New user - old Birdview

[telstar_1]

I think he's thinking you don't have a usable scalar, but it looks like you do- like the feed & electronics simply unfasten and slip out of it. It's usable & needed, however, just for C-band, unless going to a C or C-Ku feed with its own scalar. If doing Ku only, then removing it altogether, if possible, is best. A Ku LNBF could be used either with or without a (smaller) scalar.

Perhaps he doesn't realize (per pics in thread) that this dish is already pole mounted- long ago.

"Stringing" is the old-school way to check for dish deformation. Pull string or wire taut across dia. (face) of dish at 2 or 3 circumferential locations. The strings should just touch each other at the center without pressure on one another to indicate a non-warped reflector. Yours probably isn't significantly warped unless maybe a tractor ran into it or something. Birdviews are pretty strong.

A declination adjustment, if added, would go where the top azimuth pivot is. It would allow to lengthen/shorten the top anchorage of the main pivot. Its purpose is to keep the dish's focus on the geo arc throughout its azimuth travel. Your dish is likely reasonably usable as-is for some multi-position use. If looking for single-sat reception, at least at first, just go find it by moving the dish on its pivot (as like when the arm extends/retracts) and then checking whether an elevation adjustment (main up/down securing bolt) yields any stronger signal. You don't need any declination fine-tuning for single-position reception.

 

[bombu]

I think he's thinking you don't have a usable scalar, but it looks like you do- like the feed & electronics simply unfasten and slip out of it. It's usable & needed, however, just for C-band, unless going to a C or C-Ku feed with its own scalar. If doing Ku only, then removing it altogether, if possible, is best. A Ku LNBF could be used either with or without a (smaller) scalar.

Perhaps he doesn't realize (per pics in thread) that this dish is already pole mounted- long ago.

"Stringing" is the old-school way to check for dish deformation. Pull string or wire taut across dia. (face) of dish at 2 or 3 circumferential locations. The strings should just touch each other at the center without pressure on one another to indicate a non-warped reflector. Yours probably isn't significantly warped unless maybe a tractor ran into it or something. Birdviews are pretty strong.

A declination adjustment, if added, would go where the top azimuth pivot is. It would allow to lengthen/shorten the top anchorage of the main pivot. Its purpose is to keep the dish's focus on the geo arc throughout its azimuth travel. Your dish is likely reasonably usable as-is for some multi-position use. If looking for single-sat reception, at least at first, just go find it by moving the dish on its pivot (as like when the arm extends/retracts) and then checking whether an elevation adjustment (main up/down securing bolt) yields any stronger signal. You don't need any declination fine-tuning for single-position reception.

 

[bombu]

Here's a photo of the scalar without the feed horn, etc.

We can see that the six legs of the support arms pass through and are fastened with nuts. The unthreaded rods on the back of the scalar are a bit bigger so there's only the nuts in front.

The four bolts in the center just clamped the old feed horn in place.

 

[bombu]

https://www.satelliteguys.us/xen/attachments/04-scalar-adapter-jpg.69400/ Shows how Pendragon proceeded (in the thread that I was directed to earlier)

He ground off the ridges in the scalar and attached a cannibalised part from a modern assembly (after reaming the old scalar and extending the mounting arms) which allowed him to mount the modern LNBF in the conventional manner.

It looks nice.

 

[telstar_1]

That should serve as a proper focal point as long as whatever you're using doesn't have to extend too far toward the dish (over 3") from the mount plate.

 

[primestar31]

https://www.satelliteguys.us/xen/attachments/04-scalar-adapter-jpg.69400/ Shows how Pendragon proceeded (in the thread that I was directed to earlier)

He ground off the ridges in the scalar and attached a cannibalised part from a modern assembly (after reaming the old scalar and extending the mounting arms) which allowed him to mount the modern LNBF in the conventional manner.

It looks nice.

Pendragon really knows his stuff, and has quite the advanced skills when it comes to FTA stuff like this. You can't go wrong reading his threads.

Here's the one referred to in the first post, I converted the link to the new forum style to make it easy to find.

P

Thread 'Birdview motor and pole questions'

Aug 20, 2011

I'm looking at picking up a 8.5' solid Birdview. However it would be a good drive there and back. The owner has been quite helpful in supplying information, but I still have a few questions for those who already have one.

1. The pole size is 6" OD, which I have heard before. As the nearest steel pipe OD dimensions are 5.56 and 6.63", I'm curious what others have used. Would it be better to scavenge the tube a la Anole? Maybe I should cut it off at the ground and weld it onto something else.

