123w and 129w with 1 Meter Primestar

[kstuart]

I have used lettuce ties - those big blue twist ties that keep the lettuce leaves together.

I was considering starting a thread with pictures called " Lettuce Get More Channels "

But over the long weekend, I replaced them with nicer looking twist ties.

Here's a Pic (I had that 30-inch dish pointed to 123w, but I didn't watch any of those channels, so I decided to use the dish exclusively for 129 for Dish-HD, hence the DishPro LNB):

 

[linuxman]

Hey kstuart!!

That's pretty cool too!!

Might give that a try somewhere along the way.

Thanks for the picture!!

Fred

 

[linuxman]

Ah!!! The sweet smell of success!!!

Before I write about the success in this update, I want to thank everyone who has helped out with suggestions, and ideas about how to accomplish this project.

I want to especially thank Anole who sent me a new modern LNBF and by the way, he has the fastest shipping West of the Mississippi. Mailed Wednesday at 7:00 PM from LA, and arrived here NW of St. Louis before 11:00 AM today using the Postal Service.

I also want to thank Keith Brannen and Kstuart for their many words through pictures.

Finally I want to thank Mike Kohl who really gave me the idea for this project with the pictures on his website.

I was going to try and buy another inexpensive LNBF, but couldn't find what I wanted right away to get it bought and shipped here before the weekend, so I decided to modify the feed-horn on the Hughes LNBF I have here that George sent me a while back.

I took an ordinary Dish Network LNBF and cut it down to the neck and a ring at the bottom with the feed-horn intact, and attached it to the Hughes LNB.

Here are the pics of that part:




As you can see, the feed part is a little longer than the original, and it was difficult to grind down all that metal with a dremel. I used several reinforced grinding wheels. Economically, it would have been less money buying the LNBF, but I wanted to give it a try.

I really wanted to take the stock Primestar LNBF off, and make sure I could get low enough and close enough with the G27 LNBF to make this work. By doing that, I had a different mounting point, and used a flat piece instead of the round rod I used before.

After Anole's LNBF arrived, I took both LNBF's to the roof to start the experiment. I had purchased some 3/4" conduit holders thinking that would be about right to hold the 20mm neck into the original junction block. It turned out to be oversize and I had to shim it with a piece of wood and double sided tape. I decided to go ahead and use the 84e (equivalent to 84cm) since it was already up and pointed to G10R instead of the 75e.

I got the modified Hughes mounted, and fired up the Pansat, and got 60% SQ on G10R 11720V. I had just gotten 75% with the original LNBF before shutting it down to bring on the roof, but the tube from the Dish LNBF has a ridge in it that I didn't want to go to the trouble to remove, and it is also has quite a bit longer neck than the original, so 60% isn't too bad.

Started mounting the Anole LNBF, and by doing it this way, it was very easy to move it in and out, and up and down just because of less moving parts.

The strong TP on G27 started showing up, so I wiggled and maneuvered until I got it as high as possible, then switched to White Springs, and continued the process to squeeze every ounce of signal I could get.

I ended up with 60% SQ on White Springs too, so I am very happy with the experiment, and will now pursue doing some more of my dishes like this. I just need to buy some more of the "inexpensive LNBFs".

Here are the pics of my setup, and then I have a couple of more questions:




How do you guys attach these 20mm neck LNBFs to the Primestar dishes?

What parts do you use, and where did you get them?

I like the fact that what I have is thin, and keeps the second LNBf close and low, but it needs to be held on more securely.

Thanks again to all who have helped.

Linuxman is very very happy today!!!

Fred

 

[Keith Brannen]

Ah!!! The sweet smell of success!!!

I knew you'd get it done! Excellent job of modifying the feedhorn. Of course, it would have been easier to buy another newer style LNB, but where's the fun and satisfaction in that! One of the things I enjoy (when they work, that is) about this hobby is modifying, fabricating, or adapting something to suit the needs of the situation.

How do you guys attach these 20mm neck LNBFs to the Primestar dishes?

What parts do you use, and where did you get them?

I like the fact that what I have is thin, and keeps the second LNBf close and low, but it needs to be held on more securely.

The round style tube bracket that I use for Echostar 7 & 8 comes with an insert (of course, I pop it out) in the LNB holder for a 20mm neck. Don't know if you could adapt one of those LNB holders to attach to a Primestar or not. If you look on my side photo of the dish with G11 on it you can see I took one of the holders and modified it so it would sit on a flat surface (cut and bent a piece of metal to the proper angle).

Once again, excellent work, and glad it finally came together.

 

[Anole]

I want to especially thank Anole who sent me a new modern LNBF and by the way, he has the fastest shipping West of the Mississippi.
Mailed Wednesday at 7:00 PM from LA, and arrived here NW of St. Louis before 11:00 AM today using the Postal Service.

You are most welcome.
But if I'd known you really wanted two, I might have worked out a 2-pack deal for ya.

I took an ordinary Dish Network LNBF and cut it down to the neck and a ring at the bottom with the feed-horn intact, and attached it to the Hughes LNB.

