Hook DIRECTTV TO C-BAND DISH ?

[PATONENOW]

I have 3 big dishes and like to experiment sometimes. Two are 8' mesh and one is 10' solid dish. Anyway I was thinking of using the DIRECTTV equipment on my big dish (solid) to experiment with rain fade and signals. I figure it will work but not quite sure of the right focal distance. I certainly don't want to "overdrive" the receiver and hurt it. I would guess others have tried it and any suggestions would be appreciated.
Always wondered why they didn't make a set-up that would compress the signals as that would sort of do away with moving the satellite dish so much ( sort of a semi-all around lnb or lnbf.
But that would take the fun out of finding new things out there.

 

[truckracer]

directv on bigdish

The big dish is certainly capable of very very reliable dbs signals if:

The dish is solid metal, not fiberglass-fiberglass has screen mesh inside that decays quickly in old dishes plus the mesh is spaced too far apart for ku band in most cases.

A mesh dish will work as long as you cannot pass a pencil through the mesh. or holes are .032".

You must have a circular polarized dbs lnbf on the dish.

Feedhorns are available with a dbs lnbf.
I like the feedhorns that have an outlet in the feedhorn for the dbs lnbf.
(Not the one that goes in the side of the scalar ring). These probably work ok,
but they are not at the exact focal point of the dish.

You may be able to rig a D* lnbf with some homemade brackets on the dish if it is only going to be used for dbs.

My 7.5' sami peggs out the signal meter on my D* receiver.

I don't think you can physically hurt the receiver by strong signals except that signal overdrive could cause reception problems if it was severe enough.

Good Luck and have fun.

 

[truckracer]

Aslo although a D* lnbf is designed for an offset dish, i have used them on prime focus dishes with excellent results. I am using a KU linear lnbf on my 7.5' mesh,
that will get 90% signal quality on the 11720V transponder on G10R. So it must be pretty close to accurate, that's a hard one on a small dish for Free to air.

Using a fortec ultra lifetime

 

[PATONENOW]

Thanks,truckracer. My dish is a solid aluminum one going on 23 years and still holding up strong. I will try some of those things.(Remember back when everything was free and the talk show hosts said things and next day were surprised to hear that when they thought they were off the air we could still get them?!)

 

[dfergie]

to SatelliteGuys...PATONENOW

 

[truckracer]

directv on big dish

solid aluminum is a great dish, kind of wish i had one. speaking of compression, always remember we don't want anymore compression than necessary since compression causes picture and audio quality to greatly decrease on digital signals.

This is why picture quality and audio is so much cleaner on c-band. There's no signal like the first generation master broadcast quality coming straight into your home from the big dish.

The small dish folks use c-band dishes to receive their programming and then encrypt and reuplink on ku band to their own satellites and small dishes. They compress the daylights out of it so they can fit 150 or so channels on one satellite.

This is where you get the washed out color and fuzzy vision pictures.

 

[iammike]

My dish is a solid aluminum one going on 23 years and still holding up strong.

Sounds a lot like the dish I rescued last summer. Mine is bent , warped a little, only somewhere between 7.5 and 8 feet wide and I still get signals comparable to a lot of folks 10 foot dishes.

 

[norman]

I wonder if you could do the same for dish using the 2 lnb setup? Can you over drive the signal input???? Satellite minds want to know.

 

[PATONENOW]

NORMAN,I plan to do more testing this SPRING ( about MAY) and will let know when finished. Figure I would start with long focal distance and slowly increase it figuring I would be using the 3 lnbf directtv and not the 15` degree c-band lnb which is 39" focal length. Always fun to experiment(long as nothing blows up).

 

[trscott]

Mesh size for Ku?

"A mesh dish will work as long as you cannot pass a pencil through the mesh. or holes are .032"."

A bit of a discrepancy here...

I should hope that a pencil wouldn't pass through a hole that is 1/32 of an inch!

Did you maybe mean 0.32"?

Actually I am curious because I have upgraded from C-only to C/Ku with high-quality Norsat upgraded LNBs for both bands, but still not entirely satisfied with the signal quality of my Ku. I am getting by with pretty good signals on X4, but not as much signal quality margin as I would like.

My 12' dish has aluminum expanded metal mesh with diamond shaped holes that will pass a 0.156" drill, but not a 0.188" (5/32" and 3/16").

I tweaked the centering of the feedhorn, and its perpendicularity to the dish center, but now I am about to try some fine mesh window screen to see how much improvement that will make.

Anyone want to speculate about how much improvement I will get?

I bought a 24' roll of aluminum window screen this week and plan to begin by temporarily covering a percentage of the dish surface, may be 1/4 or 1/3 of the total area. So if I currently see TCM with 100/80 am I going to see an improvement to 100/85? Or 100/90? Or maybe even 100/100?

The other problem I have is a bit of fade where the signal will jump around. I suppose that is noise from some source.