Using Dish 500 for Ku linear FTA

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tvropro

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Mar 9, 2007
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I am in the process of getting a bracket made to adapt a linear Ku LNBF to a dish 500 dish I have. I want to point it a possibly 72 degrees west and get some channels. For those who have messed with mini ku dished on linear what are the best satellites to get at least the stronger channels on? Has anyone ever tried G-19 on a 20 inch reflector?
 
When I tried an 18" non-skewed dish on G19, I got about 6 transponders reliably, unless it was raining.

I tried it on 72W and it worked pretty well for a while, then somehow it got out of alignment and I could never get it back the way it was. It always seemed like I could get either the permanent channels or the feeds, but not both at once. It didn't even seem to follow a horizontal/vertical pattern like it did on G19, which is weird because 72W is a lot closer to south for me than G19. Maybe with a 20" skewable dish you'd get better results.

74W took me forever to find, but once I did it's been strong ever since. Ohio News is only average strength, but some of the feeds max out the meter. I think my problem with finding it, and probably with peaking 72W too, could be because there are so many strong satellites so close together here with all the DBS birds.

I can get Telemundo fine on 79W, but no feeds, although I didn't spend a lot of time waiting for feeds.

On 101W I got almost all the transponders. I probably could've got more but I didn't spend a lot of time on it since it was winter at that point.
 
When I was testing out the Geosatpro DVR-1100c circa Jan. 2009, I used a 24" Dish Network dish on 97W.
The dish was warped at the time- not that I knew- but it still worked well enough on the brand-new Galaxy 19 to pull in a few transponders especially in better weather
MHz Worldwide when it was on 11789 V
Russia Today on 12152 H
Al Jezeera on (where ever it was at the time on V, but not on the same transponder as RT)
If it was not raining
, I could listen to Access America on 12115 V

I had to pick between RT and Al Jezeera which one came in. But peaking Al Jezeera got me the best signal Quality.

As you know they have messed with the power levels of each transponder since then.
 
This modded Hughes dish could bet G19 on a good day but suffered badly with rain fade
 

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G-19 could prove interesting since I would like to get Russia Today, the PIT channel and Access America again. They have been gone since I swapped out my ADTH for 103 (feeds :)) and 107 (Shaw) now. I took a site survey and where I want to put it I can see from about 93w to way east. If I go any further west I hit my house.

What transponder is really hot on G-19 so I can find the bird?
 
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I would skew the dish itself if you can.

97W is only 4 off my true south (93) so minimal skew but Chicago your true south is what 87? Thats more skew you would need
 
Ice what will skewing the dish obtain? Im only using one lnbf at boresight. I thought that you need to skew the dish only if you had multiple feeds to compensate for the inline of the lnb's. I guess I could skew the dish to the right (looking behind the dish) since I will be west of true south. Maybe start at center and then add tilt. Maybe someone can explain skewing in depth to me.
 
Normally you would skew the LNB but I've learned if you can skew the dish then do it that way. You get a little more signal that way since the LNB is reflecting into the whole dish.

I had an old DirecPC dish that only the dish skewed. The LNB was bolted to the dish and could not be skewed
 
Okay now I grasp it... what you want to do is set the lnb at 0 and skew the whole dish to get that lnb skew. Neat :D

Im hoping to maybe mess with it this weekend if the bracket gets done and the weather is in the 40's like there saying and the rain holds out. We will see what happens.

Thanks Ice :)
 
Hi all, there is a nice adjustable LNB bracket available for less then $10.00 Check out an old post with lot's of pictures of the bracket and a Dish 500 at: http://www.satelliteguys.us/free-ai...35-mood-make-something-linear-dish-500-a.html One of the things I noticed when I played around with the little dish is I would loose about 10 points on the signal Q when I set it up for horizontal polarity and tried to tune in a vertical TP. In order to get the last little bit of gain out of the little dish I found I had to move the dish 90 degrees from where it should be and move the LNB 90 degrees. Apparently there is a sweat spot across the dish and it looses a bit of gain from top to bottom. Your results may very but do not be surprised if you can not lock both polarities without re-skewing the dish. Hope this helps, DC
 
Delta_charlie and phlatwound, those are clever setups and delta's swivel AZ adjust' is pretty nifty. I've experimented quite a bit with small dish linear feeds and I found the sweet spot to be further away from the reflector, both of your's show they are closer F/D than what I've determined in my testings.

How did you both determine the F/D?
 
LNBF holder done

Here is the finished LNBF holder. Now to put the dish up. :)
 

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well researched; recent examples:

Required reading:

The link Delta_Charlie gave above.
First rate info and examples.

Then, this thread for getting Azteca is worth looking through, but at least read these two posts by me and look at their links!:
http://www.satelliteguys.us/free-ai...-93-1-dish-500-sucess-pics-2.html#post2024744
http://www.satelliteguys.us/free-ai...-93-1-dish-500-sucess-pics-4.html#post2041920

Today, I'd just get a recycled DirecTV Phase III dish (they're as common as Dish 500's!).
Then, stick this LNB on it (mounts without any fuss nor bracketry).
Skew the dish and be done with it! - :up
 
McGuyver, do you mean focal distance?

If so, I just took some measurements of the placement of the stock DSS LNBF before I removed it and tried to replicate those with the placement of the linear unit.

Hi phlatwound, yes, the focal distance. If I recall correctly, the measurement for the F/D should be 13-1/8" distance from the center of the dish to the actual front edge of the feedhorn, this does not include the plastic cover so in order to measure correctly you sometimes need to pop the cover off. This is the optimum focal distance for a Dish 500 reflector. The offset angle is also critical and in my experience it's hard to get it right even by taking measurements of the stock LNBF, I never have been able to get it replicated precisely using the comparison method. This is why I use the long feed arms from DirecTV dishes because they are the proper length and proper offset angle and will perfectly adapt a linear rectangular mount LNBF. Now if you use other LNBF's with only a throat mount then you'll have to do it as you have and do your best to get it right. I've experimented with various types of linear LNBF's and it seems that not all liked the same position. Mounting the LNBF slighlty off specs will definately hinder the signal and performance when shooting for linear birds on a small dish. Improper placement will also effect the elevation scale. This could be why some people can get stronger signals on one polarity and not the other.
 
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