Installation questions (long)...

[good_ham]

I just ordered my HR10-250 today and am going tomorrow to a local retailer to get a 3 room package to cover the rest of the rooms. I do have several questions around installation I am hoping someone here can answer.

I've done an impromptu site survey and believe the only place I will be able to place the dish is well up on my (steeply pitched) roof. This is due to several dozen large trees in my back yard that pretty much cover the width of my yard.

I've decided to do the install myself for two reasons: Nothing about my install will be standard and I would rather do it myself than pay extra. That, and I am an anal perfectionist and I doubt I would be happy with the work of an installer based on what I've read here. I know there are good installers out there, but they seem to be the minority. I don't want to roll the dice particularly when you consider that they would be putting holes in my roof. I've installed several older round dish systems in the past and had no problems at all.

To determine where I can install the dish I made up a rig on top of a tripod with a base piece of wood that attaches to the tripod head connected to a piece of wood that is inclined 49 degrees (which is the elevation I got for my zip from d* website). To this I attached a 8 inch piece of 1/4" plastic tubing parallel to the edge of the inclined piece of wood. I got a compass that has a flat side and affixed it to the side of the base piece of wood. Now when I level the tripod I can aim the head using the compass, look through the tubing and see if there are any obstructions. I know they make professional equipment for doing this, but it would be overkill for my purposes. I put this together in a few minutes with stuff I had laying around excepting the compass.

The questions I have are as follows:

- How tight is the tolerance on obstructions? Is the dish "looking" at 49 degrees or somewhat higher as I've read? If there is an obstruction that stops right at 49 degrees am I risking not getting a signal? Likewise horizontally how close can an obstruction be? If I shoot through a gap in the trees that are not much more than the 18 degree span am I asking for trouble? I know the trees will grow, but the one closest to being in the way will be taken out this fall anyway. Should I be OK until then? Seems a satellite several thousand miles away would be a fairly small point.

- Is the azimuth the same for the oval dish as for the round one? As an aside, anyone have a clue why D* wouldn't update their website to provide tilt as well as ele/azi info given that most systems sold now include the triple LNB dish?

- Since I will be mounting on my roof, how would I attach to ground within 20' of the dish? It will be 40+ feet from the ground. Is tying into a ground from a circuit in my attic acceptable?

- For passing the cables in from the dish can I just drill a hole behind or below the mounting plate, run the cables through and fill in around it with patching tar? I guess what I am asking is, what is the proper way to route the cables?

- What are the length limits between dish and receiver? By the time I get from the roof to the basement, through a 5x8 switch, back to the attic and across the house the furthest run will be perhaps 140'. Seems I recall 100' was the limit? Does a switch extend that?

- Since the price of installation is included in the packages is there any benefit I could get from that? For instance, the install includes the cost of cable that I would have to buy otherwise. Could I schedule the install then just have the guy leave cable and split? Are they allowed to do that?

Sorry if any of these are dumb questions. I've looked around and found answers to the other 80 or 80 questions I had. I just can't find answers to these last few.

 

[dishjockey]

Your line of sight for an oval dish is going to be lower than for the single satellite round dish. Your best bet is to go to a local retailer that sell and installs not your local circuit city or chain store.
These guys will usually come do a site survey for free if you are going to buy from them.

 

[robert luzzi]

you do realize by self installing you are voiding any and all warrantys. as far as putting the dish on a roof that pitched, good luck getting a service call when the snow flies, cause it aint gonna happen........bob

 

[cr0mag]

- Since the price of installation is included in the packages is there any benefit I could get from that? For instance, the install includes the cost of cable that I would have to buy otherwise. Could I schedule the install then just have the guy leave cable and split? Are they allowed to do that?

They definately won't do that.... I tried a similar situation before and the installer wouldn't get paid for the visit if everything wasn't by the book. In retrospect, it seems fair to me.

 

[Rancid1]

- What are the length limits between dish and receiver? By the time I get from the roof to the basement, through a 5x8 switch, back to the attic and across the house the furthest run will be perhaps 140'. Seems I recall 100' was the limit? Does a switch extend that?

125' from dish to reciever. Can be extended with an in-line amp.

I'll leave the rest of the questions open for someone who's done more dish installs than me.

Good Luck

 

[Mike500]

Here are the two best techniques for roof installs and bringing cables into the attic;

DBS ROOF INSTALL TECHNIQUE

I install a lot of roof mounts on pitched asphalt shingle roofs. I never never use silicone or roofing cement or coatings. And, I never use those lag screws that require predrilling.

