7.5' Aluminum dish

[el bandido]

The side view in post 5 does not look that deep.

[rrob311]

It's 90" in diameter and 20" deep. From what I have gathered the depth is about the same as the Winegard Pinnacle dishes which I have heard good things about.

hxxp://www.satlex.de/en/fdratio.html

[el bandido]

I do not know what the thread pitch or the diameter is on the Invacom piece. You may need to add a few more threads for best reception. Install it and see what you get first. If you screw the scaler ring all the way in and the signal is still climbing then you probably need to add a few more threads.

[rrob311]

I misplaced my feedhorn and have been searching for it today. I don't know if the diameter of the threaded part stays the same to where its not threaded. If it is I can order a die to make more threads. Otherwise I will have to grind it off I suppose. I have a Norsat 4508a I would like to try out along with an Inverto quad

[el bandido]

I just looked at mine. Not much of a way to add more threads to it. It will be a challenge to get lnb parts that are a precise match for a dish that deep.

[rrob311]

It looks like Chaparral sold a "golden ring" which extends the throat of the lnb slightly to allow f/d ratio adjustment from .28-.33. If I can obtain a spacer that fits the front of the adf-120 I should be able to maximize the reception on this dish. I think I only need a few millimeters of extension.

[dr.zin]

I remember the ring from an lna I bought in the 80's but never had a chance to use.
Would that be something I need on a modern lnb/ 8.5' dish?

[rrob311]

If the f/d ratio is less than like .32 you would want to use it. Feeds that support a lower f/d ratio are hard to find. Do you know what the f/d is on your 8.5' dish?

[dr.zin]

I didn't get the dish yet,I was just wondering for when the time comes.
Spun aluminum 8.5'

[rrob311]

Here is a calculator for determining f/d:


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