Ku OMT questions

[kittyhas1000legs]

Hey all,

I'll be setting up my dish in the next week or two (holy crap, finally). It's a former Muzak dish, I think CM, 1 meter fiberglass offset with a feedhorn to match the dish. It came with one single-polarity LNB. I was able to get a second LNB and Ku OMT off of an ooooold Hughesnet dish, and it seems as though they all fit together. I attached the two Norsat LNBs the OMT, and the feedhorn (conical scaler?) to the front of the OMT. It seems to all fit together.

First, will it actually work? Do I need a specific OMT, or should the one off the old internet dish work, so long as H is H and V is V? The dish still holds the conical scalar at the same exact position as before, but the LNBs are in a different position due to the OMT.

Next, what's the best way to power the LNBs? I assume the best would be 18V to each. I'd like to keep it relatively easy to start, so I was thinking I would use one of my clearance Radioshack 3x4 multiswitches to provide 18v to H and 13v to V. I'm aiming for 125W, so I'll be trying for H for all the main PBS channels. The feeds and any surprises on V would just be icing on the cake.

I know everyone loves pictures. I'll see if I have any on my phone, otherwise I'll post in a week or so once I'm relocated in CO.

 

[Magic Static]

That Hughesnet "OMT" as you call it is a single polarity rig too. The feedhorn of the Muzak dish has an insert to reject the other polarity. I ground out mine to work. I put a dual polarity LNB on in place of the one that came with it.

 

[kittyhas1000legs]

Here are the few relevant pics I have on my phone. The feed ends at just a circle. The lnb itself has an almost rectangular opening. Again, I know much less than most here.

I'm not sure how much it matters, but it's a very old Muzak dish. Most I've seen have a logo like an m in a circle. This one predates that.

 

[danristheman]

Kitty I have the exact same thing you can bolt up a dn super dish lnb its stacked so scan V you can put it on 97w ku.

 

[kittyhas1000legs]

Kitty I have the exact same thing you can bolt up a dn super dish lnb its stacked so scan V you can put it on 97w ku.

The only concern at first will be 125W. If I get a second dish it may end up on 97W. All my wife and I really watch is PBS, so anything beyond that would be just for fun.

That Hughesnet "OMT" as you call it is a single polarity rig too. The feedhorn of the Muzak dish has an insert to reject the other polarity. I ground out mine to work. I put a dual polarity LNB on in place of the one that came with it.

I'll check once I get to my stuff in CO, but I'm pretty sure that insert came right out of the feed (or did something fall out of another part I had? Memory is fuzzy and parts are far away.) I guess I got my hopes up with the old Hughes pieces, but at least I have two Norsat Ku LNBs.

My other annoyance will be trying to find something to cover the feed. The end is ever so lightly larger than a Pringles top.

 

[FaT Air]

Get yourself a large soda bottle. Some leather gloves, and a heatgun. Heat form a cover from an appropriate sized piece of the soda bottle. You may need a second pair of hands to operate the heat gun while you pull the plastic into shape.

 

[kittyhas1000legs]

Now that I'm starting to get unpacked, here are a few pictures of what I have. The first pic shows why I thought it'd be an OMT. The second shows the front where the feed attaches. the little round-to-rectangular insert did come right out of the Muzak feed.




The round part where the transmit part of the old Hughes dish attached is where I thought the H LNB would attach. In the bottom right of the third pic is a ring that was attached to the transmitter and also has holes that line up perfectly for an LNB.



At the very least, if all those extra parts are useless, I'll have one polarity for most of what is on 125W, plus an extra LNB for future use.

 

[kittyhas1000legs]

Next question: why doesn't it go back together as easily as it went together? If you look at the third pic I had initially posted, the arms hold onto the feed holder nicely. Now as I put it back together, I get this:


The angle's all wrong. The side arms are identical (I tried swapping them). I can't turn the arms around, since the other end is angled and has a larger hole for the bolt that goes into the side of the dish.

I guess I'll be playing with it tomorrow before I go to work, and after I mention to the landlord that the grumpy neighbor thinks my balcony is unsightly.

 

[Cham]

I just used some 14ga insulated CU wire on the original feedhorn clamp and replaced the feedhorn with a standard LNBF. It's about 1/4" higher in the clamp than it should be because of the larger diameter circumference of the standard LNBF unit, but it works much better than the original feedhorn/LNB combo I had. Actually holds the LNBF quite tightly. One day I'll look for longer bolts for the original clamp and use it's upper half.

 

[FaT Air]

Are you sure you have the arms in the correct position?? (bottom arm is on a side now???)

 

[kittyhas1000legs]

Are you sure you have the arms in the correct position?? (bottom arm is on a side now???)

Yes, the bottom is much shorter than the other two. As I tightened things, they seemed to line up again. I had to give a wiggle here, a turn there, turn a bolt around, but it seems to fit right. In the morning I'll hook it up to my nova-s2 card and see if the Ratshack satellite finder sees anything, and talk to the woman in the rental office. I still kind of want to try the part from the Hughes dish, but first I'll just use the original feed and lnb to get things lined up correctly.

 

[kittyhas1000legs]

Welp, I got the Radioshack satellite finder to scream at me, but the mix of software and WinTV Nova-S2 can't find anything. I guess it's time to get me a bright red Amiko A3 and start blind scanning.

 

[FaT Air]

does it stop screaming if you place your hand over the feed throat?? Might just have the gain set too hi.