Gourmet arc set...

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highskies

SatelliteGuys Pro
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Feb 15, 2010
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I think this is what they are called. But anyway, does anyone have experience with these? The reason I'm asking is because I have a set I bought ages ago. My problem is not how to use them. That's not much of a problem. It's something else. Let me try and explain.

I found an abandoned 7.5' dish awhile back. I replaced my other one with this one. It was spring or so when I did this, so one of my neighbor's trees was blocking the eastern end of the arc. I could only see from about 137W to 105W. So now the leaves on the trees are all fallen. I can now see pretty much all of the arc. But I can't tune anything past 91W. I can barely get anything on that sat. I've tried readjusting my north south on the pole. That never helped. I tried adjusting my elevation angle. That didn't help. I have a Cband lnbf, and I checked the skew. It's pretty much where it needs to be, since both H and V tune in. I also made sure the feed was pointing at the center of the dish. That didn't help. I also checked the dish with 2 strings to see if it was warped. It checked out ok.

That only leaves one thing left..the declination angle. I'm pretty certain it's not correct. But that's a problem tho. I can't get the nut on the threaded bolt to budge. It's like frozen or something. It's not rusted or anything, but I can't get it to turn.
It will only turn if I was trying to go down the threaded bolt, but I need to go the opposite direction. It won't budge. So anyway, that's the reason for this post and the inquiry about the arc set. What I'm wondering is, since I can't adjust my declination angle, will this arc set still compensate for all of that, or does the declination angle have to be correct first, before the arc set can even work? I haven't used this arc set in like 10 yrs it seems, but now it looks like I might have a legit use for it, since it didn't really do much for me when I first got it.
 
Learned something new today. Many tools to use, but if you don't understand the geometry and how to measure which angle, and where to measure it, you'll turn aligning a BUD into a nightmare. No tool can tell you what angle you're measuring. I started with the angle locator, and use them exclusively for years. A while ago upgraded to a digital level. Understand that the arc-set is small enough to fit into tight quarters, but with a bit of ingenuity, All angles can be measured with the larger tools. Here's a picture that, I hope, explains the angles. These are for the standard declination table. The "Modified" declination decreases the declination angle slightly, and compensates at true south with a slight lowering of the polar elevation. Footprints by Dish Size - Latitude Declination Chart - C/Ku-Band Satellite Listing
 

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I got my arc set out yesterday, and positioned the dish at it's zenith. I finally got the declination nut to budge. It now matches the level of the arc set. I did the same with the elevation angle. According to the arc set, both were considerably off, both declination and elevation. Now the problem is, I'm not getting much of anything signalwise. Would this mean my true south was never correct? It's got me puzzled, because I would think the arc set should at least get you in the ballpark.

My longitude is 94.08°W. So which bird should I try to align my true south to? 93.1W or
95.0W? Also, does someone have a workable signal I can align to? It needs to be Cband, since my KU is on another dish and not this one. I have a 922 plus a standard dvb-s STB. I'd prefer to find a signal via the 922, either DC2 or analog.
 
Well, there's nothing analog on G 3, 95W that I know of, and I don't know of any DC2, not equipped. But there is 4167 V 6614 that you should be able to get with your DVB-S receiver. There is nothing 24/7 C band on 93.1W
The closest analog is at 97W (G17) 4060 vertical. That may work for you as it's only 3 degrees off of center, and that will fix itself as you adjust the azimuth going towards the ends. That sat also has some DVB-S signals. North & South America - LyngSat
 
Well, there's nothing analog on G 3, 95W that I know of, and I don't know of any DC2, not equipped. But there is 4167 V 6614 that you should be able to get with your DVB-S receiver. There is nothing 24/7 C band on 93.1W
The closest analog is at 97W (G17) 4060 vertical. That may work for you as it's only 3 degrees off of center, and that will fix itself as you adjust the azimuth going towards the ends. That sat also has some DVB-S signals. North & South America - LyngSat



THanks for the help. Even tho I never mentioned why, this Is why I preferred a DC2 signal instead. I have the worse luck with remotes for some reason. First it started with my 922 remote, then my 920 remote. Certain keys quit working on these. So I'm now using my 905 remote to operate my 922, since so far, it's the only remote functionung properly. But anyway, what do you know, the same fate has happened to my dvb-s remote.
A cpl of keys no longer function, namely the '4' and '7' keys. There would be no way I could program that signal into the STB, since it has 4s and a 7 in it. I sure wish there was a fix for when remote keys no longer function. But I suspect once that happens, you either have to live with it, or try and find a new remote.

