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Retrofitting your RV Winegard Dish for HDTV A step by step plan
By
Tom Knickerbocker
The current satellite dishes available for RV’rs cannot receive HDTV. The HD Programming uses 5 satellites (Direct TV) and has 5 LNB's mounted on a dish that is elliptical and about 2 times the size of the circular 18 inch that came with my crank up Winegard dish system. This is the one installed at the factory in 1993. It has one LNB and folds flat. I wanted to make sure the installation worked like the old one - folds and cranks up. I dropped Comcast cable service and subscribed to Direct TV HD. The technician arrived and setup the dish on my roof, installed the cabling and receiver (Dish H20-600) and then gave me a second dish set up. I think they get these from customers who move or cancel so they are surplus, but mine was brand new in the box. Just so we are clear - Trac Vision, King Dome and Winegard cannot receive HD as they presently are configured. Check before you buy a $1600 dome system. 1. I removed the existing 18" dish and LNB by removing the coax from the LNB head and the two C clip bolts at the point where the arm folds. Leave the rotating mount in place on the roof - you do not need to remove it. This is a good time to check for poor sealant and mounting screws. Repair as necessary. 2. I then placed the new dish on the support
bracket and found it was not going to lineup with the holes. Place the
dish in the center of the support leaving about 1/2"clearance at the
bottom. Drill holes and then file to create carriage bolt square patterns.
Install the bolts and mount the dish. See picture 1. 3. Carefully measure the distance
from the new LNB to the face of the center of the new dish (You can do
this when you assemble the dish or climb on your roof and check the one
the technician installed.) The distance should be 19.75 inches from the
back edge of the large LNB that is centered on the dish (This is the
triple LNB for HDTV). This is the focal distance you must replicate by
cutting and fabricating the new arm to fit on the old folding pivot point.
You will be removing the existing arm because it will be too short. But
don't discard this as you will have to use it for a pattern to drill
mounting holes, trim "ears" for the folding stop point and mount the
spring that unfolds the LNB when you raise the dish. It is best to slowly trim and fit so that you can find the exact length that results in the LNB focusing on the center of the dish, 24 degrees offset from the centerline and 19.75 +/- .1 inches from the face aiming point. You could use wood to make a template while the new dish is still assembled so you get it right the first time. Don't be intimidated by this description - it is not that hard if you take your time and measure at least twice. 4. When this is finished you will mount the dish and LNB on the coach, attach the coax and raise it so the face of the new dish is vertical. With the new arm pivoting in the front hole, (leave the spring out for the moment) mark the location of the ears where they will hit the second pin. If you file away a small amount at a time you will notice the arm pivots downward with each filing. The place to stop is when the distance is 19.75 inches (+/- .1) from the face. The ears are the fine tuning to be sure the focal point of the LNB is correct. Assuming you have assembled and filed this as described you should now remove the arm, install the spring through the top pin (make sure the notch is added or the spring will be broken when it folds down), and install the C clips. Add cable ties to hold the coax and any elevation
sensor cables (Winegard installed their MAGIC Sensor on most the crank
ups) and clean up the installation. When you go below and want to sight
your dish there is one more thing to be careful about. The satellite
aiming directions give three points to adjust, elevation, azimuth and
tilt. You will ignore the tilt because you simply can't tilt the dish when
you are mobile. This could affect some HD programming reception because
the axis of the dish may not be parallel to the line of the three
satellites Direct TV uses (110, 119, 91). In my area tilt is stated as 79
degrees which is 11 degrees right of vertical. This did not cause me a
problem with my reception. Azimuth (rotation) will be approximately as
stated in the guides or on your setup screen. Elevation will be about 7
degrees lower than stated - mine said sat 110 was 52.8 degrees but it
centered at 47 degrees. This is because of the elliptical shape of the
dish as compared with the circular old dish. Just use the satellite finder
and compass and fine tune inside until you get the maximum gain. For the
finished installation see picture 3. 3. This job took about five hours and required a few new bolts and labor, but now I have a crank up HDTV dish and it folds nicely for traveling. You may want to fabricate a “crutch” for the bottom of the feed arm so when it folds it will have support on the top of the roof. As you can see mine is diamond plate so punctures are not an issue. Yours may be rubber or some lighter covering. If so you would not want to have a crutch puncturing the roof and causing leaks. I travel at 65 mph and the top of the roof does not get much turbulence so the larger antenna dish has not appeared to be moving or vibrating and I have seen no ill effects of this addition. You can reach Tom at knitho at comcast.net ###
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In picture 2 you
can see the distance from the end of the arm (where the LNB fits into it)
to the top edge is 14-1/8". If you carefully trim the end of the arm to
16inches with a saw, you will have a blank that can then be filed to match
the ears, holes and cut out similar to the original Winegard. 