I got two empty LNB shells on my DirecTV Phase II dish when Radio Shack threw them out a few years ago.
Just have the metal casting inside the plastic body - no electronics.
I have a buddy with a lathe, and I'll ask him about making that mod.
Shouldn't be hard, and once set up, easy to do more all at once.
Provide a drawing or mark up a photo, with diameter and thickness of that base.

I had purchased some 3/4" conduit holders thinking that would be about right to hold the 20mm neck into the original junction block.
It turned out to be oversize and I had to shim it ...
....
How do you guys attach these 20mm neck LNBFs to the Primestar dishes?

I take the LNBs to the store with me and get conduit bracket hangers to fit.
They're never the size you expect.

Maybe try a 1/2 inch, and then mount it to one of the screw holes on your Primestar mount!
That'll put it off-center a bit, and slightly high.
Then, with a bracket or screw of your choice, mount a second hanger bracket to the other hole...(?)

Also . . . the stuff inside the tube might be important.
Might be something to match the RF waves to the stub down at the PC board.
My retired TV station guy is off in China this week, so I can't ask him.
(maybe he'll bring me a sample...)

 

[linuxman]

Thanks Keith!!

I'll look at the picture more closely on your G11 setup.

Hey Anole!!

It worked!! That's a pretty good LNBF. The signal is nice and strong, and seems really stable.

I got two empty LNB shells on my DirecTV Phase II dish when Radio Shack threw them out a few years ago.
Just have the metal casting inside the plastic body - no electronics.
I have a buddy with a lathe, and I'll ask him about making that mod.
Shouldn't be hard, and once set up, easy to do more all at once.
Provide a drawing or mark up a photo, with diameter and thickness of that base.

Here are a couple of dimensions for your buddy. Seems like a waste not to use the original LNBs, but if the feed-horns get in the way, they are useless. On the other hand, time spent to make something may not be worth the cost of new LNBFs.

I take the LNBs to the store with me and get conduit bracket hangers to fit.
They're never the size you expect.

That's what is sad, I did take the piece to the store, but I didn't take the piece out of the bag. When I slipped it over the neck, it seemed nice and tight, but the loose part is at the top. not on the sides. Ah well, I learned something new.

I also read in another post where George (Gabshere) used half of a grounding block. I am going to look at those next time too.

Also . . . the stuff inside the tube might be important.

The ridge inside the Dish tube looked like it was nothing more than a dialectric insert to straighten out the circular signals. I could be very wrong about that.

Inside the Hughes LNB, there are two probes. One goes all the way across, and the other is only halfway across which is further back. I lined up the ridge with the probe that only goes half way across which is at the top and the ridge is now at the bottom.

Thanks again,

Fred

 

[Keith Brannen]

Thanks Keith!!

I'll look at the picture more closely on your G11 setup.

Whoops. I just checked the insert for the LNB holder I mentioned, and it measures 30mm (not 20mm, as I thought), so it wouldn't work unless you found an insert for that insert!

 

[linuxman]

Ok Keith!!

Thanks for checking!

Fred

 

[Anole]

bracket clarification

Just to make myself more clear....

When I said use a hanger bracket sitting on top of one of the primestar LNB mounting screw locations, I meant the kind of bracket shown in post #28 of this thread.
I don't know what you are calling that "half-round" bracket you are using to hold the 20mm neck of the Primestar LNB.

 

[linuxman]

Hey Anole,

I tried that kind of holder with the rod the first attempt, and using what I currently have actually worked better for me.

Here is a pic of a Primestar mounting block and a pic of what I used to fasten it down into the groove with.



I just wish it fit a little tighter.

I am going to try and find the ground clamp that George talked about in one of the Primestar threads. I think it might work a little better.

Fred

 

[Anole]

Yes, I know the ground clamp.
It's a good idea to replace the bracket you have.

I was talking about putting the wrap-around hanger bracket slightly off the boresite of the dish, and have it grab the neck of the LNB, to allow the secondary LNB to move in a bit toward the center.
Likewise, it'd give you a good grip around the neck. . . if you like that sort of thing.

 

[linuxman]

Ah!!

Now I understand what you were getting at.

That would probably work too, just haven't tried it. I might give something like that a shot on maybe G25 and AMC3 combo, or AMC6 and AMC3 combo.

It would work for these two as well, but I already have this one set, just need to do something different with the feed, and the way it attaches.

I even had a thought this morning about taking the original feed, and modifying it a little for instance as this pic shows.



That would allow for the thinner type hold down bracket and a little adjustment in and out from the dish to add a bracket on the side.

I even thought about modifying the feed itself to make it more round that eliptical shaped.



At least that would help with it being in the way of the second LNBF. I doubt you would lose much signal cutting that much away.

Only an experiment would tell. The main thing is to change the thick holding wings where the bolt passes through, and the oversized scaler feed reduced. Then the original LNBFs would be fine.

What do you think?

Fred

 

[linuxman]

While we are talking about cutting away the original Pstar LNB Feed horn, take a look at these two pictures.



In the first picture, all the scalar rings are the same distance from the dish all the way across on the side that runs from East to West. That is the wide sides of the dish. The vertical parts of the scalar rings are for the top and bottom of the dish.