2. Does anyone know what the maximum motor angles a Birdview motor can achieve? The scans of...

• pendragon
• Replies: 16
• Forum: C-BAND Satellite Discussion

 

[telstar_1]

That was the only dish I knew of that used that fat pole. A 4" sched. 40 would have been well sufficient, especially since it didn't extend that far out of ground, but this was birdview...

 

[arlo]

Arlo, I'm sure you're correct but the dish is going to have to stay where it is for now and I'll just have to live with any deformation. I have more pressing work to do in finishing my new house.

Guns loaded, ducks in a row. It looks like a back burner project and your questions are good.
Any deformation of the reflector is going to hurt the maximum possible signal reception. So you want it in as good condition as possible.
A good bleaching with a brush and pressure washer to make defects more apparent. That's what I'd do.
Get your house done. At least you should know your angles and stuff. Noobs sometimes want it all with little clue of what's involved.

By "ready for a pole" are you referring to replacing the six struts that support the LNB?

Sort of. I meant a pole in the ground and cemented and plumb all the way around. It will make the dish assy. more manageable.
There are quite a few ways to get struts to support the scalar/lnbf. If the links that the other guys can give good ideas for work. Cool.
Sorry. I take some things for granted because although I suck at carpentry. You know. TGFYT....thank God for YouTube.
Having the resources at hand to fabricate stuff with a bit of thought. Make it work. Then make it pretty. Unless your'e building a house.Then it's (I think with a stern comment from the super) NO DAP!

I doubt the dish will ever be motorized enough to use the modern automated computer based control systems. When I get around to disassembling, cleaning and lubricating the jack system I expect to reuse the antique motor controller from the original installation, if I can find it.

Doesn't have to be. You could go caveman and use a trailer ball hitch jack. A protractor glued to the dish pivot point. A pointer. And do it like we used to back when home TVRO boomed. Lots of "antique" controllers on eBay for cheap. IF you can get the the "jack" (actuator we call it).
freed up, the motor cleaned and refurbed, and the gearbox is in good shape. If I can do it. You can do it. Okay. Look on Ricks for a recent post where help was offered to a seemingly 16 year old who ended up throwing his arms in the air and reverted to playing his Les Paul Axe.

In the meantime I'll be satisfied if I can invest a few hours and a couple hundred bucks in it and get some reception from a single satellite. For now I don't really care too much what programming I can receive; it's really just for fun and my education.

You might be surprised. A hundred bucks? A buck-fitty? A single satellite once setup should be a breeze. Getting the mount to track two or 3 sats reasonably. Provided that they are close together in the arc. Not that hard. If you like it. It can get rather addicting.
tube.
W/O going on a tangent. Declination is simply tilting the dish only after the polar angle is set properly and accurately. With the face of the dish parallel vertically with the polar angle. The pivots of the dish. If left that way. The dish will be shooting out in space over the equator.
Satellites are over the equator. So, you lower just the dish several degrees from tables, online setup aids.
Bolts? Spacers? Bolts and jam nuts? Not too hard to figure out a solution.
if not clear, I can dig up a few graphics.

I wouldn't drill a ku scalar to fit the O.D. of a c band lnbf. Scalars are not expensive for ones that will work. Besides microwaves not liking things not dimensionally correct. Your pics lead me to believe that the lnbf is not movable in and out/CW & CCW separate from the scalar.
For c band you will definitely need that. A c band scalar will have 3 bolts to fix the lnbf where it peaks signal the best.

Once the dish is clean. Maybe with a spray of quick wax and a buff. Face flat on a driveway and a look to see if there are any bashed in spots or wavy petals. You should be at least marginally good. Things a teacher might know about a parabola and how intersections work on them.
A flashlight at night and a walk around looking for equal reflections?

And I am definitely learning lots!

Brian,
Is "adding declination" you mentioned referring to a more sophisticated system for moving between satellites?

Do you think the original scalar is likely well matched to this dish or with the looser tolerances of the past is it likely to have room for improvement? I'll unbolt the scalar and take some more pictures.

The dish was certainly installed in the early '80s. Now that I've retired from my school job I now longer have access to a handheld 3d scanner which would have determined how well the dish matched a parabola. I could still laser cut a template to place in the dish and see how accurate the parabola is but I'd need a formula for what parabola to use.