New to FTA and need help installing LNB and a few other Questions.

[aebcoat]

A few weeks back I bought a sonicview 360 receiver and a linear LNB. I briefly tried to use an 18in dish I had but had no luck so I went searching for a larger dish. Posted an ad online and someone gave me a dish. It is 56in in diameter and 12 in deep so it should be plenty large enough for Ku. Only problem was that the lnb mounting hardware was missing. I researched how to find the focal point and saw the equation

Diameter x Diameter / Depth x16

I calculated the focal length to be 16.9. One of my questions is where to measure from, is it 16.9 from the back of the dish, or from the front face?

Also does anyone have any ideas on how to make a lnb mount for this dish? You can see my attempts in the pictures, but I had no luck.

I aimed at 123w (G18) and had very high signal (which i know is mostly meaningless,) but 0 on the quality. I used dishpointer to get the correct compass direction but struggled for awhile and never got anything, This dish doesnt have any elevation markings so I dont know the best way to deal with that.

Looking at the pics can anyone give me any advice on this dish? I dont believe its an offset dish so I tried putting the LNB in center. Also pictured is my southern view which has alot of trees, will those trees totally kill he signal even with that large of a dish?

 

[eurosport]

Looking at the 1st pic, your homemade LNB mount looks like it's protruding at a slight angle and not straight out...
This will put the LNB out of the "sweet spot" or focal point. It also appears like it's too close to the dish face, but that just may be the pic that makes it look that way.
If those trees in the last picture are between your dish and the satellite you're looking for, they probably will block the signal.
It also looks like the dish is pointing way too high in the sky for G18.
Hope some of this helps you, even if it sounds like all I gave you was bad news.

 

[zamar23]

I'd say that you may have a better luck driving to a nearby sat store and buying a new 39" offset dish. Or simply keep searching around for a better donation. Once you found a dish and figure out the best mount point, use Obstacle Elevation Calculator to see, if the trees will block signal to 123W, which is not really south of you at all. You may put a better suited dish on your house roof to avoid signal obstruction.

 

[aebcoat]

Looking at the 1st pic, your homemade LNB mount looks like it's protruding at a slight angle and not straight out...
This will put the LNB out of the "sweet spot" or focal point. It also appears like it's too close to the dish face, but that just may be the pic that makes it look that way.
If those trees in the last picture are between your dish and the satellite you're looking for, they probably will block the signal.
It also looks like the dish is pointing way too high in the sky for G18.
Hope some of this helps you, even if it sounds like all I gave you was bad news.

Thanks for your opinion, even if it is some bad news

So the LNB should be straight out and not angled at all? It may have been at an angle as my homemade mount wasn't real tight. You also mentioned it looked too close to the dish, that was what I am really curious about. I calculated the focal point using the above equation. In that picture it is measured from the back of the dish. Should I add 12 inches (depth of the dish) to my number and make it that far away, which would be about 28 inches out? If I get a definate answer from someone I should be able to craft a mount for it from PVC. Just want to make sure before I do so.

Also does anyone have any tips on how to measure elevation when their is no scale on the dish? In the 2nd picture you can see the 1/2 circle base that the dish pivots on to adjust elevation, but their is no scale to go by.

Yes the trees are in the path of the dish, I didnt know if it would totally kill the signal, or just weaken it some. I am going to have a hard time getting around them I fear .

edit
@zamar, Unfortunately I haven't seen many satellite retailers around here. The few I have checked only deal with DN, still have a few more to contact though. Also have a few other emails from people with dishes, they may be small 18 inch ones from the sound of the email but I am still going to contact and ask for pictures to decide. I will look around the yard some for a better mount point and use the obstacle calc to see if I can get over them,

 

[turbosat]

That dish looks like my Little Wil 5' c-band dish. Its a prime focus dish, and has an alum shaft sticking up at the bottom edge of the dish to hold the lnb in the right spot. You really need a ku feedhorn with a ku lnb on it if you're going to use that dish, and prob fashion some lnb-support arms out of tubing to hold the feedhorn in the right place. Not exactly beginner stuff but it can be done. I started out with fta trying to use that dish and said lnb/feedhorn but then found an old primestar dish to use. And even though its a lot smaller than that metal dish-it performed much better, as it'sa dish designed for ku signals. Look around your area for one, they are still available,usually for the asking. Hope you aren't trying to see thru all those trees though, you won't have much signal that way!

