Prodelin 1.2m offset on Birdview H-H mount

[phlatwound]

I am trying to mount my Prodelin 1.2m offset dish on my 70:1 Birdview H-to-H mount and would like to get some input on setup angles.

The main elevation bar of the BV mount is showing 37.5 degrees for now, was shooting for 37.6-36.7 but that's close enough for now.

The top flange (where I have my dish pivot bracket mounted) of the BV mount is reading 42.6 degrees. I *think* the approximately 5 degrees difference between this reading and the reading at the main elevation bar is the +/-5 degrees of declination that is built into the mount from the factory.

The Prodelin dish frame (should be approximately parallel to the dish face) is reading 70.8 degrees (this is the maximum angle I can get now, before the Prodelin frame hits the main elevation bar on the BV mount). Placing a straightedge from edge-to-edge vertically on the face of the dish gave me a reading of 71.5 degrees.

I just have the brackets mocked up on the BV mount at this point, I think I could get another 2-3 degrees downtilt if I needed it.

I have been told that the offset angle of this dish is 22.6 degrees and have attached pics of the angles taken from the LNBF support arm.

I am at 37.15 N lat, 93.66W long.

My true south sat is 93W, setup angles for my location are Elev: 46.9, Decl. -5.89


Any help with figuring this deal out is greatly appreciated!

 

[turbosat]

Phlat you are finding out all the things I had to learn when I stuck the 1m primestar on the polar mount a couple of years back. What I found was, all the places I needed extra movement, didn't have enough, so I had to "build it in" lol. If you haven't tried to get any tv on it yet, we don't really know where the problems will be, do we? If you can't get enough declination out of the birdview rig as is, then you have to rig a way to add some wiggle room. One way might be to put longer bolts thru the dish, and run a nut up each one, so it fits between the back of the dish, and the mount so you can lean it up, or lower it down more.
I can make some more pics of my backup system (the primestar on polar mount project) if you like. I ended up with part of a DirecTV Ku/Ka dish's mount on mine. It's monstrous looking, but it works.

 

[phlatwound]

turbo, as you know your P*/polar project was one of the things that inspired me to try this one.

I guess I will try putting the original rx/tx unit on there for my first attempt, if nothing else I need to put it on there to determine where the focal point is, then I can put a more "standard" Ku LNBF on there.

I think I may have close to enough declination as it is, by my calcs if the dish face is at 71 degrees, and the dish offset is 22.6, I should be "looking" at approximately 48 degrees elevation, need to be at about 47 to hit 93W. Just not sure what will happen once I start swinging off of true south with all those angles working.

 

[Cadsulfide]

phlatwound;

An outstanding project! I know you will devise a clever adaptation, looking forward to the pix!

 

[phlatwound]

phlatwound;

An outstanding project! I know you will devise a clever adaptation, looking forward to the pix!

Thanks Cad-s, I hope your confidence is well-placed, thanks for the kudos and here's some more pics.

Installed the big rx-tx unit but got no signal, not even sure if I was hooked up to the right connector on the LNBF. Thought about trying to do a little transmitting on some "unused transponders" while I was at it..............

I did get some measurements while the rx/tx unit was on, and have now placed one of my Techsat Tracker II's on an "Iceberg Special" (less duct tape) block of wood.

I have tilted my elevation bar forward quite a ways to increase my declination, at this point I am just trying to see if I can get a signal on 93W, once I acquire that I will know a lot more about the range of adjustment I have available with the current bracketry.

 

[phlatwound]

Am now viewing a lovely Latin lass on the Azteca mux with 98% SQ, not sure what she is saying but I sure like the way she says it.

I'm still not sure if that rx-tx unit would have worked but I made 3 adjustments to my setup that worked wonders:

1.) Changed my LNB setting from Universal to Standard.

2.) Cut off some overhanging limbs that were right over the top of the dish, wouldn't have bothered a prime focus but they were shading the upturned view of an offset dish.

3.) Inserted a shim made from a Michelob Amber Bock package under the Tracker II LNBF to get it in plane.

Next step, move the elevation bar back to 37.7 degrees and see if I still have enough declination adjustment in the brackets.

 

[phlatwound]

Moved the main elevation tube back to 37.7 degrees and still had plenty of declination before the dish frame hit the mount, with room left for even more downtilt, if required.

The dish is tracking well from 72W-103W, but I think I am having tree issues past that point to the west.

Was planning on not cutting the offending tree until this winter but my chainsaw throttle finger is getting a tad itchy.

