Motorised and fixed to DC splitter and switch

foseco

Member
My Satellite Setup
80cm and 1m motorised dishes, 30w to 53e. DM500 and DM800. Server running MS Server 2008. Freenas NAS. Custom built desktop PC and 2 x laptops all running Windows 7.
My Location
Staffordshire, UK
Hi. I am trying to setup a motorised and fixed dish to two receivers, a DM800 and DM500. I have the fixed dish running with a quad lnb to a Chess 2x1 diseqc switch, one for each receiver and that works fine. The problem comes when I vector in the motorised dish. I can connect it to either switch and it works fine but I would like to connect it to both at the same time. I know the problems with controlling a motor from two receivers. I don't intend to have them both controlling it at the same time, I just need them both to be able to use it if they need to. I thought of using a DC splitter with DC pass through on both ports. I have used this on another system in the past and it worked without a problem. On this system however I connected the motorised dish to the DC splitter and then to the Chess switch, I still get the fixed dish but nothing on the motorised feed. Should this setup work? Is it likely that the switch is interfering with the splitter?

Thanks
 
Cant be done.
The DC voltage from one receiver would feed back on the other, (not unless you get into some very very expensive DC switches) all LNB polarities would have to be the same on both receivers at all times, if one receiver was looking at an H polarity transponder and the other was looking at a V polarity transponder the receiver on the V polarity would drag down the DC voltage on the whole system.

(H= 18 volts DC, V= 14 volts DC)

Also the motor would have to be put back to the zero point or reference satellite before the other receiver took over or it would get hopelessly confused as to where it is on the arc.
If #1 receiver was to be on satellite “A” at 25 East and then #2 receiver wants to look at satellite “B” at 2 East, receiver #1 won’t know what to think if you want it to go to satellite “C” at 7East.

There would also be a massive confliction on the motors DiSEqC commands coming from two receivers at once, the motor wont know what to do.
 
Ok, as I said in my first post, I don't want to use them both at the same time. Neither of the receivers will be on at the same time. I just need them both to be able to control the motor if they need to. I have already done this on the system at my parents with both receivers connected to the motor via a DC splitter and both can control the motor so I know that it can be done. With USALS the motor knows what angle it is at and if I power off the one receiver and use the other receiver the dish moves to the correct position. The only problem comes if you want to watch a channel on the same satellite the other receiver was using, then you have to tune off the satellite and back on before it picks it up.

I am now setting this up on a new system and all I need to know is if there is likely to be a conflict with a switch and a DC splitter as I cannot get the motorised feed when it is connected that way. I only have the one receiver in at the moment, I need to get the one working before I put the other one into the mix.
 
Now you are seeing the possible problems using this type of setup.

If you got it to work in the past then you will have to duplicate the exact setup that is working now, any deviation from that setup will/would cause problems.
 
Perhaps you could draw a diagram of how you have things connected, as what you have written is unclear.

I have seen a splitter working between two receivers to drive a motorised dish, and as you say, it works, but one receiver must be off.

I have also had a diseqc switch working in conjunction with a motor, and it works OK, and as you say you have to go to a different satellite and back again if the dish was moved by the other receiver.

But never a combination of the above, a digram would help to understand the logic of how you are trying to do it.
 
Ok, I have attached a diagram of what I am trying to do. At the moment I have it setup as per the diagram except for the splitter part. If I put that in, I lose the motorised feed. Sorry for the poorness of my artwork.

Just out of interest, I found a link to a website which seems to have a similar setup but uses DC pass on only one port. Here is the link...
http://www.sadoun.com/Sat/Products/Accessories/Dishes/Bud-slave.htm
 

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In theory, that could work, however, it is essential that the receiver that is not being used to control the motor is switched to the fixed dish first.


It is a good idea to build the system up gradually I think.

The first thing would be to get the diseqc switch, the motor and one reveiver, working together.

Then add the splitter.

Then make sure the splitter works using either leg.

Then add the bottom half of your diagram.

Incidentally, you initially said that you would only want one receiver working at a time, but you have put two diseqc switches in. Only one diseqc switch would be needed if the spltter was put first in the chain, followed by the switch followed by the motor.
 
I don't have any direct experience with this but would I be right in saying that the setup would have to be USALS rather than DiSeqC?
 
No, it could be either, as long as the positions stored for each satellite in each receiver were the same. Actually, when I saw it working, Diseqc 1.2 was being used.
 
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