Look what I dug up this weekend - Wildblue dish

[delta_charlie]

Hi all, check out what I dug up. It is a Wildblue dish that measure 28 by 26 inches. Looks to be very well made with adjustable skew and micro elevation. I need to research what the small second reflector does. Not sure what I'm going to do with it yet. Anybody have a side view picture of how the LNB was mounted? Got to run, DC

 

[Anole]

Normally, I understand the dish and hardware are worth some money.
Since your transmitter/receiver are missing, I suppose you could use the dish for other purposes.
Remember, it's sized for use on Ka band, so it's on the small side for Ku.

Not sure if I'd try to mount a Ku LNB so it uses the sub-reflector, or put it out at the actual focal point of the dish (beyond the sub-reflector).

 

[caddata]

It's called a Cassagrain feed. Also used on telescopes and large microwave dishes. Illuminates larger dishes to their fullest extent.

 

[yuccabrevifolia]

DC,

I've had one of these rattling around in the garage from a yard sale last summer. Here is what the LNB looks like mounted. Can get you measurements if you need them

yuccab

 

[upnatm]

I thought I'd share a few pics too, just to help give an idea as to the LNB position.
The last pic is the nearest I've got to a side view.
I had to crop the original. to get the close-up.

I tagged along to help install internet and telephone communications at a mining camp in the northern bush, about 160mi. west of Attawapiskat, Ont.
Hard to believe, but it rained on us in the last week of January up there! Then we saw 3 days of -38c and windy before we left.
I put up the 4 gray dishes, grouped on the left. I think we finally aimed them towards some HughesNet signals in the end.


Hope my ramblings have helped in some way.

 

[turbosat]

upnatm , nice pictures, you should get something for being able to spell that place's name!
What kind of mining do they do up at that place?

 

[delta_charlie]

Hi all, thanks for the great pictures! I can clearly see the mounting screws and can pull the scale from them. Looks like the LNB mounts closer and down a bit from the center of the second reflector. I was playing around with a mirror and some string this morning trying to figure out where the LNB might mount and had it a bit different so the pictures will really help me to get it right. I think I will try to mount a linear Ku LNB on the dish. Should make for an interesting project. PS - I love the pictures of the mining camp. Take care, DC

 

[upnatm]

@ turbosat, heh-heh! I located the place on google-maps, then "copy/paste"! lol.

The camp is exploring for "Chromite", large deposits already found. Biggest chromite deposits
on the N-American continent, apparently.

If interested, google up "Ring of Fire" and "Chromite"

Getting way off topic here, but a few more pics shouldn't hurt, I hope.
(right-click, open in a new tab, zoomable).

1st pic, departing Geraldton Ont.
2nd pic is of a poster showing the camp in summer. (FreeWest was bought up
by a larger group while we were there).
3rd is kitchen (free meals! must've put on 20Lbs! lol). Bev sub on 46" LCD.
Last is the server boxes, for the modems, routers and such, in the "Core-Shack".

Like I said, WAY off topic, I'm out'a here! Cheers!

 

[ACRadio]

It's called a Cassagrain feed. Also used on telescopes and large microwave dishes. Illuminates larger dishes to their fullest extent.

It's a Gregorian feed...or I guess a quasi- Gregorian feed. On a true Gregorian feed the sub reflector will be parabolic instead of flat. Gregorian dishes are used quite a bit in Europe, especially the Fibo brand.

 

[AcWxRadar]

Hi all, thanks for the great pictures! I can clearly see the mounting screws and can pull the scale from them. Looks like the LNB mounts closer and down a bit from the center of the second reflector. I was playing around with a mirror and some string this morning trying to figure out where the LNB might mount and had it a bit different so the pictures will really help me to get it right. I think I will try to mount a linear Ku LNB on the dish. Should make for an interesting project. PS - I love the pictures of the mining camp. Take care, DC

Charlie,

Just for an item of interest....

The original "LNB" that is supposed to be installed on the WB dish is referred to as the TRIA (Transmit Receive Isolation Assembly). It operates as a circular polarized device in the Ka frequency band. The dish reflector can be made smaller due to the higher frequency band.

As for the value of your find, I am not too sure how much demand there is for the dish alone (to WB customers). It is the TRIA that is highly valuable, if it is operational.

It has been a long time, but if I recall correctly, a new (outright purchase) of the dish and TRIA assembly was around $700+ or so. I may be wrong, but that figure sticks in my mind.

Thought you might be interested just to know a little miscellaneous info about it.