I sure hope I get this dish properly back on the arc before spring comes, and all the leaves come back on the trees. My goal is to find 87W so that I can tune to some of those MeTV chs before it's too late..as in spring, when that side of the arc will be once again blocked by my neighbor's tree. But so far, I can't find anything past 91W.
On that bird I can't even tune in 3920 H without it tiling real bad. This time last yr when I had ny prev dish up, the one I replaced with this one, that signal was never a problem. I don't watch any of those lame EWTN chs or anything, it's just that I recall having no major problems with that signal on my prev 7 and a a half footer. I don't know why it's causing me hell on this one. At 91W I'm not too far from 87W. But until I get 91W peaked in properly, there's no way I'm even going to find 87W. I had absolutely no problems on the western side of the arc a few days back. It's always the eastern end that gives me hell for some reason. I would think with 94W being the top of the arc for me, 91W and 87W should be a piece of cake.
 
Have you tried cleaning the circuit board of the remote, using denatured alcohol? Also wipe off the carbon button that contacts the board. I've resurrected many non functioning buttons with it.

If you get one side of the arc, but not the other, Polar angle and declination are almost always incorrect. Check this page: Footprints by Dish Size - Adjusting the Polar Mount for Prime Focus Antenna - C/Ku-Band Satellite Systems - Tuning, Tracking, Azimuth, Elevation, Declination Angles, F/D Ratio, Focal Distance, Inclinometer, LNB/Feedhorn Assembly, Actuator Assembly, C near the bottom of page: Philosophy of tuning dish to sat arc.

neighbor's tree - - hire a beaver!
 
mumblings of an idea...

I really enjoyed this thread and the arc-set toy.
Also, the link above to the discussion 6 months ago was full of entertainment and enlightenment, too! :)
Guess I missed it.

Anyway, I once mentioned cheap inclinometers at Harbor Freight.
Here's a more current link to the product, and below I've included a picture in case they change their web site.

Anyway, I was thinking maybe you could get -three- and mark their dials with a dot of colored ink to indicate where to align 'em?
Sort of a poor man's arc set, eh? - :cool:
 

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Perhaps someone can diagnose this for me. Before I got the declination to change, and before I changed the elevation, all of this to match the arc set bubbles, I could, at 103W, get the signal with RFD TV, but the signal that contains the EON feeds, these tiled real bad and were pretty much unwatchable. Now that I have changed the declination and elevation angle, I now have the exact opposite. Now the Eon feeds are coming in pretty good, but I'm not even getting the RFD feed at all. It shows up on the signal meter of the STB, but not strong enough to produce any type of video. I haven't changed anything with my skew. It's where it was before. Both H and V work just fine on sats a little further west, such as 121W. I don't have any problems with any dvb-s feeds on that sat.
 
Could be, you're not exactly on the arc. The way to check is to go to 2 sats. One east and one west. as far from your true south as possible, but about equidistant from true south. Mark your mount, and when you adjust the azimuth on one, mark the pole with the mounts position. Then repeat on the opposite. If the marks on the pole are not on top of each other. the declination is off slightly. Now, I can't remember how to deduce if there's too much or too little declination, by looking at the marks on the pole. It's been a long time. But, I think, it goes like this: If the east sat mark is east of the west sat mark there is not enough declination. But it might be the opposite. Anyway, the object is to get the marks on top of each other. And it should be obvious if you adjusted the declination the wrong direction, as the marks would spread apart. I hope all that made sense. (If you adjust declination, readjust polar elevation at true south for peak)
 
Could be, you're not exactly on the arc. The way to check is to go to 2 sats. One east and one west. as far from your true south as possible, but about equidistant from true south. Mark your mount, and when you adjust the azimuth on one, mark the pole with the mounts position. Then repeat on the opposite. If the marks on the pole are not on top of each other. the declination is off slightly. Now, I can't remember how to deduce if there's too much or too little declination, by looking at the marks on the pole. It's been a long time. But, I think, it goes like this: If the east sat mark is east of the west sat mark there is not enough declination. But it might be the opposite. Anyway, the object is to get the marks on top of each other. And it should be obvious if you adjusted the declination the wrong direction, as the marks would spread apart. I hope all that made sense. (If you adjust declination, readjust polar elevation at true south for peak)




Thanks. I'm going to give all what you suggested a shot. The ironic thing about it, I have a motorized ku dish on another part of my property, that I installed myself probably 7-10 years ago, and it pretty much tracks the arc perfectly. I can't understand how I can be that good with ku, then fail miserably with Cband. Perhaps it's something to do with this dish I found last spring.
 
