Need help modifying Dish 500 for FTA

[Bob2011]

I am trying to modify a Dish 500 for FTA and I don't have the original LNB so I am having trouble finding the focal point. There are several threads that show success with this dish but no one ever gave measurements for mounting a LNB in the right position. One talked about 13.25 inches from a point 3/4 of an inch below the center of the dish but that didn't work. I was hoping someone had measurements from the top, bottom and side edges to the center of the face of the FTA LNB.

 

[joeroscoe1957]

Bob , hope I can help . From past experience , I can only offer my crude but sucessful technic's . The suggested measurements you mentioned should be close enough to pull in a test patern or info ID channel (what ever is in the clear) from an echostar bird , then adjust the lnb distance and postion for best signal reception . That small of dish is limited to only the strong TP's on the true FTA sat's , so I had to re-tweak the lnb after that . I did watch fta tv . Have fun & best of luck , Joe

 

[mikelib]

I am trying to modify a Dish 500 for FTA and I don't have the original LNB so I am having trouble finding the focal point. There are several threads that show success with this dish but no one ever gave measurements for mounting a LNB in the right position. One talked about 13.25 inches from a point 3/4 of an inch below the center of the dish but that didn't work. I was hoping someone had measurements from the top, bottom and side edges to the center of the face of the FTA LNB.

Bob,
If you are going to use the standard 40mm KU mounting bracket and linear LNB that the vendors supply, you can bolt it to the arm of the 500 Dish. Drill 3 holes starting a 1/4 inch from the LNB end of the dish arm. Make the holes around a 1/4 inch apart. Mount the bracket in the middle hole. The LNB should be pointing to just below the center of the dish. You will get a signal from a strong TP.

I had used this set up for over a year, I had the dish mounted on a board with a lazy Susan and I would take it in and out of my garage to use. I had very good success using this method, my most south sat is at 74W, but I use the mux on 72W and get a very good signal quality. I have the dish stored in the attic for now as I am using a little larger dish, but if you need a picture I can get it for you some time this weekend.

I wish you success with the project.
mikelib

 

[Anole]

real numbers

Distance from dish rim to center between LNBFs:
Top: 20"
bottom: 12"
center of side: 15½"
Understand these four measurements should all converge at a single point, the center of your LNBF.
They may not, due to a number of factors dealing with accuracy of measurement.

Once you are up 'n running, what I recommend is that you get the signal from your true south bird, then reset the elevation on the dish mount to reflect the "correct number", then raise/lower the LNBF to peak the signal.

Naturally, a little in 'n out tuning for focus is wise also.
However, at least you'll be close to start.- :up

As others have commented, a Dish 500 is too small for serious work.
However, having said that, I rigged a DirecTV Phase III for a similar silly test.
Mounting the LNBF to the DirecTV was a lot easier than using a Dish 500, too.
I had both to use, and chose the easier of the two.


old reference material:
----------------------
Anole on finding focal point of unknown dish:
http://www.satelliteguys.us/free-air-fta-discussion/138907-fathers-day-trip.html#post1406345

Template trick to locate new LNB at the proper focus, when replacing it:
http://www.satelliteguys.us/free-ai...ert-superdish-true-fta-use-2.html#post1540313

 

[tamuin]

I read a posting a while back where the person had cut up a rear view mirror repair kit (essentially a flexible sheet that is a mirror on one side and adhesive on the other) and stuck pieces of it on his dish. Then he pointed his dish at the sun and the focus point was the point at which the reflected dots of light lined up, if I recall correctly he mocked up a LNB out of piece of wood, but I think you could use a real LNB.

 

[SatelliteAV]

I read a posting a while back where the person had cut up a rear view mirror repair kit (essentially a flexible sheet that is a mirror on one side and adhesive on the other) and stuck pieces of it on his dish. Then he pointed his dish at the sun and the focus point was the point at which the reflected dots of light lined up, if I recall correctly he mocked up a LNB out of piece of wood, but I think you could use a real LNB.

The rest of the story....... Unfortunately the wood burst into flames threatening to burn down the house. The op burned his hand while trying to extinguish the fire, stumbled into the intense beam of light, fried his retinas and fell off of the roof, breaking both legs........

But really, I do not think that it is a good idea to make a mirror of the reflector in conjunction with the sun. The sun is very powerful and the op could be severely burned or blinded. Maybe a flashlight 20 or so feet away at night reflected from the reflector surface would be a safer and more sane idea?

