Ku lnb

[mreaves53]

Could a Ku lnb be strong enough to pull in FTA, but not strong enough to lock Digichiper II?

If I need a new lnb, what kind do I want to buy? Is the best lnb for 4DTV the best for FTA?

Thanks,

[elgemcdlf]

Are you getting Ku on G0 with the FTA receiver and the same lnb you are trying to use with the DSR922? I still think it is alignment.

[mreaves53]

On G0 I am receiving many different channels on the C-band side and the Ku side. On the Ku side signal level is 51% and signal quality is 52%.

I am also receiving Ku channels on X4 signal level is 50% and signal quality is 49-51%.

The channels I am receiving are listed on Lyngsat as correct for C or Ku.

I am using an Astrotel model PMJ Gold Label Series Digital Compliant Mini Ku LNB with 0.6 db.

Let me know what this info tells you.

Thanks,

[elgemcdlf]

Originally Posted by mreaves53

On G0 I am receiving many different channels on the C-band side and the Ku side. On the Ku side signal level is 51% and signal quality is 52%.

I am also receiving Ku channels on X4 signal level is 50% and signal quality is 49-51%.

The channels I am receiving are listed on Lyngsat as correct for C or Ku.

I am using an Astrotel model PMJ Gold Label Series Digital Compliant Mini Ku LNB with 0.6 db.

Let me know what this info tells you.

Thanks,

I can not find any information on the lnb you list which is really irrelevant anyway. If all you are getting is 51 & 52 respectively from G0 with a Fortec receiver & a 10' dish your alignment is off. As a matter of fact pretty far off. You should be more like 80 - 85 & 65 - 70 and those numbers are from a 8.5' dish which is not perfectly aligned. Since you report no Ku on the DSR922 & I assume you have it properly setup for your specific equipment I am starting to suspect you are in a side lobe and not even aligned on the true signal at all. Can you place an angle finder on your dish and tell us what it reads along with your location info?

Are you receiving the 2 channels on X0? Should be 600 & 601 on the DSR922

[mreaves53]

I am using the same lnb with the DSR 922. I can not receive G0 600 or 601. What angel do I need to measure? I will measure it tonight.

The one thing that doesn't add up is, when I added the Astrotel Co-rotator several months ago, X4 popped right in. Signal quality was in the 60's if I remember correctly. Why did I suddenly lose all of my Ku? We haven't had any storms lately to blow my dish out of alignment.

Thanks for all of you help.

[elgemcdlf]

Originally Posted by mreaves53

I am using the same lnb with the DSR 922. I can not receive G0 600 or 601. What angel do I need to measure? I will measure it tonight.

The one thing that doesn't add up is, when I added the Astrotel Co-rotator several months ago, X4 popped right in. Signal quality was in the 60's if I remember correctly. Why did I suddenly lose all of my Ku? We haven't had any storms lately to blow my dish out of alignment.

Thanks for all of you help.

If you rdish has a ring on the back side putting the angle finder on it should give a reasonable guess as to what you have it set at. I would guess you were in a side lobe all along and now the sat has moved a bit (called drift) and the side lobe is either gone or you are to far out of it to get signal. If you are not getting X0 600 and 601 not G0 600 & 601 I would play with adjustment for peak signal on the DVB receiver Ku for that sat including skew. You should at that time have it on the 922. If not or the very best you can get is the numbers you posted earlier we go back to side lobe and not really even aligned on the true signal.

Is your dish a one piece solid, solid panel or mesh? It is very possible your dish is warped. Again though I still think it is in aligment. If you can do no better than posted numbers find the adjustment for the dish and crank on it moving the dish up (mark the thing first) just keep going to see if you find signal somewhere else in adjustment. If not try down.

[mreaves53]

My dish is a 10' mesh with a ring on the back and a typical C-band actuator. Before I added the co-rotator, I measured the dish. I measured the dish to be 119" and depth to be 20.65". The FL calculates to be 42.9". It is not warped, but it is possibly out of align. Monday I measured the FL and found it to be way off for my dish measurements. I can not get the struts to allow the feed horn to be moved that far away from the center. I set the FD at 0.36. Could I move the feed horn further out in the scalar ring to increase the FL? As best as I can measure the feed horn is in the center of the dish and is parallel to the dish. When I did this Monday my quality numbers went up an average of 15 pts across the board.

Where can I find a good, easy to understand diagram of the angles I need to check.

I certainly appreciate all of your help. This is a mystery that is baffling me. Where I live no one close by works on C-band equipment, so I am left to having to learn how to do it myself.