edit: I"ll check my old dish tomorrow and let u know about the depth, I bet its the same dish because mine has that ring to sit on too.Wind blew it over and bent the dish back in May so I haven't messed with it since (got a pile of dishes lol). I think the distance is
27" but cant find my notes tonite. You need an angle-finder to help set the dish up, one of those magnetic-base types. But I think you'll have trouble with those trees if they are to your south and SW/SE.

 

[aebcoat]

Ack. Again with the trees lol. Thanks for the advice, It what I assumed already. What size primestar dish did you use? I have asked a few people to email me pictures of their dishes, Had 2 people tell me they have 3 dishes each. Some were direct tv and they didnt mention what kind the others were. I am hoping one may be a 20-24in circular or elliptical one, and not just more small 18in ones like the other I already have. Hopefully they have LNBs aswell so I will know exactly where they need to go. I saw a fairly large dish, maybe the same size as that one laying in an alley behind a post office with all the hardware and an lnb, but they said they still need it May have to ask again as its been on the ground for a few months now

If I can get a smaller dish I will have more freedom on where to put it, which may help get away from some of the trees.

i am actually testing it at my parents house, I would like to eventually setup a small system at my apartment but that dish wouldnt even fit on my porch, let alone have enough room to move so a smaller dish would be needed anyway. But that wont happen for awhile as I have no south sky LOS from my porch and I am on the ground floor surrounded by other buildings. Only 5 more months on the lease though

 

[eurosport]

Thanks for your opinion, even if it is some bad news

So the LNB should be straight out and not angled at all? It may have been at an angle as my homemade mount wasn't real tight. You also mentioned it looked too close to the dish, that was what I am really curious about. I calculated the focal point using the above equation. In that picture it is measured from the back of the dish. Should I add 12 inches (depth of the dish) to my number and make it that far away, which would be about 28 inches out? If I get a definate answer from someone I should be able to craft a mount for it from PVC. Just want to make sure before I do so.

Also does anyone have any tips on how to measure elevation when their is no scale on the dish? In the 2nd picture you can see the 1/2 circle base that the dish pivots on to adjust elevation, but their is no scale to go by.

Yes the trees are in the path of the dish, I didnt know if it would totally kill the signal, or just weaken it some. I am going to have a hard time getting around them I fear .

On a prime-focus dish, the LNB needs to be exactly in the center.
As for the focal point, I would try moving it out a little bit at a time until it starts to see a signal.
But, in this case I see so many variables, like LNB skew,
...finding the focal point,
...no elevation scale,
...and the trees,
that it may be a very frustrating task to get this thing to work.
In this case, I'd be inclined to try and find another dish, that has an LNB arm, and an elevation scale. It would make things much easier for you to snag that first signal. Just my opinion, good luck.

 

[aebcoat]

On a prime-focus dish, the LNB needs to be exactly in the center.
As for the focal point, I would try moving it out a little bit at a time until it starts to see a signal.
But, in this case I see so many variables, like LNB skew,
...finding the focal point,
...no elevation scale,
...and the trees,
that it may be a very frustrating task to get this thing to work.
In this case, I'd be inclined to try and find another dish, that has an LNB arm, and an elevation scale. It would make things much easier for you to snag that first signal. Just my opinion, good luck.

Yeah, That was my feeling, just didn't want to accept it Too many variables to overcome for a starter setup. Hopefully i am able to snag a good dish soon. I don't mind buying one, but would prefer to do it locally as shipping is killer. At least I am not in a lot of money with dishes that dont work as the 2 I tried were free, though my car broke down after I picked this dish up and I was stuck 30miles from home replacing a belt on the side of the road :rant:

I appreciate everyones advice, hopefully I can snag my first signal in the near future.

 

[freezy]

Is that it?

 

[aebcoat]

Is that it?