I don't see anything wrong with cutting away everything all the way around from where it is marked in the second picture.



You would end up with basically a round feed horn verses the eliptical shaped one. The round one I put on the dish yesterday didn't seem to have a problem getting signal.

After all, the scalar rings are for keeping out TI aren't they? They really don't help with pulling in signal do they?

Anyone with an idea, let me know what you think!!

Fred

 

[caddata]

....Let me know what you think....

Well Dr. Frankenstine....er I mean Fred:

Some fine surgery you're doing on those LNBF's. Dissected my first Channelmaster Ku feedhorn last week to find it no more than a funnel. Thought I'd find something more exotic behind the lense.

Keep up the posts, this is more fun than the Birdview project.

Harold

 

[linuxman]

Thanks Harold!!

I saw someones signature here on Satellite Guys who said they wanted to be a mad scientist when they were a kid.

They probably didn't want to be one any more than I did.

I love this hobby, and there is always something to peak your interest. I don't want to kill the Primestar LNBF, I just want to see how far I can trim it and still have a working product.

Do you know whether or not it would kill the signal if I trimmed the Feed-horn back as much as I have proposed in the previous pictures?

I have an extra feed-horn or two, but just curious if this is a futile effort?

Thanks always for your engineering expertise!!

Fred

 

[Anole]

making horns

I go away for the day, and all hell breaks lose here.!

Well, here's what my machinist friend came up with for modifying the Dish LNB horn to fit Primestars...
it's probably not worth the effort, but . . .

One idea to hold it in the lathe to cut it down, was to stick some sort of expanding pin into the horn from the board side.
We could make one, or maybe buy the device he described, for a few bucks.
It's basically a rod about the diameter of the inside of the feed pipe, split down the sides, with a bolt in the end.
When you snug the bolt, the rod expands.

A second way was to mount the horn between some centers on the lathe, and dog one side down...
You spin that and cut away whatever ya need to make the part.
He seemed to think this was the easiest way.

All these ideas start with bandsawing most of the base casting away, but not too carefully.
He's got the bandsaw, and these little castings should cut like butter.

He was interested in making a few if they were really useful, for lunch money and shipping, if someone supplied the horns and took off the white caps.
The DirecTV sample I had was mechanically different and would be harder to rework than the Dish unit used in the above posts.
We'd do mine as a test, to see how that would be, before taking on any more.

He also suggested maybe if we have the material in the casting, cutting a little grove in the side that goes to the LNB, to lay a standard O-ring into.
Without a real LNB to bolt up to, deciding where to put that grove would be hit or miss.

Again, probably not really worth the effort . . .

I'll get back to ya on some other ideas later tonight or tomorrow.

 

[linuxman]

Hey Anole,

One of the problems that I ran into which I didn't write about. The post was already huge. The dish tube material at the point where it hooks to the LNB was too thin for the two halves that you bolt over it to hold it to the LNB. I ended up putting some double sided tape in mine to hold it, and it still isn't really thick enough.

The part I am talking about is marked 4mm in post #46 above. The casting just wasn't that thick. There isn't any way to build that up to make it really snug.

That's what you run into when experimenting. You never know where the experiment will bite you in the backside.

As your machinist guys said, it probably isn't worth all the effort, but it is fun trying.

Fred

 

[Inno]

In the search for another satellite to add to the "collection" as I have a spare opening on my disecq switch, I searched for "whitesprings" and came up with this thread.........and a good thing too.
Currently I have employed the "Iceberg" method of LNB installation on my 1m star choice dish which was (and still is as far as I know) tuned only to G-10R. I had no problem finding Whitesprings but the quality is a little low around the 45-55% mark and fluctuating.......thinking I might have to trim some more trees but I think it'll be quite watchable. I'm guessing the wind blowing the branches around is causing the fluctuation.
I'll post some pictures later once I get the new wires run etc. At any rate, I just wanted to thank you for posting your experience/trials here and making it that much easier for me to impliment.

Cheers!:up

 

[linuxman]

Hey Inno!!

Glad you liked the thread!!

I have always hoped that my "experimentations", trials, and tribulations might help someone else. Some of the tribulations I bring on myself.

There isn't a thing wrong with Iceberg's method of attaching an LNBF. I still have a DBS LNB attached to my motorized Primestar 84e that way, and it has worked fine since last fall.

I'll look forward to your pictures. I love good pictures.

Fred

 

[linuxman]

Well the experiment continues.

I have modified the original Primestar/Hughes LNB Feed like I described above. Just have to wait between rain to give it a try. Probably tomorrow morning.

Here are the pics of what I was talking about above:







After the modifications above, I can now attach it with a half of the clamp above, and have a nice solid thinner piece to attach to. The LNBF has been trimmed down so it won't get in the way of the 2nd LNBF. The thing now is to see if it has lost any signal by the trim down.

George, that ground clamp idea was pure genius. I found the above ones at Lowes this morning for $1.67. I modified it just a little, but now have two working halves to use and have a spare for more dishes. The holes line up perfectly, and they are solid without being too thick like the original.

Hope it clears soon, so I can give this a shot.

Fred