Well, they tune-up similar, but you measure angles differently on a BUD, and there's a new set of terminology to grasp. It all develops to the same thing though, a dish that pivots on and axis, and the dish is always aimed at the Clark belt. If or when I add a motorized Ku, I am sure I will run into problems. I have a bunch of experience installing 10 ft'rs, absolutely ZERO installing a motor on Ku. Notice my "motorized" Ku(mounted on the BUD)
 

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If or when I add a motorized Ku, I am sure I will run into problems. I have a bunch of experience installing 10 ft'rs, absolutely ZERO installing a motor on Ku. Notice my "motorized" Ku(mounted on the BUD)

I have a dual feed, and a Cband and a ku lnb that I now have laying around somewhere. I got tired of dealing with my neighbor's tree. Most of the KU I watch starts aound the top of the arc and eastward. Not too much ku on the western end of the arc from my location. So that's when I decided to install the offset dish. I had absolutely zero experience with it myself. At the time, I was a member of Sadoun's forum. Some of the guys there walked me thru the process. And before I knew it, I had sucessfully installed and tracked this dish. One of the local dealer's around here, before he got completely out of the BUD business, he was utterly amazed that I was able to do this. He was the one who basically walked me thru installing my first BUD in the mid 90s. He had a shop not too far from me, and I was over there constantly asking him things. Fortunately he never seemed to mind the questions. He was always very helpful for the most part. Now if I can just remember all the pointers he gave me back then.

BTW, it was too cold out today. So I haven't gone outside and messed with the dish again yet. The thing that concerns me is finding a signal on the eastern extreme, so that I can adjust the azimuth. The extreme west is no problem. I can use those 2 analog shopping chs at 139W I think it is. But what could I use on the eastern side, especially if I can't find anything past 91W? If I recall, I thought I heard someone say that CSPAN had an analog signal on the eastern end of the arc, perhaps 72W or something. Do you know if there is still an analog signal somewhere near that location?
 
You'll have to get used to aligning using DVB only as the analog are going to dissappear. When, is a guess, but I think it wont be too far off in the future. I don't know of anything analog east of your location. I haven't turned on a Toshiba in going on 2 yrs.
Most important angle is to get the declination set correctly. Without that, tracking is impossible. Then you find your true south sat, and adjust the polar elevation. Then move the dish east or west and peak your readings by nudging the mount one way or the other. If the declination is correct, the opposite side will be tracking also. Reviewing all of the thread -
BTW, is the arc set for your current location? I read they are for a 50 mile radius. Accuracy is everything, especially setting the declination. the rest is set by moving the dish and nudging the mount, while watching a meter, Q in a dvb, or analog meter.

My longitude is 94.08°W - - - so one of my neighbor's trees was blocking the eastern end of the arc. I could only see from about 137W to 105W.

So with the leaves, you couldn't see your true south sat?
If I had trees that bad. I'd be looking for a new loction for the dish. Branches, even without leaves, are going to really knock the signals down. I used to be able to get 139W all the time, then just in the winters, but not this year. The trees have grown enough that the branches killed it for me.
 
You'll have to get used to aligning using DVB only

This is exactly how I used to find birds to program their locations into the 922. I would use a known dvb signal, and once I found it, I would save that location into the 922. That's how I found some of those Cband Anik birds, with a dvb signal. But now with my dvb-s remote keys not all working, I'm not able to program any signals with '4' and '7' in them. In another post you asked if I had tried cleaning the contact board. I seem to recall trying that awhile back, but had no luck with it.






BTW, is the arc set for your current location? I read they are for a 50 mile radius.

I've lived at the same location since purchasing them. When I purchased it I do recall the dude telling me about the 50 mile radius. But not a problem yet. In that other thread that was linked to, in regards to the arc set, I read where some had problems with this set leaking after so long. So far so good with my set. Glad I didn't have that problem.



So with the leaves, you couldn't see your true south sat?


At the time, no. The other dish I replaced, it was tracking the arc almost perfectly. But it was years ago when I first installed that one. My neighbor's tree wasn't as much of a problem at the time. It still affected some signals on the eastern extremes, but I could at least see my south sat at the time. The reason the dish was replaced, was because a few tree branches on my tree which sits to the west of the dish, broke off in a storm and damaged a few panels. Then I found this one abandoned. Since I was able to at least track from 137W to around 105W, I assumed I must have gotten on the arc fairly close, even tho I couldn't see my south sat at the time. And now that the leaves are gone, I discovered I wasn't as close as I thought. Unless it's something else. Perhaps some of the tree branches are affecting some of this. The branches aren't real wide or anything, but the tree has def grown in height over the years.