 

[Bob2011]

I appreciate all the input but I'm embarrassed to say I spent 5 hours and only saw a brief lock on one transponder before losing it. The strange thing is I was pointed at what I thought was 89w but 11991 is on 97w.

Anole your distances make the LNB look like its in the right position but I'm not sure what is wrong. I cut cardboard strips to length and taped them to the dish plus taped them together in the middle to the face of the LNB. My holder was just a bent strip of thin metal so there was some wobble to the LNB. Maybe that was the problem and their is no room for error here.

Mikelib I would be interested in any measurements from your dish as I tried to get the NBC mux but nothing there either. I was thinking of ordering this bracket Universal Single Dish LNB Bracket! LNB Holder LNB Mount | eBay but I think there is still the issue with the short LNB arm on the Dish 500.

I think I will keep my eye out for a free Directv dish and see how that works out. The whole idea for this project was to have a neighbor friendly dish close to the house for experimenting and to leave the 4 footer in the backyard locked on one satellite.

 

[Anole]

size really matters

Oh, don't get me wrong.
The DirecTV Phase III dish sucks, too.

What you really need, is a dish a lot wider!
(and a feedhorn to match the shape of the dish)

Here are some readily available dishes to talk about, think about, look for, etc:

DishNetwork Superdish and DirecTV dishes:

DishNet SuperDish: 36" x 20" h
DishNet D-500:... 20.5 x 22" h
DirecTV Slimline: 32.5 x 22.5 h
DirecTV Phase III 20.5 x 18.5 h

Point is, those are still going to perform badly, as you won't have a suitable feedhorn to match the dish.
That's why we (I) recommend a 36" round dish (or bigger), to everyone.

edit:
Okay, here are some sizes of popular Primestar and later Andrew / Channel Master dishes.
They all have matching feedhorns, including the odd elliptical ones.

Primestar / ChannelMaster dish info:
size, . . width x height
1.2m = 48x52 round
1.0m = 40x43 round
84e is 40x30
75e is 37x27
70e ?? 35x21
60e is 32x20

Go scare up one of these, if you're looking for a freebie antenna out in the wild.

 

[jasjas]

I would try this lnb from here.
http://www.satelliteguys.us/free-air-fta-discussion/256389-customer-email-about-esx521-ku-band.html
has good gain

 

[hwm]

The LNB arm on the Dish500 is too short. You need to extend it for use with the "universal LNB holder" sold on eBay. I am able to get most transponders on 97w and 101w during clear weather with this dish using a cheap ROC branded linear Ku LNBF.

These pictures show the placement of the universal LNB holder on my modified Dish500.


I posted a thread with plenty of photos here a while back on my Dish500 with linear LNB project. Bottom line is: good weather and strong transponders only. But still a fun and somewhat useful project.

 

[Pixl]

I think I will keep my eye out for a free Directv dish and see how that works out.

Bob,

An easy way to find these dishes for free is to post on "FREE CYCLE". There is one in Albany if that is your area.
http://groups.freecycle.org/AlbanyFreecycle/posts/all
Or find a Free Cycle group near you at The Freecycle Network
Free Cycle lets you post for things you need or want to give away, but they have to be absolutely free.

Here is an ad I posted and easily got four dishes in a few days.

Wanted: Old Outdated Satellite Dish (TC and area)
Large or small satellite dish wanted for radio hobby. Even an old Prime star dish would work for my project. I can dismantle and remove if still in place. Thank You.

By the way how is your 1.2m dish working for you? Did you get the original lnb to work?

 

[GenBap]

I posted a thread with plenty of photos here a while back on my Dish500 with linear LNB project. Bottom line is: good weather and strong transponders only. But still a fun and somewhat useful project.

I think this is the thread here . Right now I am getting a 66 on 125 W but not picking up all transponders. I placed the LNB at the end of the dish 500 arm. Looks like my Memorial Day weekend project my be to get that in a little stronger by following this directions. Thanks hwm.

 

[turbosat]

Interesting project for 125. I never tried my DN dish on 125, but it did ok on AMC1 and Gal17. In good weather, the little thing really surprised me, comparing wildfeeds on 91 with a 1m dish, at the same time, seems like it was getting about 8 out of 10feeds the bigger dish did. In the rain though, I never got to try it out. A desperate person in an apartment could use one to get a lot of tv , lol.

 

[Anole]

Turbo-500

Kudos to Turbosat.
His picture on page two of this thread, shows that a simple metal bracket and a conduit hanger are all it takes! :up

But, look/read through the entire thread for several more amazing ideas and thought-provoking pictures ! -

 

[Bob2011]

The LNB arm on the Dish500 is too short. You need to extend it for use with the "universal LNB holder" sold on eBay. I am able to get most transponders on 97w and 101w during clear weather with this dish using a cheap ROC branded linear Ku LNBF.

