diseqc switch and 2 antennas

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ZetaMale

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I guess I misunderstand how diseqc switches work. On my system I have a diseqc 2x1 switch with LNB1 attached to my C band dish via a Vbox and the LNB2 port is attached to my 90 cm Ku dish. Of course, the Azbox is connected to the RX port of the switch. The Azbox is set up to access the C band dish via the LNB1 port and the Ku via the LNB2 port. The C band setup uses Diseqc 1.2 for motor control and the Ku band side uses USALS. When I select a C band sat, shouldn't the motor commands be sent to the LNB1 port of the switch and the LNB2 port sends commands to the Ku dish? Or are both dishes suppose to move to the same sat together? Maybe the switch is bad? I bought this switch when I bought my Pansat 300 so maybe the switch is an incompatible version?
 
My understanding is motor commands are sent first, before the switch commands. Likewise, the conventional wisdom is the motor must be the first thing in line from the receiver. So I'll guess the specific problem you are seeing is the wrong dish is moving when you try to switch between the two? This would mean your switch is operating exactly as expected.

That's the quick answer. I'm certain there are others about to chime in with additional thoughts and maybe a good solution.
 
My understanding is motor commands are sent first, before the switch commands. Likewise, the conventional wisdom is the motor must be the first thing in line from the receiver. So I'll guess the specific problem you are seeing is the wrong dish is moving when you try to switch between the two? This would mean your switch is operating exactly as expected.

That's the quick answer. I'm certain there are others about to chime in with additional thoughts and maybe a good solution.

I was just reading Anoles FAQ on switches. Apparently I need to connect the receiver directly to the motor and then to the switch and then to the LNBF. I need more coax. But, how do you run 2 antennas from one FTA receiver? Is that even possible? I didn't see anything on that in Anoles FAQ. I suppose I could put a C/Ku LNBF on the new antenna.
 
Yeah, he has done a good job there trying to cover almost any configuration. I guess the one limitation is in fact multiple motors. I have two motors myself, one attached to a V-Box, but my solution was multiple receivers.

I'll make a suggestion since you asked, but I must warn you it isn't necessarily a good one since I've no experience in this area. Particularly because you'll need to buy more coax, it might be better to wait for those other experts to chime in. However, I might try an experiment with the V-box and the other motor - put both of them "first". See if one passes 1.2 commands, that way both motors move. Not ideal but it could work for you. On second thought, there has got to be a thread around here about that. This surely isn't the first time anyone tried to do this...
 
Would the attached arrangement work? The first image is how things are connected now and the second image is a possibility. The proposed arrangement would move both antennas regardless of band, though.

Well, I guess it can't be done. Time for plan M.
 

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dually motors

From what others have said, one cannot put two motors inline with the same box. The problem here is the fact that both contollers use exactly the same command sets for each motor controller. If you program one set for one dish, then another complete list for the other motor, both motors will move, but the one selected will move to its correct position. A mechanical A/B switch that toggles the signals/voltages direction to the single motor without a command set function will solve the problem, but you have to manually (rather than by remote) push/slide the button on the switch to direct the commands and power for the motor you want, which can be done inside the home. I believe the remote A/B switch by RAt shack and others could make it "by remote control"...

These types of switches (mechanical A/B) are usable with 18/14 vdc, but one must be carefull to unplug everything before your initial connection, and buy a quality high iso type (plastic) that you have maybe tested with signal only, finding it to be "DC" compatible.

On the design side of a receiver compatibility switch like this one, it would be easy to remove one command from the DISEq 1.2 set, and put it into an outside switch, though nobody has done it...

In Addendum: The problem here in switches and compatibility is that each DISEq switch made must conform to the commands sent by the receiver, 1.2 being a number of tones, or frequencies, that it must accept to be used, or controlled, by a receiver that supplies these commands. Also, in 1.2 switch, the DC is directed to a single port, which means that it only has to supply dc to one lnbf, allowing large numbers of lnbf's to be hooked to it without overloading a receivers lnb voltage regulator. On a motor controller, either by vbox or receiver to sg2100, etc.; making the motor move uses about all the juice it can supply. Trying to move 2 motors is a little taxing of such Power supplies, and this is where ""lock ups" occur. Making an extra port for dual motors can be done by building into a 1.2 switch, say the last available command, to be used by a receiver or vbox, as this extra "placement" to make the switch act for only that port to be "motor 2, 5th port" and it will still only supply that port with DC.

:angel::tux:
 
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@richyrich

Not true, both motorised dishes working fine here on AZ+ and also tested first on a CS 5000, so, it does work. The complication here is the VBox...........I would like to know how it can be done too for future inclusion of a 8 footer.
 
On a motor controller, either by vbox or receiver to sg2100, etc.; making the motor move uses about all the juice it can supply.

The Vbox only accepts commands, it doesn't use power from the FTA receiver to power a motor/actuator.
 
problem with new arrangement

I gave up on the idea of controlling 2 antennas with one FTA receiver.

However, I want to ask why the arrangement shown in the first attachment works 100%. In the second attachment/arrangement, I can't get anything through the LNB1 (C-band) port of the Diseqc switch - the Ku signals get through on the LNB2 port, though. The BUD LNB has power since I get 4DTV DCII on T7 (the BUD LNB power comes from the 4DTV). My guess is that the LNB1 port of the switch never gets selected. My understanding is that the second arrangement is the correct way for a motor to be attached and that this arrangement should work. Anyone know why?
 

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I gave up on the idea of controlling 2 antennas with one FTA receiver.

However, I want to ask why the arrangement shown in the first attachment works 100%. In the second attachment/arrangement, I can't get anything through the LNB1 (C-band) port of the Diseqc switch - the Ku signals get through on the LNB2 port, though. The BUD LNB has power since I get 4DTV DCII on T7 (the BUD LNB power comes from the 4DTV). My guess is that the LNB1 port of the switch never gets selected. My understanding is that the second arrangement is the correct way for a motor to be attached and that this arrangement should work. Anyone know why?

The answer is: Port 1 on a DISEq switch is selected by "no tone", and when a moto drives to a position, "a tone" comes from the receiver, which selects "upper ports", not port 1.
 
The answer is: Port 1 on a DISEq switch is selected by "no tone", and when a moto drives to a position, "a tone" comes from the receiver, which selects "upper ports", not port 1.

I'm not sure if we're talking about the same thing. Port 1 on my switch is labeled RX (connects to the FTA receiver). If you look at my drawing labeled sat0004.jpeg, on the previous page, I was trying to arrange the setup where the FTA receiver connects to the SG9120 motor which in turn connects to the switch port that is labeled RX. Then the BUD C-band LNB conects to the port labeled LNB1 and the 90cm Ku band LNBF connects to LNB2. The FTA receiver is setup to select the LNB1 port for C-band transponders while the receiver selects the LNB2 port for Ku band. The SG9120 motor moves the 90cm dish while the 4DTV moves the BUD. Even though the SG9120 motor moves the 90cm dish, I assumed that the receiver could still select either LNB1 or LNB2 depending on how the ports are selected by the FTA receiver (in other words, I expect the SG9120 to pass thru the diseqc commands at all times). But, only the LNB2 port is selected while the LNB1 port never is. I know the switch is good because the arrangement shown in drawing sat0003.jpeg works. I hope that I clearly explained the situation this time.

Another interesting thing is that Anole's FAQ indicated that my arrangement in drawing sat0003.jpeg would burn up the diseqc switch but it hasn't happened to me.
 
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