Out with the bad - My Fifth BUD

[turbosat]

Hey linuxman, the bible (satellite installation and tuning manual) says
too little declination, if you have to push down on the ends to get better signal -your arc is too flat....
quote, I say, "Most tracking problems are associated with an incorrect
north/south orientation. However, if declination angle has not been properly
adjusted, tracking will also be incorrect. Lining up an antenna with the satellite arc is simply a matter of lining up two half circles, that in which the satellites are located, and that scanned by the polar mount."

 

[linuxman]

Thanks Turbosat,

I studied the picture below, and I think it is too little declination too.

Here is the picture:



As Anole said, I'll try one, and if that doesn't work, I try it the other way.

Edit: After looking at the picture again, the picture could very easily be interpreted as to much declination.

Fred

 

[tvropro]

Hey Fred,

Glad to see the Unimesh is working out. Looks like a few more turns of the wrench and you'll be there

 

[linuxman]

Hey tvropro,

Just a few more turns in the right direction and it will be done.

Hopefully today it will be finished.

The original setting on the Focal Length of 48-1/4" gave some outstanding C-Band numbers. The highest I have ever seen on the Pansat including the Birdview. I had 65% SQ on the California Channel on G15 133W (that is an extremely weak C-Band channel) and 100% on the CW on G11 91W.

After making some adjustments for Ku, those numbers have come down a little, but are still great. If I can just get the Ku to line up, I'll be a happy camper.

Fred

 

[linuxman]

Alright,

Here is where I am at, and I will tell you how I got here.

First off, tried to add a little declination, (bring dish forward) and compensate with equal elevation adjustment. That actually hurt the signal on the ends, so I took out what I added and took out a little extra (push dish backward at top) with equal elevation adjustment.

Got a much better Ku signal at the top with 65% on 91W 12060 V.

A little improvement on both ends, but not much. Pushed the dish backwards a little more, no help at the top, but a little bit more on the ends. Tried the push up and down on both ends, and no improvement.

So I thought, now that I have the dec/elev lined out, I'll try the F/D Focal Length in a couple of spots just to see if any improvement. The Ku was still stinking on the ends at this point.

I ended up with a .38 F/D and 48-1/8 Focal Length for the best Ku signal I can get on the ends, but it brought down the Ku in the middle without any elev/dec adjustment. I can't figure that one out.

Here is the best signal I have, and it still sucks:

G15 133W C-Band 3747 H California Channel 45% SQ that was at 60% prior to F/D adjustment.

G27 129W White Springs Ku 10-15% SQ Couldn't even get it prior to F/D adjustment. Got the other TPs which are now at 60-65%, but WS wouldn't even come in until now.

G10 127W 11720 V is at 30%

G11 91W 12060 V 45% SQ was at 65% prior to F/D adjust.
G11 91W C-Band 11720 H bouncing between 90-99% SQ hasn't changed either way.

G17 74W 11732 H ONN is now at 90% SQ since the F/D adjustment only at 75% before F/D adjustment.

AMC6 72W 12053 V satops mux 45% SQ was at around 30% before the F/D adjustment.

Tried AMC3 and couldn't even pull in Montana PBS. Tried AMC2 and couldn't get the test card digital or analog.

So how did moving the F/D ratio affect the ends for the better, and make the middle worse?

Where do I go from here?

Do I re-adjust the dec/elev now that the Ku is coming in better than before?

I am at a loss here.

The C-Band is fantastic. Gotta just get the Ku lined out.

Thanks for any help or suggestions. Will be out for a while, but back in couple of hours.

Fred

 

[linuxman]

Allright!

Just got off the phone with Mike Kohl. Whenever I want or need some answers even if they are answers that I don't want to hear or criticism that I might not want to hear, I can always trust Mike to tell it like it is. He is, and has been a world class professional satellite dish installer almost since the concept was thought out.

He told me that I was going about this all wrong and doing a lot of needless work.

He said that I should get an accurate way of measuring the elevation and setting the declination according to the charts and he suggested a digital angle finder. I don't have a digital angle finder. I just have the same cheapies that everyone else has.

But I did find my protractor. The string had broken a while back, so I just got through putting a new string through the hole and tying a button on the other side to hold it, and a squeeze fishing weight on the dangling side next to the markings.

So tomorrow, the declination will be reset to a 5.29 degree difference between the elevation and the total angle or at least as close as I can get it. Set the declination, lock it down and forget it. Don't move the declination again.

Then adjust elevation for best signal in the center. Find the best signal with movement of the Co-Rotor assembly in and out and best F/D ratio using the center satellite.

Then move to the outside ends and only make adjustments for side to side movement of the whole assembly, with possible elevation adjustments to get the best signal for both center and ends.

Then it is what it is.

Sometimes we all get to thinking that we are better than we are at doing something, and I think I have fallen into that trap.

Anole suggested as much yesterday, but was too nice to come out with it. Mike Kohl will spell it out for you in no uncertain terms. That's what I like about talking to him.