RADAR

 

[Stargazer]

I scored two of these this year with the lnb's and one over a year ago without the lnb. I was told that the two with the lnb's are two different types (I think for different satellites). I was also given a modem but WildBlue tells me that none of the used ones can be activated and that you have to get new stuff. I called twice and that is what they tell me.

 

[caddata]

.....It's a Gregorian feed...or I guess a quasi- Gregorian feed......QUOTE]

You're correct AC, a closer look shows both reflectors to be concave. Where as, a Cassagrain uses a hyperbola (convex or inverse parabola) sub-reflector.

 

[delta_charlie]

.....It's a Gregorian feed...or I guess a quasi- Gregorian feed......QUOTE]

You're correct AC, a closer look shows both reflectors to be concave. Where as, a Cassagrain uses a hyperbola (convex or inverse parabola) sub-reflector.

Hi Caddata and the group, I checked the second small reflector with a straight edge and found it is flat. Not concave or convex. I was thinking about what the second small reflector might do other then make the dish assembly shorter and I think it might have something to do with bringing the collected microwaves into a sharper focus from the top and bottom of the dish. Think of it this way - the distance from the top of the dish to the center of the LNB compared to the distance from the bottom to the center of the LNB would be longer from the top on a normal offset dish without the second reflector. When you are talking about microwaves as short as Ka then it may well be making a difference in how well the dish can focus the microwaves. In any case it is an interesting dish and fun to tinker with. Got to run, DC

 

[caddata]

I experimented with a Cassagrain subreflector on a 10' FRP dish in 1983. Geometry and instructions were supplied by Butch Simpson, in one of his experimenter's guides. Butch worked for HP in Greeley, CO for his day job and sold experimental TVRO kits as a hobby. Several of his circuits were incorporated into some of the first C Band receivers sold to the public. My first C Band receiver was one of his kits.

You can establish the final F/D ratio with the sub reflector so I chose .7 for mine--the dish was .375--a real deep dish which was hard to illuminate without a buying one of the hard to find and costly Corotor feeds. The .7 F/D allowed the simplest feedhorn fabrication. It was fabricated from copper sheetmetal, pyramidal in shape, bolted to the LNA, and both were rotated with an over-the-air T.V. rotor for horizontal and vertical selection. I used a Radio Shack (Realistic)---others were using Channelmasters. He supplied graphs that told you the sizes and shapes for the subreflector and feedhorn.

The subreflector was a cone about 8" in diameter x .875" high, mounted near the focal point of the prime focus dish, and fabricated from aluminum sheetmetal. The point of the cone pointed down towards the center of the dish and the feedhorn pointed upwards toward it. Keeping rain out of the feed was a problem. I used it for several months, until I could afford one of those expensive first generation Corotors.

 

[delta_charlie]

Update - got LNB mounted and set mast.

Hi all, I think I have the Ku LNB mounted close to where it needs to be. It was really quite simple to mount it, just used a universal LNB holder and a couple of pieces of aluminium flat stock. Have it clamped in place now so I can move it if needed. Hope to try and find something strong like 3ABN to fine tune it. Just set the mast this morning and after the concrete sets will give it a go. Should be interesting. Later, DC

 

[delta_charlie]

Update - could not get it to work, bummer!

Hi all, well I gave it my best effort but I could not get the Wildblue dish to work on Ku. I tried using the second reflector and then removing it and placing the LNB at the true focal point and simply could not get good signal Q. I found 3ABN quickly with my initial setup but the signal Q was far to low. I moved the LNB by hand to try and find the sweet spot but there did not seem to be one. Looks like the dish is simply not compatible with the Ku LNB I used. Oh well, not all is lost as I now have a very strong and stiff Sch 40 2 inch pipe in a spot in the back yard that will make a great Ku motor mount. My current motor is up against a growing tree at 105W. The new spot can see past 127W so I plan to move the motor some time in the future. Looks like the Wildblue dish will get listed on craigslist and or ebay. Maybe it can fetch enough to help offset the cost of a new 90 CM dish or motor. Later, DC

 

[Pixl]

DC,

Thanks for posting the results, or lack of results. I had been offered one of these Wildblue dish for free here in Michigan and thought about the same mod. You saved me a lot of trouble, I think I'll pass on it.

Jim

 

[ynnedibanez]

got ku with this, with a standard ku lnb in the middle of the scalar ring but never locked c-band
http://www.satelliteguys.us/c-band-satellite-discussion/202884-my-minibud-experiment.html