 

[turbosat]

Sounds good! For the tree, now that depends on how close it is to houses, power lines, streets, alligator ponds, etc. A plain old pine tree sticking out in the way, hasn't got a chance!

 

[phlatwound]

Sounds good! For the tree, now that depends on how close it is to houses, power lines, streets, alligator ponds, etc. A plain old pine tree sticking out in the way, hasn't got a chance!

This tree is a 60' black walnut, luckily there are no real obstacles in the direction it will want to fall when cut. We don't have any gators in the woods around here, but occasionally we'll run across a rattle-headed copper moccasin.

This has been an interesting experiment, I'm surprised it is working as well as it is so far.

If I can get the all kinks worked out with the 1.2m dish my next effort will be to put a 1.5m or 1.8m offset on this mount.

 

[turbosat]

Hate to kill a black walnut that big, that lumber should be worth something. Got a friend with a sawmill and a truck?

 

[phlatwound]

Hate to kill a black walnut that big, that lumber should be worth something. Got a friend with a sawmill and a truck?

Appreciate the thought, turbo, but this tree was struck by lightning about 20 years ago and it has a huge (healed) gash down the trunk.

It wouldn't even make a good saw log, much less a veneer log. I thought it was dying for a couple years after it got struck but it made quite a recovery.

Black walnuts are thick as hair on a dog's back around here, sold about 100 trees 4 years ago, should have another batch in about 8 years.

 

[Cadsulfide]

Would make for excellent wood turning blanks for those so inclined to spin wood instead of electrons!

 

[phlatwound]

I was able to do some more tweaking today and am now able to pick up everything from 72W to 123W. In that much travel of the arc I've only got about 300 counts with the 8-magnet wheel on the G-box, but am able to return to any sat with acceptable accuracy.

Once I get the slop out of the worm shaft I think I can improve my accuracy even more.

I think that walnut tree is knocking me out on 125, 127 and 129W, but I've got a cure for that.

 

[gremlin411]

You know Phlatwound I never did like that walnut tree anyway.......... LOL!!!

 

[phlatwound]

You know Phlatwound I never did like that walnut tree anyway.......... LOL!!!

gremlin, I think narrowed the culprit down to one limb today, and it's about 6" diam where it needs to be cut off. If it was about half that size I'd take it out with my 12 ga. Remington "saw".

Got about halfway through the arc (72W-123W) testing tps today, will post SQ's on the usual suspects when I get the rest done.

 

[phlatwound]

Here's some Q readings on what I got out of this Frankenstein rig:

72W: NBC mux 97%
74W: ONN 96%
79W: NYN 91%
83W: RTV 67%
85W: Echo Test Card 95%
87W: E! 88%
89W: ABC News Now 90%
91W: LETN 90%
93W: Azteca mux 94%
95W: CCTV 96%
97W: Al Jazeera 95%
99W: AGHAPY 92%
101W: TV English 98%
103W: Beach Cam 91%
105W: Echo Test Card 88%
107.3W: 11918 H 6859 90%
121W: "Dish @ 121W" 95%
123W: 11966 v 20000 69%
125, 127, & 129 = tree-blocked

The receiver was a Coolsat 6000.

Not bad, especially considering I really haven't played with the LNBF location much. Also need to shim the slop out of the worm shaft with a thin washer or two, and put a solid connection in the shaft coupler.

The G-Box works great on this setup, even with only about 300 counts in my usable arc, and the slop in the worm drive, it consistently hit every sat from either direction. I was using the G-box as a stand-alone positioner, and didn't try saving any positions since this was just a temp setup, just noted the count on the display for reference.

 

[turbosat]

Where's the pics of your creation? Inquiring minds, you know.

 

[phlatwound]

Where's the pics of your creation? Inquiring minds, you know.

Having trouble with my camera but here's a few:

 

[turbosat]

I was curious about the back of it phlat, lol. That gives me a pretty good idea of what you did though. Long as its working!

 

[phlatwound]

I was curious about the back of it phlat, lol. That gives me a pretty good idea of what you did though. Long as its working!

Here's some night shots, they actually look better than the day shots I think.

I used self-drilling Teks to attach the pivot bracket angles to the BV mount, I could have them off there, and a BV prime-focus dish installed on that mount in about 15 minutes, with a little help. If I put a larger offset on there in the future I will probably put some weld on there.

I am going to attach a declination adjusting bolt from that upper tab on the dish frame to a bracket on the mount, for now I have just tightened the main pivot bolt and it seemed to hold the adjustment for this experiment.

It was pretty simple to get that rig going, I'll lay out my procedure in another post, soon.