[elgemcdlf]

Originally Posted by mreaves53

My dish is a 10' mesh with a ring on the back and a typical C-band actuator. Before I added the co-rotator, I measured the dish. I measured the dish to be 119" and depth to be 20.65". The FL calculates to be 42.9". It is not warped, but it is possibly out of align. Monday I measured the FL and found it to be way off for my dish measurements. I can not get the struts to allow the feed horn to be moved that far away from the center. I set the FD at 0.36. Could I move the feed horn further out in the scalar ring to increase the FL? As best as I can measure the feed horn is in the center of the dish and is parallel to the dish. When I did this Monday my quality numbers went up an average of 15 pts across the board.

Where can I find a good, easy to understand diagram of the angles I need to check.

I certainly appreciate all of your help. This is a mystery that is baffling me. Where I live no one close by works on C-band equipment, so I am left to having to learn how to do it myself.

Ok setting focal length. Forget the measurements and setup the dvb receiver and a small tv next to the dish. Now tryint your best not to block the dish slowly move the feedhorn in and out of the scalar ring until you peak signal. That shoudl solve that. I know not very scientific but it works Next on the list would be skew. I would set my dish to true south sat and pick a channel then peak by rotating the feedhorn in the scalar ring. Oh yes set the skew to 0 in the 922. This should get you reasonably close in skew and focal length.

Your H and V channels should be 90 degrees apart in skew. So if you have V channels on sat A set at 0 the H channels should be either 90 or -90. There should be a 90 degree difference between the 2. As to a site for setting up the dish look at the signature line on Wejones posts. He has a bunch of stuff online concerning dishes and most likely has something or at least a link to something.

[wejones]

Originally Posted by elgemcdlf

Ok setting focal length. Forget the measurements and setup the dvb receiver and a small tv next to the dish. Now tryint your best not to block the dish slowly move the feedhorn in and out of the scalar ring until you peak signal. That shoudl solve that. I know not very scientific but it works
....

The above is probably OK, and it's pretty much what I do, but there are a couple complications.
First, you have to be dead center on the sat for this to work. If you are on the edge or on a donut shaped spot (which is what the spot tends to look like when the focal length is off), then adjusting to the proper focal length may make the signal worse. Also, moving the throat in and out of the scalar ring is actually changing the illumination of the feedhorn. Really the adjustment should be moving the whole assembly in and out, but on most feeds, there is no easy way to do this.
What I do, is peak the dish on C-band making sure I'm dead on. There isn't much likelihood that there will be a donut shaped spot on C-band. Then I switch to Ku, and do what you say above. Recently my FL was so far off, that if centered on C-band, I could hardly pickup Ku, and to pick up Ku, I'd have to move the dish to tune on the donut. However after I did the above, now C and Ku show up at the same place, or at least a lot closer, because I didn't finish, because I was chased inside by the bugs.

[mreaves53]

I have measured and photographed my dish and feed horn. The back of my dish looks different than the one in the diagram on the Geo page.

I am 33.66 degrees N and 85.53 degrees west. My outside circumference is 119 inches and the depth is 20.5 inches. The distance from the inside the dish to the edge of the feed horn is 41.875 inches. The angle I measured on the ring on the back of the dish at G1 was 26 degrees and at G4 was 14 degrees.

I know I need another angle measure, but I have no idea where to measure. I believe my FL is still short, but I can not move the supports out any further. Could I put the supports on the front of the feed horn with longer bolts? That would give me another 1.5 inches to play with.

I do not know what type of mount this is, nor do I know how to make any adjustments. I think I found the N/S line on the dish, but other than that I am stumped

My photos are here: Satellite Photos

Thanks for all of your help.

[mreaves53]

In reading over literature on tuning my dish, I ran across the works zenith satellite and extreme satellite.

For someone in the south, East Central Al about half way between Birmingham and Atlanta, would the extreme satellite be W8? What would typically be the zenith satellite?

I am learning way more than I really want to know.

Thanks,

[elgemcdlf]

Measure the dish angle when pointing at your true south sat which for you would be the sat located at 85 degrees. Neither of the sats you listed are at 85 degrees.

[wejones]

Originally Posted by mreaves53

I have measured and photographed my dish and feed horn. The back of my dish looks different than the one in the diagram on the Geo page.

I am 33.66 degrees N and 85.53 degrees west. My outside circumference is 119 inches and the depth is 20.5 inches. The distance from the inside the dish to the edge of the feed horn is 41.875 inches. The angle I measured on the ring on the back of the dish at G1 was 26 degrees and at G4 was 14 degrees.