I use #14(1/4"dia) fully threaded hardened hex head drive sheet metal screws. I drive two three inch long ones into the rafters and four 1-1/2" long ones into the corners of the feet. It is not difficult to find the rafters, since hitting the roof surface with the back of your fist will result in a solid sound. Even if you miss, six fully threaded screws will provide a very good hold that will require a hurricane or a tornado to blow off. In that case, the home owner's insurance will apply, since it will be considered an "Act of God."

The above provides for one solid mount. The screws driven through the shingles, without predrilling, provides a near perfect seal, since the heat generated in driving them melts the asphalt, which rehardens around the screw. This is also basically how roofing nails work. Just for insurance and for those customers who inspect the install, I cover the heads with a pliable modeling clay like duct seal. A one pound brick costs no more that $2 at Home Depot. This is also perfect for sealing cable wall entries.
The best level that I have used is the Israeli made Post-Rite sold at Sears for $5.99. It is a post level with two bubbles spaced 90 degrees apart on a vertical hinge. The magnets don't work that well, but the elastic strap holds it firmly on the "J" pole. It's worth having, if you do a lot of installs. Forget the bubble level that fits on the inside of the mast. It requires you to get up and increase your center of gravity to look at it from the top, which can be dangerous on a steeply pitched roof. With the Post-Rite, you can do everything while sitting on the roof's surface and still have access to see the levels, without moving your position above and back down to the mounting.
The center of the dish mounting foot is usually marked with an embossed line down the center. Except for a very old mounting foot, one of the center holes is round, and the other is a slotted arc. The first step is to screw in the long 2-1/2" to 3" long screw into the round hole, just driven down enough so that you can pivot the foot on this one screw. Swing the pole up and down and pivot the foot until both bubbles on the Post-Rite are centered. Drive in the second lomg screw. Then, drive in the short corner screws until snug. Using the bolts and nuts that hold the pole to the foot, tighten them for a final adjustment, if plumb had shifted a little due to the roof shingles having been compressed from driving in the screws. Use small balls of duct seal the size of a small marble and work them over the screw heads.
Set the skew or tilt and elevation correctly on the dish correctly for the locality. Place the dish back on the pole and tighten the vertical clamp bolts just tight enough to take up all of the wobble. Swing the dish horizontally until you get the highest signal levelon the meter. Tighten the vertical sleeve mounting bolts. Check the TV to verify signals for each satellite position.

Removal of Dish Mount

Backing out the screws leaves holes of less that 1/4" that are almost undetectable to the casual observer on the ground. The mounting foot is not "glued" to the shingles and comes off without tearing them. Whoever thought gluing the mounting foot to the shingles provides security is a fool. If the wind blows the dish off in a hurricane, a lot of shingles comes off. If held only with screws, a dish blown off results in less damage. The duct seal is great for sealing the holes left from the removed screws. Filled holes can be very discrete.

If you are removing a previously "glued" mounting foot, the way to do this with the least damage is with a thin stainless steel wire, such as aircraft safety wire or a piece of piano wire wrapped between two sticks like a garotte. Saw away the silicone with the wire, and the mounting foot comes off pretty clean. I're even used this method to take off mirror tiles stuck to dry wall, without damaging the surface.

If you are replacing shingles, the dry wall knife is your best friend. It allows you to lift the heat activated glue down tabs of asphalt shingles without breaking them off.


How to install a roof cable entrance.

I'd go out and get a piece of 1-1/4" PVC conduit, a couple of same size 2 hole clamps, a service entrance head, and a vent flashing.

Go into the attic, using a 1-3/4" hole saw. Start it flat with the sheathing right next to a rafter. As it it cutting part way through, tilt the hole saw, until it is plumb. Outside; using a large putty knife or a dry wall taping knife, carefully lift the shingles around the hole. Remove any roofing nails at least a foot radius around the hole. Place the flashing over the hole, and cut a circular "U" out to match the flashing raised area plus 1 inch all around, starting at or below the center of the hole. Slide the flashing under the shingles, matching the raise area. Shove an 18 inch long piece of pvc conduit through the flashing and the hole in the sheathing. Inside the attic, strap the condiut to the rafter. Outside, nail down the bottom corners of the flashing and replace any nails taken out that held the shingles. Glue on the cable entrance weatherhead.

This is the correct and truly professional method of doing this.