openbox with motor and cascaded diseqc

hairybadger

hairybadger

Bricoleur
My Satellite Setup
see sig
My Location
near Geneva, Haute-Savoie, France
Hi,
This post is just a quick description of my setup in the hope that it will help someone else.

satellite_setup.webp

Note the green lines represent multiple connections (typically 3 or 4). I'm no MS Paint master :)

I have an Openbox S10, firmware as up to date as I can get it, attached to a diseqc 1/10 with the following outgoing connections:
1 - motorized 60cm dish - single black ultra
2, 3, 4 - diseqc 1.0 1/4 switches and thence to the T-90. Note that I appear to have to put these switches on the 1/10 outputs numbered 8 or lower otherwise the receiver cannot select the correct LNB.
5+ - directly to the T-90

An LNB switched via the 1/10 and a 1/4 is configured, for example, as Diseqc 1.0 port 2, Diseqc 1.1 2 cascade port 6.

Getting the motor to play nice was a little tricky. I have configured the sats on the motor as diseqc1.1 - 1 Cascade M1, port1 although it'll also work as 2 cascade port 1 or even diseqc 1.1 disable since I have it connected to port 1. Motor type is USALS.

The tricky bit is this: if I select an LNB other than the motorized one I can no longer drive the motor (I still receive signal from the LNB from whichever satellite it happens to be pointing at) and have to restart the box to get it back. It took me a while to work this out. When restarting I need to make sure that I'm pointing to a motorized sat otherwise when the box comes back up again looking at a non-motorized sat I'll lose control of the motor again.

I've organized the satellites so I have the T-90 ones listed first, followed by all the motorized ones. This means that I can zap between sats on the motorized LNB without inadvertently selecting one going through the rest of the diseqc switching setup and thus losing control of the motor. Using this setup I have a lot of satellites doubled up. I'm interested to see that I can get 28.2E perfectly well with a 60cm dish, and that the 60cm pointing directly at 5W gets a better signal than a multiconnect hanging off the end of the T-90 (although this is to be expected).

Note that I haven't tried reversing the 1/10 1/4 arrangement (ie having the receiver connected to a single 1/4 and this then connected to 4 (!!) 1/10 switches). My mounting pole isn't particularly vertical (OK - is quite a way out) but this doesn't seem to be causing me any problems, probably because the dish I'm using is 60cm and thus its directionality is relatively weak. I'll fix the verticality when I find a more permanent location for the dish.
 
You have to go through the motor first and then to the DISEqC switch. If you try to put that much load through the switch it will just burn it out.

As far as i know (I have never tried this in case your wondering, I've just seen someone say this is how to do it ) You go into the motor first and then to the output port of the DISEqC switch. Port 1 goes to lnb on motorised dish. The other ports go into the cascade for the lnbs on the T-90. A DISEqC switch isn't designed to take the load that will be put through it when trying to move the motor.

It usually works a few times then it just burns out the switch.

Nano
 
nano said:
You have to go through the motor first and then to the DISEqC switch. If you try to put that much load through the switch it will just burn it out.

As far as i know (I have never tried this in case your wondering, I've just seen someone say this is how to do it ) You go into the motor first and then to the output port of the DISEqC switch. Port 1 goes to lnb on motorised dish. The other ports go into the cascade for the lnbs on the T-90. A DISEqC switch isn't designed to take the load that will be put through it when trying to move the motor.

It usually works a few times then it just burns out the switch.
Click to expand...
Great - thanks for that. It's been functioning like that for a few weeks but I take your point. I'll reorganize things when I have a bit of time and report back :) The extra insertion loss will be acceptable for the satellites I watch on the T-90.
 
500mA pass-through is the usual rating on DiSEqC switches: I have a Motorised 1.1m connected downstream of a DiSEqC switch and also a Motorised 80cm ditto.

Works fine.

Max motor current should be 350mA or so at 18V, leaving sufficient margin for supplying the relevant LNB without exceeding the switch rating.

But whether this is pushing to hard at the margin is a matter only time will reveal!

It's also worth checking the max. current sourcing capability for your Receiver(s)............... if it is a tad wimpish, maybe that's why you need to restart? If so, always target a Vertically polarised Channel as the motor demand at 13v is less (albeit the motor moves more slowly).
 
