe you weren't actually looking at your south satellite.
Bottom line is that you must first find your true south satellite, without changing the motor angle much from your latitude settings before going off trying to locate other satellites.

[briand]

Hmm. Yes, I would say it's probably a dish-pointing problem. It's sometimes a real bear to get everything set as it should be. For instance, it is possible to have a (nearly) infinite combination of values for the elevation on the motor and the elevation on the dish when pointing directly at your due south satellite -- as long as the two add up to the elevation for that satellite, you'll get great reception... but only one (ideal) pair of settings is correct to accurately track the clark belt and get excellent reception on all satellites.

If you were to imagine two hyperbolas (hyperbolae?) of widely differing slope meeting at the apex, this would help you visualize what I'm saying. As you "flatten out" the steeper one, more and more points (satellites) centered around the apex (your true south satellite) become congruent between the two curves. At one precise setting, the two curves become congruent throughout the arc -- this is the setting you need to strive to attain. There's another explanation of this somewhere on this site, complete with pictures that demonstrate the same thing, but I cannot locate it at this time...

And, of course, on top of that, it appears that some manufacturer's alignment marks (on dishes and motors) is less than ideal... so use those marks as "rough guides"... they're usually within 4-5 degrees of correct (but, as you know, 4 or 5 degrees is a -lot- when pointing at something as far away as a satellite!)

Perservere, radiobob... and do let us know how you progress. I'm confident you'll get it eventually.

... 73 de AI4AI

[elgemcdlf]

Ok in concept declination (dish elevation) basically sets the arc shape. The higher the angle the higher the peak in the center and the closer the ends are to each other. Elevation (motor elevation) sets the location in the sky. Start with what you have. Move sat by sat to the west until you have no more signal. Go to the sat that last had signal. Now gently push up on the dish then pull down. Signal raise or lower? If yes to either note what it did. Now do the same to the east. If you have opposite reactions you are not on true south correctly. I do not care what GPS says

Move the assembly (rotate on the pole) in the direction of the side that read higher when pushing up. Not much as you most likely are close. Repeat until there is a lower reading when doing both pushing up and pulling down. You are now centered on true south. Well wait a minute you wish to be equal distance from center when doing this. So if you moved 15 degrees west you need to be 15 degrees east for the same test.

Ok repeak your true south sat WITHOUT rotating the assembly on the mast. Using only dish or motor elevation settings. now let's see how much of the arc we are tracking. Go sat by sat and write down readings. You should see a pattern which will tell you if your arc is to high in the sky or low. Or if the arc is too flat or curved. Adjust accordingly. You need a very sensitive touch here. 1/8" movement can loose you signal. I suggest moving 1/2 degree and rechecking for effect.

Let me know how it goes

[rainman]

also check out this site should help on alignment. www.geo-orbit.org

[wejones]

Originally Posted by elgemcdlf

Ok in concept declination (dish elevation) basically sets the arc shape. The higher the angle the higher the peak in the center and the closer the ends are to each other. Elevation (motor elevation) sets the location in the sky. Start with what you have. Move sat by sat to the west until you have no more signal. Go to the sat that last had signal. Now gently push up on the dish then pull down. Signal raise or lower? If yes to either note what it did. Now do the same to the east. If you have opposite reactions you are not on true south correctly. I do not care what GPS says

Move the assembly (rotate on the pole) in the direction of the side that read higher when pushing up. Not much as you most likely are close. Repeat until there is a lower reading when doing both pushing up and pulling down. You are now centered on true south. Well wait a minute you wish to be equal distance from center when doing this. So if you moved 15 degrees west you need to be 15 degrees east for the same test.

Ok repeak your true south sat WITHOUT rotating the assembly on the mast. Using only dish or motor elevation settings. now let's see how much of the arc we are tracking. Go sat by sat and write down readings. You should see a pattern which will tell you if your arc is to high in the sky or low. Or if the arc is too flat or curved. Adjust accordingly. You need a very sensitive touch here. 1/8" movement can loose you signal. I suggest moving 1/2 degree and rechecking for effect.

Let me know how it goes

I'm not saying that the above won't work, but it is WAY more complicated than it needs to be.
First of all, assuming that you can set either the motor angle or the declination angle correctly, then once you peak on your southern sat, there is really no need to ever go back and re-adjust that. Of course Briand's comment that there is an infinite number of combinations of motor angle and declination that will appear to give you results on the southern sat, if you are extra careful on this, you will probably be close enough never to have to touch it again. THe only exception might be if you were WAY off on your compass heading to the south, or if your pole isn't plumb.

On my dish, I can very accurately set the declination, so I set that first, then peak the southern sat using the motor angle, however most small dish owners tend to feel that they can set the motor angle more accurately, so they tend to set that, and peak on the south sat using the declination (dish angle). Whichever you think is more accurate. But once you set this, I'd recommend leaving it alone.