I know I need another angle measure, but I have no idea where to measure. I believe my FL is still short, but I can not move the supports out any further. Could I put the supports on the front of the feed horn with longer bolts? That would give me another 1.5 inches to play with.

I do not know what type of mount this is, nor do I know how to make any adjustments. I think I found the N/S line on the dish, but other than that I am stumped

My photos are here: Satellite Photos

Thanks for all of your help.

Your pictures are kind of big for someone like me with a dialup to handle, but I did manage to get the first two down.

First of all, your measurements above don't make sense. A circumference of 119 inches computes to a 3' dish, which is obviously not the case. I'm guessing that you mean a diameter of 119", or 9.9' . If so, if you feed that info into BJDISCALC2 , you'll see that your focal length should be close to about 43". This is just a ballpark though, because it's not always obvious where the actual outside edges of the parabola should be measured, since there is usually a supporting structure at the edges that isn't part of the parabola. Also, there is often a flat spot at the center of the dish, which doesn't follow the parabola. But 43" should be close.

In your first picture, where you show the inclinometer measurement, the surface you are measuring there is where you measure the actual inclination or aim of the dish, and is used to set the declination, although you should make this measurement when aiming at your true south satellite, and you should make sure that the inclinometer is vertical, like if you put a straight edge from bottom to top across that ring, and have the inclinometer flat against the fixed bar shown behind it. That surface should be compared to the a measurement of the fixed bar shown behind the inclinometer in the picture. The difference between these two measurements will be your declination. Again using the above calculator, you'll see you should use 4.82 for a declination. If you're aiming at a south satellite, you should be reading about 50.8 degrees elevation when measuring off the ring surface shown, and the measurement using the fixed bar behind the inclinometer, you should be reading about 55.6 (+/- a tenth or so), ie the difference at about 4.8.
Now, how to adjust to get the 4.8 difference? It's hard to tell exactly from the first 2 pictures, but again, in your first picture, you'll see that the dish rotates around an axis defined by two bolts, one at the bottom and one at the top of that fixed bar I mentioned above. From what I can see, the bottom bolt has only one hole that it can go through on the movable part of the ring, however the upper bolt I think can go through more than one hole, and/or might be adjustable to some extent, like in a slot. Some dish mounts don't have infinitely adjustable declination, but instead have 2 or 3 holes that give you different declinations, and you pick the one that comes closest to what you need. I know that one of my old dishes was like this. Other dishes have some way of adjusting declination very accurately. I'm guessing that you have the type with 2 or 3 holes, so if the difference between the two inclinometer measurements is close to 4.8, then just use it the way it is, but if it is significantly off, then you may have to try another hole to get closer to the proper declination. There may be some other way of adjusting declination that I can't see in the picture, but the upper bolt is the only thing I see that looks likely. It is also possible that there are 2 holes on the bottom too, which isn't visible in the picture, and there might be a variety of declinations possible by using different pairs of holes.
Anyway, you set this declination as close as possible, then peak your axis elevation (angle of the fixed bar) using signal reading on your south sat (zenith by your next post), then don't touch this adjustment again. Then go to your far east or far west sat (extreme), and tune in a sat by rotation the whole mount on the pole, while running the motor back and forth through the sat. Ie get a signal reading on the extreme sat, then make a fine adjustment by rotating the mount on the pole, then peak by running the motor back and forth through the signal. If your signal reading is now bigger, you are going in the right direction, if worse, reverse and go back in the other direction. Don't expect the signal to necessarily get better when you first move the mount on the pole. It will typically only get better after peaking using the motor.
Once peaked on the extreme sat, you are DONE. {unless your pole isn't plumb}

EDIT: One more thing. When making measurements with those inclinometers, be aware that depending on what surface you use, you'll either get the angle relative to horizontal or vertical {or 90 - angle}, so make sure you're using the proper surface, or subtract from 90.

[mreaves53]

What is the best brand and model of Ku lnb to buy to get the best 4DTV and FTA reception?

Thanks,

[pmb1010]

Originally Posted by wejones

Your pictures are kind of big for someone like me with a dialup to handle

People,

here is a neat little program that will allow you to easily resize those camera JPG's to more managble size for sharing:

IRFANVIEW
IrfanView - Official Homepage - one of the most popular viewers worldwide

After you get the JPGs from your camera on your computer, read them into IRFanview. Pick "resize/resample". Select 640/480, and re-save as a new JPG file. Upload those.