BTW, both systems as mentioned in my last Post are associated with Skybox F3 Receivers and these are essentially Openbox derivatives so I presume the LNB/DiSEqC current sourcing capacity is similar.

I've just done a little experiment as your comment about motor reluctance struck a vague chord and I've established that if switching from a non-motorised position to a motorised one, the motor will only move if the target is H (18v). Subsequently, it happily moves from motorised position to motorised position without constraint.

Ok, that's not quite what you described, but your DiSEqC switching is somewhat different to mine - However, the root cause could well be the same.

Not sure why this should be, but try it yourself. Perhaps the 18V gives that extra bit of kick to unstick the DiSEqC switch relay? No idea, really, but it's a minor issue anyhow. Much quicker to select an H target than to reboot the Box, though!
 
Tivù said:
500mA pass-through is the usual rating on DiSEqC switches: I have a Motorised 1.1m connected downstream of a DiSEqC switch and also a Motorised 80cm ditto.

Works fine.

Max motor current should be 350mA or so at 18V, leaving sufficient margin for supplying the relevant LNB without exceeding the switch rating.
Click to expand...
OK - the motor says 350mA, the switch to which it's connected is rated at 500mA. I haven't grilled it so far but it's no Spaun, so who knows.....

Tivù said:
BTW, both systems as mentioned in my last Post are associated with Skybox F3 Receivers and these are essentially Openbox derivatives so I presume the LNB/DiSEqC current sourcing capacity is similar.

I've just done a little experiment as your comment about motor reluctance struck a vague chord and I've established that if switching from a non-motorised position to a motorised one, the motor will only move if the target is H (18v). Subsequently, it happily moves from motorised position to motorised position without constraint.
self. Perhaps the 18V gives that extra bit of kick to unstick the DiSEqC switch relay? No idea, really, but it's a minor issue anyhow. Much quicker to select an H target than to reboot the Box, though!
Click to expand...
Gave this a whirl, no dice. Thanks for the idea though :) Maybe if I shorten the cable - currently the motor is attached via a cable that's maybe 10m longer than it needs to be.
 
Ok, it was just a thought.

I tend to put up with minor foibles these days - not so long ago I wanted everything to work flawlessly and would go to great lenghts to make it so.

But the return on effort is no longer sustainable in my dotage!
 
Tivù said:
I tend to put up with minor foibles these days - not so long ago I wanted everything to work flawlessly and would go to great lenghts to make it so.

But the return on effort is no longer sustainable in my dotage!
Click to expand...
Heh :) Well the return on effort on getting X channels in Y different languages that I don't understand is pretty small anyway... Even more difficult is explaining it to my wife. "Because it's there" may work for mountains; it's less understandable for TV channels :)
 
Not sure I'm reading correctly what is required ..but Why assume the signal has to pass through the motor on its way from the lnb..
I've used a T splitter F connector to great effect in the past to avoid exactly this ..
Thus any lnb can be selected and if usuals activated with each lnb ..it will moe to the preset position..
Not many wouyld need this of course ..as the lnb at the focus could be moved to see any sat ..BUT ..where I do find this system useful ..is if you hang a different type lnb on the offset bar ..
In my case I cad a C band lnb to the left ..Ku at the focus ..and Ka to the right ..
rgds
VS
 

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nano said:
You have to go through the motor first and then to the DISEqC switch. If you try to put that much load through the switch it will just burn it out.
Click to expand...
If you go through the motor first you can't have multiple motors... and you need to run the cabling all the way to the motorised dish and then back to the switch (which might be many meters away). The motor of my Fibo 90 is downstream of the switch and that has worked fine for more than 2 years in that configuration. The only time you will burn out the switch is if the dish is too heavy for the motor, and even then it would still need a receiver that could supply a high enough current to burn out the switch. Most receivers have a current limiting circuit to protect themselves against a short on the cable so in theory should never supply a current that is high enough to burn out a switch... but then again if you were to use a really cheap switch...
 
I had a problem with an F3, where the motor failed to turn most of the time. It turned out to be an inline meter that was drrawing too much current from the receiver. Removed the meter and it still works fine today. It was only a cheap £5 meter so just the very slight current drain of the meter was causing the voltage to drop or interfering with the disecq commands.
 
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