Looks like it could be, Mine doesn't have any manfu. names on it that I can see. However the part on the bottom is only a 1/2 circle, though i suppose it could be missing the other piece aswell as the piece that goes up.

 

[zamar23]

You may want to read Online Microwave Antenna Book to learn more about sat dishes. Assuming, you have a good Sat Meter and can find a focal point by moving the LNB along a much longer post, your main challenge would be to angle the dish properly, which can also be roughly done using an Inclinometer attached to the dish rear center. Then you need to refine its aiming looking at a small TV outside your house. Don't forget to account for magnetic declination when using a compass to find the right azimuth. You'll learn a lot along the way.

 

[Tron]

Some were direct tv and they didnt mention what kind the others were. I am hoping one may be a 20-24in circular or elliptical one, and not just more small 18in ones like the other I already have.

The DirecTV dishes won't work for anything except a couple of free channels on Dish Network's satellites, unless you can find the larger DirecTV World dish. The World dish has a linear Ku-Band LNB, so it will receive most FTA. Another dish you might come across that is useful for FTA is the Dish Network Superdish. It, too, has a linear Ku LNB, but the one on the Superdish is stacked (not the easiest to set up for a beginner).

You really need at least a 30 inch dish for reliable linear Ku-Band reception. Bigger than that is better. If you can find a Primestar dish, that will work best.

 

[eurosport]

Yeah, That was my feeling, just didn't want to accept it Too many variables to overcome for a starter setup. Hopefully i am able to snag a good dish soon. I don't mind buying one, but would prefer to do it locally as shipping is killer. At least I am not in a lot of money with dishes that dont work as the 2 I tried were free, though my car broke down after I picked this dish up and I was stuck 30miles from home replacing a belt on the side of the road :rant:

I appreciate everyones advice, hopefully I can snag my first signal in the near future.

I'd keep this dish, but just set it aside for now. After you get used to aiming and peaking a more "normal" one, you can always go back to it,
and have a better shot at making it work.
Then when friends come over and see it, you can say "I built that dish!" :up

 

[eurosport]

As you travel about, keep an eye out for a Primestar dish like this.
they're the best Ku dish out there in my opinion,
and usually free for the asking, dish, pole and all! :up

 

[turbosat]

Hey euro , one day when it quits raining, a coat of paint will spruce up the old primestar, lol.
I wouldn't go purple though, like I did on one of mine, I'm thinking its about time to change that back..

 

[aebcoat]

Thanks for the pictures, Ill keep an eye out for those primestar ones. As I was driving to pick this dish up I saw atleast 5 black BUDs that still looked to be in use. My parents had one when I was younger too.

I plan to keep this one, just store it somewhere out of the way. At my parents place they have a pretty large field that is pretty flat and clear next to the house. I can probably setup a dish on a pole mount at the far end and that would put me a few hundred feet away from the trees which may help me clear the tops of them.

I may look and see if i can find a cheap/free portable tv to take with me, then just run an extension cord for it and my receiver. Would be much easier for testing then running a few hundred feet of coax and using 2 way radios to talk to someone inside at the tv.

turbosat I read to avoid dark colors when painting dishes as that will make them hot and could melt the LNB, Have you ever heard of that?

 

[turbosat]

LOL Yep I have heard that about painting dishes dark colors. Mine's not real dark though, and we don't hit the hundred degree mark very often here, thankfully, so I prob don't have a lot of worry on melting the dish. It was just for fun when I couldn't find the paint I wanted, haha. I'll prob turn it desert camo next.

 

[eurosport]

Hey euro , one day when it quits raining, a coat of paint will spruce up the old primestar, lol.
I wouldn't go purple though, like I did on one of mine, I'm thinking its about time to change that back..

IF it quits raining! I think one of my 1.0's has grown to a 1.2 now!
LOL

 

[zamar23]

I guess your LNB has melted evenly all around the dish adding to its size.

 

[aebcoat]

Turbosat, Just saw your edit and wondered if you got a chance to measure the depth/focal point on yours? If I can find a portable tv i can relocate on the property to avoid the trees. My limiting factor now is the length of my coax. If I can find a good spot with a portable TV and a short coax I could get the proper length to do a proper setup. Will just take some creativity and patience to get setup.