DiSEqC motor setup

[statalite]

Hi All,

I'm about to venture into setup my first DiSEqC motor with an 80cm dish , I'm aware there's already some guides on the site and I will be reading as much as I can.

I purchased two second hand technomate motors, mainly because the first one didn't come with all the parts.
Both, however when I tell my portable meter "go to reference" the arm(s) does go to zero but it appears to be something like one millimeter off zero and I'm wondering if this is more 0.8w. Is this normal behavior? Could this be a coincidence?

Responses welcome.

 

[Mickha]

Arm(s)?

Setting up a DISEqC motor is probably the easiest, as you set everything to 0, motor, dish, and LNB.
Then enter your Latitude, and Longitude, into your receiver, remembering negative Longitude readings = West, Positive Longitude = East.

You then use your receiver to send your motor/dish to a suitable satellite, preferably one closest to your True South, your Longitude position, then physically adjust your dish. to get the strongest signal quality reading, you can get.

You need to use the USALS motor option, in your receiver, so that your receiver can automatically locate the satellites, based on your correct Latitude, and Longitude.

Then tighten everything up and check your readings on various satellites, by using your receiver to send the motor East, and West, noting your signal quality readings.

You can then send the motor back to your start up satellite, and adjust the motor bracket, the dish bracket, slightly, to once again get the strongest signal quality reading, and try East/West again.

You can use william-1's strongest transponder guide, to aid your search:

Just Sharing This - Strongest transponders

same here,rainy weather and midday time mean weak reception for 7w and it strengthens a lot after 7pm

satellites.co.uk

 

[Terryl]

I would align the dish and motor to true or magnetic South first, that way your on the arc of the Clark belt, that's where all the geosynchronous satellites are.

If you align to a satellite that is just close to South you may be off with all the others, once you align the dish and motor you can look for the closest satellite to South from your position.

dishpointer dot com has an app for this, enter your address and then select the due South option in the satellites section, it will also help you find the closest Southern satellite to you.

 

[Channel Hopper]

I wouldn't adjust the motor on a magnetic bearing, except as a starting point, the poles move around and have no bearing (sic) on where the satellites are.

 

[Channel Hopper]

By the way our star's own compass is about to flip, predicted in mid September with a variation of up to a month either side.

The sun’s poles are about to flip. It’s awesome — and slightly terrifying.

The sun is growing feistier. Great news for aurora watchers. Bad news for communication satellites.

www.vox.com

 

[rolfw]

I would align the dish and motor to true or magnetic South first, that way your on the arc of the Clark belt, that's where all the geosynchronous satellites are.

If you align to a satellite that is just close to South you may be off with all the others, once you align the dish and motor you can look for the closest satellite to South from your position.

dishpointer dot com has an app for this, enter your address and then select the due South option in the satellites section, it will also help you find the closest Southern satellite to you.

Personally find using a close to South reference is pretty much bulletproof with a USALS motor and very easy as long as the declination is set correctly on the motor body, I've never had a bad result when using the receiver to send the dish to my selected satellite. Admittedly my closest satellite is very close to due South, but have on a couple of times used one further off due South as a test and it still worked really well, with no further dish tweaking required.

 

[a33]

Both, however when I tell my portable meter "go to reference" the arm(s) does go to zero but it appears to be something like one millimeter off zero and I'm wondering if this is more 0.8w. Is this normal behavior?

"Normal" would be exactly at zero, when coming from the east, or coming from the west.
When you use only diseqc 1.2 GotoNn commands, there is no problem though; it doesn't affect pointing.

When you use diseqc 1.2 GotoX commands, so USALS commands or diseqc 1.3 commands (as they are sometimes called), there is a problem though; as GotoX is a command that says "goto x degrees left/right from the motor zero".

Resetting is done by rotating to exactly zero, and then give the reset command (though not all receivers have the reset option, I believe). Then all stored StoreNn positions are reset to default, and the zero position is set at the present position. And maybe also all limits are cleared; I'm not sure.

Does this help?

greetz,
A33

 

[Terryl]

Personally find using a close to South reference is pretty much bulletproof with a USALS motor and very easy as long as the declination is set correctly on the motor body, I've never had a bad result when using the receiver to send the dish to my selected satellite. Admittedly my closest satellite is very close to due South, but have on a couple of times used one further off due South as a test and it still worked really well, with no further dish tweaking required.