So hopefully I can wrap this up tomorrow.

Fred

 

[gabshere]

with some of mine i'm just setting up stationary c-bands and stationary ku dishes but its seems like for some satellites its the only way to get the best signal. plus it will work out for my wanting to get signals to several receivers

i will also be tuning a couple of ku dishes and one c band dish . good luck with the tuning

 

[tvropro]

Allright!

Just got off the phone with Mike Kohl. Whenever I want or need some answers even if they are answers that I don't want to hear or criticism that I might not want to hear, I can always trust Mike to tell it like it is. He is, and has been a world class professional satellite dish installer almost since the concept was thought out.

He told me that I was going about this all wrong and doing a lot of needless work.

He said that I should get an accurate way of measuring the elevation and setting the declination according to the charts and he suggested a digital angle finder. I don't have a digital angle finder. I just have the same cheapies that everyone else has.

But I did find my protractor. The string had broken a while back, so I just got through putting a new string through the hole and tying a button on the other side to hold it, and a squeeze fishing weight on the dangling side next to the markings.

So tomorrow, the declination will be reset to a 5.29 degree difference between the elevation and the total angle or at least as close as I can get it. Set the declination, lock it down and forget it. Don't move the declination again.

Then adjust elevation for best signal in the center. Find the best signal with movement of the Co-Rotor assembly in and out and best F/D ratio using the center satellite.

Then move to the outside ends and only make adjustments for side to side movement of the whole assembly, with possible elevation adjustments to get the best signal for both center and ends.

Then it is what it is.

Sometimes we all get to thinking that we are better than we are at doing something, and I think I have fallen into that trap.

Anole suggested as much yesterday, but was too nice to come out with it. Mike Kohl will spell it out for you in no uncertain terms. That's what I like about talking to him.

So hopefully I can wrap this up tomorrow.

Fred

What I think happens is we want to get more out of the dish than it is designed for so we try this that and the other thing, to get that tad bit more. But what happens is we screw up what we may already have had.

I know when I put up my G-10 dish this past summer I kept looking for more quality. I tried everything and many times had to start over just to get those original numbers back. I finally just said I guess thats it and ain't touched it for month's and its been working just fine with those same Q numbers.

It's human nature I guess..........

 

[linuxman]

I tried everything and many times had to start over just to get those original numbers back.

That is exactly what I did. I started over from the beginning.

When I went up this morning, I told my wife that today was going to be the day that I finished it. She asked "what if it doesn't perform like you think it should"? I told her that I would blow it off the roof if it didn't.

Thank God it is finally over!!!

I did precisely what Mike told me to do. Took a flat piece of steel to lay across the elevation bar and put my protractor and got my exact elevation, then laid the same piece across the back of the mounting ring to get the total angle. Then set the declination just over 5 degrees of difference. I tightened that down and didn't touch it again.

I adjusted the center for best signal, then started taking readings. I moved the Focal Length back out to the farthest point and tried moving in with both .40 and .38 until I got the best readings across the arc. It still wasn't giving me much and in some cases I was losing ground.

About 3:00, I was on G17 and ONN, and sitting there wondering why it wasn't maxed out. I had been doing the push down, lift up, but it just wasn't giving me any indication of what it needed. I had already tried moving the assembly in the direction that gave me some improvement yesterday, but that didn't help. I usually always move the whole assembly from side to side while at the center to keep the dish steady. This time, I decided to make ONN max out while I was looking at it so I loosened up the bolts and swung the assembly until ONN was at 99% and locked it down.

That did the trick and from there on all the others fell in place after adjusting their positions from the twist.

Here are the numbers from the Pansat compared to yesterdays.

G15 133W C-Band 3747 H California Channel 45% SQ now at 45%

G27 129W White Springs Ku 10-15% SQ now 75%

G10 127W 11720 V is at 30% now at 90%

G11 91W 12060 V 45% SQ now at 45% as compensation for the ends better quality.
G11 91W C-Band 11720 H bouncing between 90-99% SQ now at a solid 90% reflective of the Ku numbers on that position.

G17 74W 11732 H ONN is now at 90% SQ 99%

AMC6 72W 12053 V satops mux 45% SQ now at 75%.

Tried AMC3 and couldn't even pull in Montana PBS. Montana PBS at 60% SQ

Tried AMC2 and couldn't get the test card digital or analog. got the AMC2 (AMC16) digital test card at 89% SQ and got the analog test card.

I set up a DBS satellite just to make sure the used DTV LNBF was working and it works fine.

I unhooked the Pansat and hooked up the Traxis just for comparison so here are it's numbers:

G15 133W C-Band 3747 H California Channel Pansat 70% - Traxis 70%

G27 129W White Springs Ku Pansat 45% - Traxis 74%

G10 127W 11720 V Pansat 90% - Traxis 72%

G11 91W 12060 V 45% SQ Pansat 45% - Traxis 63%
G11 91W C-Band 11720 H Pansat 90% - Traxis 77%

G17 74W 11732 H ONN Pansat 99% - Traxis 80%

AMC6 72W 12053 V satops mux Pansat 75% - I still couldn't get these to come in on the Traxis. Very Strange.

