Maximum amount of coax for a diseqc motor?

[Thun]

Hi,

I have a mini BUD with a diseqc motor. Due to some line of sight issues, I'm going to need around 300 feet of coax to hook everything up. I'm using a Kbox as a dish mover and no switches and planning to use RG 6.

Do diseqc motors have a maximum distance limit on coax before they stop working?

Thanks,

[Terryl]

300 feet is way too long for RG-6 coax, the signal loss would be too great.

RG-11 would be the best bet for that long of a run, but it's costly.

Why do you need 300 feet?

[Thun]

Why do you need 300 feet?

Trying to get Anik F3 118 W in the middle of a forest. Here it comes in at 26 degrees off the horizon. The only spot that can get that bird is about 275 feet away from the television. Tested the spot with a bunch of joined cables and a 36" dish with a Ku LNB and was able to get a signal and scan stuff in. This is just for the cottage in the summer. Prefer not to get out the chainsaw and pole pruner if possible!

[Terryl]

Then I would recommend that you use RG-11, inside 3/4" EMT conduit, that way you have even more shielding.

A 10 gauge solid copper ground wire should also be used, as the steel conduit is not that good of a conductor, if your going to bury the conduit, I would recommend that you use the compression conduit fittings, and use some pipe dope on the fittings, this will keep the conduit dry.

If you use 1" conduit you can run AC power down to the dish, or a separate run of 1/2" PVC conduit can be used for the AC power.

You want one single run of coax, as every connection adds to the system loss.

If you need more then one coax you will have to go to a 1" size conduit as the RG-11 is about .4" in diameter, it also takes special connectors.

[Terryl]

You can also go with some hardline, but that is not cheap.

[Gold]

Then I would recommend that you use RG-11, inside 3/4" EMT conduit, that way you have even more shielding.

A 10 gauge solid copper ground wire should also be used, as the steel conduit is not that good of a conductor, if your going to bury the conduit, I would recommend that you use the compression conduit fittings, and use some pipe dope on the fittings, this will keep the conduit dry.

If you use 1" conduit you can run AC power down to the dish, or a separate run of 1/2" PVC conduit can be used for the AC power.

You want one single run of coax, as every connection adds to the system loss.

If you need more then one coax you will have to go to a 1" size conduit as the RG-11 is about .4" in diameter, it also takes special connectors.

I bought Flooded RG-11 when I installed my BUD's.
I still ran it in conduit, but I used 2" for two BUD's. When you consider the size of the RG-11 & the four other wires per/dish for the actuator. It pretty much filled up the conduit.

The price has really come down on the wire. I paid the same price for RG-11 as solid copper RG-6.
The snap-n-seal ends were another matter. They were expensive & require new compression tools, & a new cutter.

I also had a backhoe dig my ditch deep enough. I drive an 18,000 loader over it & don't want trouble


Hi,

I have a mini BUD with a diseqc motor. Due to some line of sight issues, I'm going to need around 300 feet of coax to hook everything up. I'm using a Kbox as a dish mover and no switches and planning to use RG 6.

Do diseqc motors have a maximum distance limit on coax before they stop working?

Thanks,

I would think you could get by with solid copper RG-6, but I know RG-11 will work...
RG-11 has some down sides.
Compression are expensive
Compression tools are expensive
It does not bend well, so it's hard to fish in a wall.

[Thun]

Not much luck finding RG 11 around here.

I have 4 various dishes and each is using at least 100 feet of RG 6 and I don't have problems with any of them with that much length. Even if I lose 10-20% signal that's nothing as I have trees everywhere and I'm use to signal drops when it gets windy as most of them are aimed at gaps in between trees.

How much signal loss do you have per added feet--ie, 10% signal loss per 50 extra feet and would an inline amp be useful?

[satchick]

With the diseqc motor, the bigger problem is voltage drop. At 300 feet you're going to have problems with the motor moving very slowly (or not at all), among other things.

[Thun]

At 300 feet you're going to have problems with the motor moving very slowly (or not at all), among other things.

I anticipate the other things would include the joys of dragging cable through 300 feet of poison ivy and deerflies, yes?

[Terryl]

Yes that brings up another good point Satchick.

When working with DC voltages the longer the coax, the more DC voltage drop there will be, solid copper core coax will help compensate for that, or if you only want the one satellite (118.8W) then you won't need to use a motor, then you only have to worry about the over all signal loss.

Your working with an RF signal at anywhere from 900 MHz to 2.4 GHz, or higher if your using a band stacked LNB from dish.

So lets use some standard RG-6 coax with a solid copper center.

At 1000 MHz (1 GHz) it's signal loss is 7.3 dB per 100 feet, at 3 GHz it is 13.7 dB per 100 feet, so at 300 feet it will be 21.9 dB at 1 GHz, and 41.1 dB at 3 GHz.



Now lets us some RG-11, with a solid copper center.

At 1000 MHz (1 GHz) it's signal loss is 4.3 dB per 100 feet, at 3 GHz it is 8.2 dB per 100 feet, so at 300 feet it will be 12.9 dB at 1 GHz, and 24.6 dB at 3 GHz.


So you can see the big difference in using RG-11 vs RG-6.

Oh, voltage drop on RG- 6 at 300 feet will be around 1.1 volt, this is based on 6.4 ohms per 1000 feet on the center conductor, and 2.8 ohms per 1000 feet on the shield for RG-6, using a 400 mA current draw on the motor, with LNB.

and the voltage drop on RG- 11 at 300 feet will be around a half a volt, this is based on 2.5 ohms per 1000 feet on the center conductor, and 1.6 ohms per 1000 feet on the shield for RG-6.


So if you use RG-6 you could run into a motor stall problem, as when your looking at the Vertical transponders, the DC voltage is only 13 volts, add in the voltage drop on the RG-6 and your at 11.9 volts there or about.

[slugworth]

ditch the motor and use a fixed dish.

[jvvh5897]

How about ditch the L band? Have a water-tight enclosure at the dish to house the reciever and just run channel output from the box and AC to the box. Might be able to run remote control through the coax to the box if you get tricky--it is just a 33KHz carrier that is pulsed.

[satchick]

I'm not sure if that's the right approach either... In the end you're still dealing with a 300' coax run and the fairly weak signal from the receiver's RF output. I would just source some RG11 and connectors online and do a regular installation that way.

[Thun]

Just for fun today I added another 175 feet to the 100 feet of coax on my mini BUD that was pointed to 99 W and the signal strength fluctuated between 71% and 67% where it normally stays at 71% according to the Openbox. Didn't try the motor. That was with four pieces of cable pieced together. I take it those Caribbean feeds on TP 3845 are fairly strong. How strong is the TP 3920 on 118 W?

[seahappy]

I am using a 33 inch with a motor that is about 300 feet (because of heavy woods) .. I am using R-11 and it has worked well for many years ....... ( I purchased a reel of R-11 with connections and tool that I found on Craig's List that a former Installer had, cheap... I also got one reel with a steel messenger wire for overhead use) ....Lol