I'd be looking for a new loction for the dish. Branches, even without leaves, are going to really knock the signals down.


If I could put the BUD where I have the offset dish located, I would have a clear shot at the skies. But I don't expect my neighbors would be too pleased, since this would be basically towards the street and in the front yard. Where I have it now, no one's ever complained. Well except for me, on account of my neighbor's tree. The offset dish is only 31". My neighbor's have no clue what it is. They probably think it's an over sized pizza dish. But since most have pizza dishes in their yards, no one has ever complained about the offset dish being in the front yard towards the road. But if I tried that with the BUD, I have a feeling it might not go over too well.



It's a funny story why I even purchased the arc set to begin with, in case anyone is wondering. I was having some problems with the HBO signals. On the 922, usally 40 or higher is what is required to not tile. The best I could do on the HBOs were 37 at best. It would tile quite often.
Then I noticed someone talking about arc sets. I started looking into it, and finally purchased a set, thinking it might help me tweak my dish better. When I got the set, and after reading the instructions, I pretty much figured out how to use them. I set the dish at it's zenith..checked the declination..the bubble was pretty much level. So then I checked the elevation..same thing again..the bubble on the arc set registered pretty much level. Then I went to the western extreme sat. Once again the bubble was almost level. Well, that was a hundred bucks down the drain, lol. But I finally figured out what the problem was. There was a long thick limb protruding from my tree that was affecting the signal. I opened the yellow pages and searched tree service..found a dude who would remove it for 75 bucks, and he could be there within an hour. So I went for it. Afterwards, the quality on the HBO's shot up considerably. Cost me 175 bucks total, since I invested in the arc set, which did me no good, since the dish was already pretty much spot on.
 
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It just seems strange that you've had to adjust the declination on the dish. I would think it would have been very close to what you need, unless you found this dish 200 miles, or more, north or south of your location. It also appears that since doing this, the tracking has not improved, but seems to have been degraded. All this just makes me question the accuracy of the arc set angles. Would be nice if you knew of a working BUD, in your area, to confirm that the angles on your arc set are correct. They are adjustable, and who knows, maybe smoeone has messed with them.
 
It just seems strange that you've had to adjust the declination on the dish. I would think it would have been very close to what you need, unless you found this dish 200 miles, or more, north or south of your location.


I understand what you're saying. I did find that dish in this area. It hadn't been used in ages. Perhaps whoever first installed it had no clue about declination angles and they just left it as is. Perhaps it worked ok with analog signals..I don't know. I'm pretty sure they retired the dish before they ever used it for digital feeds. Before the leaves fell, the western part of the arc was tracking just fine. That's when I discovered that the dec angle was probably wrong, when I was able to see most of the arc now. The Arc set showed it was off. So I finally got it to match the arc set, it fixed some things, but made other things worse.


Would be nice if you knew of a working BUD, in your area, to confirm that the angles on your arc set are correct. They are adjustable, and who knows, maybe smoeone has messed with them.


I don't know anyone around here with a BUD anymore. I'm sure there's plenty of BUD users here. But I wouldn't know any of them personally. The arc set should be correct, since it agreed with my settings on the other dish at the time. Perhaps my feed is not as centered as I think. Isn't the proper method to measure from 3 adjacent points on the outer edge of the dish to the edge of the feed?
If so, they're all showing the same measurements. This dish has quad legs, and none of them are bent or anything. I have an inclinometer also. My lat is 33.4 or so. The inclinometer was showing between 33.5 to 34 degrees.,,somewhere in there. don't recall exactly, since I'm not outside, but it's pretty much matching my lat for the most part i think. I can't find a good spot on the back of the dish to check the declination with the inclinometer. I guess I could check it on the face of the dish if I had a long straight 2x4 or something. At the zenith, I guess it would need to be showing around 38 or 39 degrees. That's just guessing, since I don't have the chart handy. But if I recall, I would add 5 plus degrees to the latitude. So I haven't checked the declination angle with the inclinometer yet. I only know that it now matches the arc set bubble.
 
Check your arc-set with your angle locator and see if the axis and zenith bubbles are declination degrees apart?
If it was put up 20 yrs ago, a dealer most likely installed it, and most likely set the declination. If they didn't, it would probably only work on 2 to 4 sats at best. Analog or digital. Might have used traditional declination chart and not modified. The difference between them is less than 1 degrees Footprints by Dish Size - Latitude Declination Chart - C/Ku-Band Satellite Listing
Here's a sure fire way of knowing if your declination is off, and how to correct it. PDF attachment.
 

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