Tried AMC3 and couldn't even pull in Montana PBS. Montana PBS at Pansat 60% SQ - Traxis 73%

Tried AMC2 and couldn't get the test card digital or analog. Pansat 89% SQ - Traxis I forgot to write it down.

The Traxis meter readings are very strange higher on some and lower on others. It is not consistent.

So the F/D ratio is .38 and the Focal Length is 47-5/8". That is 1/4" inside the mouth of the wave-guide.

I would put the dish overall performance right up there with the Birdview and probably the number 2 spot of all 5 BUDS.

I am going to run the coax into the house tomorrow afternoon and I will have final pictures.

Thanks for everyone's help, and thanks to Mike Kohl for forcing me back to the basics.

Fred

 

[tvropro]

Glad you got it Fred

I know my 12 foot Unimesh with just C band on it is touchy on C band because of the beamwidth but when you hit that sweet spot it smokes. May be related to your ku experience on a 10 foot. I think the mesh dishes aren't the best for Ku. A good solid offset will run rings around them. That's why Im using different dishes for different bands and always left my 12 foot for c band only. Years go I was going to put up a solid 6 foot for Ku but never did since other things in life took me away from the hobby and ku analog faded. I guess my original idea still are the best idea. Hence all my smaller ku dishes now.

 

[linuxman]

Thanks tvropro,

I wouldn't always agree about mesh dishes not being good for Ku. I too have several small offset dishes around on the roof, but they are there mostly for convenience in not having to move the BUD every time I want to change a channel.

I would put the Birdview up against any offset solid Ku dish anytime.

The problem arises when trying to get both bands on several different satellites. It is usually a compromise on something to get both bands with good signal all the way across the arc, but not always.

If the dish has great surface accuracy and the parabolic form is accurate, the mesh dishes will do just as good a job as the smaller offset will.

Sadly a lot of dishes were manufactured that didn't meet those high standards.

Fred

 

[tvropro]

Thanks tvropro,

I wouldn't always agree about mesh dishes not being good for Ku. I too have several small offset dishes around on the roof, but they are there mostly for convenience in not having to move the BUD every time I want to change a channel.

I would put the Birdview up against any offset solid Ku dish anytime.

The problem arises when trying to get both bands on several different satellites. It is usually a compromise on something to get both bands with good signal all the way across the arc, but not always.

If the dish has great surface accuracy and the parabolic form is accurate, the mesh dishes will do just as good a job as the smaller offset will.

Sadly a lot of dishes were manufactured that didn't meet those high standards.

Fred

My 12 foot has Ku mesh but I never upgraded the feedhorn Lnb for ku. The beamwidth is very tight on c band and Ku is 3 times more critical than c, so setting up ku could be a nightmare. As you saw with your 10 foot with a wider beamwidth.

I have found that a good offset like my Primestar 90cm will perform as well or outperform most mesh dishes on ku. Alot of it has to do as you said with mesh size and surface accuracy.

When your tracking the clark belt on a movable system you will never get 100% performance on all birds. While c band will be forgiving, Ku shows the limitations of your dish more. Due to tracking errors of the mount etc there will be some issue somewhere. The best thing to do is favor the arc where you watch tv the most and live with the marginal performance on some channels. If that one marginal channel is an important one to you? You may be better off to throw up an az-el offset for it and tweek it to the max. Probably will save you some headaches.

Anyway Im glad the Unimesh worked out. So when's the next project starting ??

 

[linuxman]

So when's the next project starting ??

I had several projects that I wanted to do this fall, but getting this fifth BUD up and running has been as you say, a "nightmare".

I still want to fine-tune the Pinnacle dish some more using the "Gold Ring" and Mike Kohl's procedure and I have the materials to do that but don't know if the weather will hold. A lot of great weather has already passed me by and we are at the time of the year here when it could become bad any time.

Last summer we had a storm pass through with a strong wind which cocked the Birdview on the 5-5/8" pipe that it sits on. The mounting cap was made for a 6" pipe and had a center bolt that came down from the top and screwed into the original mounting pipe that kept that from being possible. So I was holding mine on with the original 3 bolts which are pretty far apart with a 6" cap and they are along the bottom. The cap is also shorter than most because of the top bolt. I have since drilled out and inserted a total of 12 bolts in the cap. 6 around the bottom and 6 around the top. I adjusted it back as well as possible but need to hook up a receiver at the dish and re-peak it.

I also wanted to do some more multi-lnb experiments, but again time has passed me by.

And there is always dish hunting. I would like to find another 4 Birdviews and replace all my big dishes with them. (might not be possible in our area) Though I do know where two are, it is just a matter of getting them eventually.

I need to go dish hunting for a while while the leaves are off.

Fred