Then, as is suggested above, you move the dish to the sat most to the west or east, ie if you are in the eastern US, go to the west, and if you are in the western US, go to the east. You can really complete your alignment there, ie to the east or west, without ever going back to the south sat, or to a sat to the other side of south. I'd suggest doing what is described above, ie turning the mount on the pole slightly toward the direction indicated by the pushing up on the dish test. However what I do, is then scan back and forth through this sat using the motor, and again peak on that same sat, and repeat the push up/down test, and again rotate slightly, again away from south if you need to push up, and back toward south if you need to pull down. At this point, you can usually move your dish using the motor, to the furthest east or west sat viewable from your location, and repeat this process, fine tuning with even smaller changes, again rotating on the pole away from south if you need to push up to improve the signal, and back toward south if you need to pull down. Once you've done this, 99% of the time you are done.
The theory for all the above, is that when aimed at the southernmost sat, moving the mount on the pole doesn't have much affect, unless you are WAY off. And conversly, when aimed at a sat near the eastern or western horizon, changes to the motor angle and declination have little effect, so there is really no need to go back and forth between south, west east, because these adjustments are NOT interactive, but rather are sort of orthogonal adjustments that don't affect each other. Set motor angle/declination on the south sat, and mount on pole with an east or west sat, and you are done. However, the key to what I've said above, is that the rotate on the pole adjustment needs to be peaked using the motor, because when you rotate on the pole, you aren't turning the dish toward the satellite, but instead toward the arc, so you have to run the motor to bring the dish along the arc toward the sat. When I do this rotate the mount on the pole adjustment, more often than not, the signal is worse after I make the adjustment, however that is expected, and when I run the motor to re-peak the sat, the result is better than before the adjustment. I hope that's clear, but I've probably confused things more than before. :-(

[radiobob]

My thanks to all for the excellent collection of well-thought-out and well-presented suggestions.

First up...I got pretty much the same results before I installed the motor; I'd set azimuth (again, at my location magnetic is only 0.5 degree off true) and elevation then gently adjust each arc for peak reading on the satellite finder meter.

Bill, I had, indeed, checked TP freqs. against Lyngsat and FTAList; I've found quite a few that were off from those preprogrammed into the box.

AMC4 is not my "true south satellite"; it is just the one that I stumbled onto that works. Briand, I considered that I just lucked into the intersection of two parabalos...er...parabolae...uh curves! Yes, it is conceivable that a blind squirrel just happened to find some nuts! (Although I still wonder why I can pick up only 3 channels on AMC4...unless they're the only ones active).

My true south satellite is Galaxy 11 (@ 181.8 degrees) from my location (30N, 90W), but so far have not gotten anything discernible from that bird. I will reset and re-try again just to be triple sure. (Remember, too, that I really, really know where 180 degrees is 'cuz even if my compass is wacky and my GPS fried, the sun at local noon (was 1:01 CDT a few days ago) doesn't lie!

With regard to the procedure involving moving the motor (I can't move the pole as it is one leg of a 55 foot tower!), the nature of how the motor is mounted limits how much westerly movement I can accomplish this way; while the motor can rotate the dish through the full arc, I can't move the motor a full 180 degrees without bumping into one of the other tower legs. I will reconsider how it is mounted, but I don't know what success I'll have in that department.

Once again, I am deeply appreciative of all your kind responses. I have posted appeals on other forums (fora?) and gotten no or less-than-useful responses. I am impressed! THANK YOU!

More to follow...

Bob
de K5IQ

[radiobob]

Further to above...

I just got off the ladder (man, is it hot here!) and re-re-peaked sat finder for Gxy11 (181.8 az/55.1 el from my location), but still no joy. Signal stength indicator on the receiver barely moves and never shows quality reading in a scan across all transponders.

I could sure use one of those Sathawks or Birddogs or even a $10K spectrum analyzer!

[pmb1010]

Cheap satellite finders are junk.
I suggest you use the receiver AT the dish with some short cables, to locate the sats.
Use the quality indicator of the receiver to line up the dish.
I know you are on a tower, but find a way with a platform of some kind hanging of the rungs to put your receiver and a small TV...

KUIL Fox on AMC4 should PEG your quality reception in TX/LA area.
I'm in NY and it's 95% quality here. BIG signal.
11708V

[radiobob]

Originally Posted by pmb1010

KUIL Fox on AMC4 should PEG your quality reception in TX/LA area. I'm in NY and it's 95% quality here. BIG signal.
11708V

Yeah...and yet, I'm getting 29% signal and 49-50% quality reading! And, let's face it...if that's what I'm getting from KUIL after peaking it to the max, no wonder nothin' else is readable.

And, you're right, cheapie satellite meters are junk, but at least I'm able to detect subtle signal changes easier with the analog meter than the bar graph display on the receiver. That said, there seems to be enough ambient RF around that no matter which way the dish is pointed, the sat finder will indicate something!

So, tomorrow I'll haul the receiver up the ladder I've got parked next to the tower and experiment around. I'm not optimistic, though, that my results will be any different. I'll let you know...

Once again, thanks a whole bunch!

[pmb1010]

wow.
somethings not right.

Any way you can take a JPG of your dish for us to see?

Try to pull or push your LNB in it's holder closer or further from the dish's focal point for a change?

Bad connector? (good short cables with the receiver near the dish will elimate that one).

[radiobob]

Yep...that's "do-able". Tomorrow I'll take some snaps; I'd LOVE to find out that I've done something stupid!

Haven't tried sliding the LNBf in and out...that's a good suggestion, though. I'll also try that in the a.m.

Again...t h a n k s!

[pmb1010]

Funny you should mention spectrum analyzer... I just bought a used Tektronic 2712. I'm also a ham, spend some time tinkering helping the local clubs with their GE repeaters. My Moto service monitor only has scope, so this SA should be fun toy to tinker with. Will have to investigate if it will read these LNB signals or not. Interesting idea.

As far as HF, you'll find me at lower band edges, .025 or lower. All CW.
Mostly during contests. Medium speed op, 30-40wpm.