These pictures show the placement of the universal LNB holder on my modified Dish500.
View attachment 65967View attachment 65968

I posted a thread with plenty of photos here a while back on my Dish500 with linear LNB project. Bottom line is: good weather and strong transponders only. But still a fun and somewhat useful project.

WOW thanks HWM : ! Your measurements worked ! The ruler in the photo helped me get the right angle to bend my holder back into place. I will be buying that holder off of ebay for sure.

Another issue I discovered is that at some point I turned off the 22 Khz tone for the universal LNB. This is my first time using one so I wasn't too sure about it. So I'm sure at some point the other day I could have locked on a signal but I had the settings wrong :doh:

The most surprising thing to me is how I found 97w. I was scanning and getting no Q then it stops on 11911 and shows 95 on both S and Q( this is on a CNX Nano box). This appears to be some strong data transponder. So at that point I tweaked the dish a little and the Q came up on some of the other transponders. The best one was 11874 with Q of around 90 and a few others were in the 80s. No RT or KTV 2 though.

I will find a permanent spot for this dish and get a new holder over the next week and let you guys know how its working out. Just from the channels I locked in on 97 it makes it a worthwhile project to me. Once its all mounted properly my cost is less than $20.

Thanks again for all the help everyone!

 

[turbosat]

Sounds good Bob, it seems like I recall scanning in about 110 channels on 97W, when I tried with my little dish. But the one I used was the dishpro dish, I think it is an inch or two bigger than the old Dish500 dish. Either way, they're mostly too small for anything except playing, but it is fun to tinker around with on a not-so-hot day. I know the Pentagon channel was booming on mine when I tried it, that was one of the main reasons I had gotten into that anyway.

 

[GenBap]

After applying the proper measurements I was able to move my Q from 69 to 87 on 125 W but still only get the transponder with Create and World on it, which is what I am after anyway. Going to ask my neighbor for the Dish 500 they are not using and add it to pick up Pentagon. Can't hardly wait!

Interesting project for 125. I never tried my DN dish on 125, but it did ok on AMC1 and Gal17. In good weather, the little thing really surprised me, comparing wildfeeds on 91 with a 1m dish, at the same time, seems like it was getting about 8 out of 10feeds the bigger dish did. In the rain though, I never got to try it out. A desperate person in an apartment could use one to get a lot of tv , lol.

 

[GenBap]

Encouraged by yesterdays results with 125W, I decided to ask my neighbor for their old Dish 500. I watch 101W often but it was to the right of center on my multi-lnb dish (standing in front of the dish) and I was experiencing some fade in the evenings and night with a Q of about 66 on the Coolsat. After moving the transponder to the Dish 500 I was able to get a Q of 87 on History and Bio and 91 on BVN. A good improvement. I probably could get that on the large dish but due to the construction of the dish and center being on 97W I was never really able to get the kind of reception I wanted on this satellite until now. Can't wait until this evening to see if I can avoid the fade I have been experiencing. I am sure rain fade will be substantial with the smaller dish, how will winter effect the smaller dish?

 

[orac]

The LNB should be pointing to just below the center of the dish. You will get a signal from a strong TP.

mikelib, why not point it at the center of the dish?
_
Neil

 

[Bob2011]

UPDATE!

Ordered the DMX521 and bracket combo off of ebay for $12.95. Right now I am using the bracket with the JSC321S-2 Universal LNB I had and it works great. I get about 135 channels on 97w which is pretty good but you can see the weakness of this size dish on that satellite. It works perfect for 95w and CCTV is 95 Q. Over on 101 History, BIO, and BVN are strong with a few other foreign channels. Also had everything on Amazonas and right now its parked on the NBC mux at 72w. The other downside with this size dish is trying to use a cheap meter and finding satellites next to strong DBS satellites. Without the TV next to you outside you will be making many trips back and forth because of false readings.

Pixl, if you are still following this I did the freecycle thing and got a primestar yesterday The conditions were I had to take a small Directv dish as well and remove all poles. The primestar pole had a big concrete base but I finally got it out with a pull from a truck. Should be worth it if the LNB works after sitting there for more than 10 years. As for my 4 foot VSAT the LNB does work well but the dish is so heavy and with the mount style its really only good for one satellite. I may end up experimenting with a C band LNB on it now that I have 4 dishes