Well it may be true if your closest South satellite is very close to due South, but not all reading this thread would have a satellite close to South from their location, as in my case the closest Southerly satellite for me is 121W, (that I can use) but that puts an error of almost 2 degrees into the equation.

This is why it's important to first align everything to due South (or due North for those South of the Equator) first, then find your Southerly most satellite for zero.

 

[Terryl]

I wouldn't adjust the motor on a magnetic bearing, except as a starting point, the poles move around and have no bearing (sic) on where the satellites are.

You would need to know the current magnetic declination for your location to use magnetic South, (or North) if a compass is all you have then you would need to know that.

 

[statalite]

I have attached an image of each motor, are these considered as set to zero?
I don't think so personally but wanted to check I'm not going crazy.

 

[stel883_]

I think these are correct

 

[gdf68]

I have attached an image of each motor, are these considered as set to zero?
I don't think so personally but wanted to check I'm not going crazy.

Is that the position your meter sent them to,
I'm getting old eyes aren't the best but they look slightly off centre.
Can he manually move with the buttons get it to what looks zero(centered) and then
do as @a33 suggests and reset

 

[statalite]

I was able to make a more fine adjustment using the buttons under the motors and was able to reset them so onto the next part later in the week.

 

[a33]

Well it may be true if your closest South satellite is very close to due South, but not all reading this thread would have a satellite close to South from their location, as in my case the closest Southerly satellite for me is 121W, (that I can use) but that puts an error of almost 2 degrees into the equation.

This is why it's important to first align everything to due South (or due North for those South of the Equator) first, then find your Southerly most satellite for zero.

It is true that the motor axis angle (and the dish symmetry axis in line with it, and the LNB arm also in line with it) should azimuth-wise be set for the apex position (due south/north position, highest point of the arc).

However, for "finding" the correct 'azimuth' for the motor setup, you don't need a due south/north satellite at all; you can use any 'reference' satellite that you want. But of course, before trying to find that reference satellite (by rotating the whole setup op the pole, to find that satellite), the motor axis should be rotated to the proper setting for that reference satellite.

With USALS, that is done very very simply. I totally agree to @rolfw there.
Not with USALS, it is a bit less simple: you'd have to guess how much rotation is needed, or calculate the dish forward/backward movement at left and right side of the dish, or calculate the difference of actuator extension length for the reference satellite, for instance.
When you have found your reference satellite that way, also your apex (due south/north) aiming is correct.

So though it is comfortable to have a due south/north satellite, you don't really need one; if you properly account for the "error of almost 2 degrees into the equation"(see the quote above) beforehand.

There is a 'however', however: when your reference satellite is further away from due south/north, you'll have greater problems finding your reference satellite when your initial motor axis elevation angle and dish declination offset angle are further off from what they should be. So I would advise to set these angles with care.


Greetz,
A33

 

[statalite]

The next step, making the pole 90° I'm having difficulty with this, I have an digital inclinometer but can only reliably get the pole to 90° usually on the Y axis, but as everybody knows this is very sensitive calculation.
Pole support comprises of 4 of these braced on a concrete post like this, and am struggling with the X axis, not getting 90°, if I do, it then throws the Y axis out. I usually get anywhere between 89° and 90° for X and Y.
Am I wasting my time with the whole thing without getting 90° X axis and 90° Y axis?

 

[Mickha]

If you're siting your dish, at ground level, you could try an adjustable ground stand, like this:


As you can see it has bolts, which can be adjusted, to get the pole as near vertical as possible, and is secured to paving slabs, or concrete, and is sturdy.

 

[statalite]

If you're siting your dish, at ground level, you could try an adjustable ground stand, like this:
View attachment 155740

As you can see it has bolts, which can be adjusted, to get the pole as near vertical as possible, and is secured to paving slabs, or concrete, and is sturdy.

Unfortunately I don't have the facility for something like this.

 

[a33]

The next step, making the pole 90° I'm having difficulty with this, I have an digital inclinometer but can only reliably get the pole to 90° usually on the Y axis, but as everybody knows this is very sensitive calculation.
Pole support comprises of 4 of these braced on a concrete post like this, and am struggling with the X axis, not getting 90°, if I do, it then throws the Y axis out. I usually get anywhere between 89° and 90° for X and Y.
Am I wasting my time with the whole thing without getting 90° X axis and 90° Y axis?

I'm not sure what you call X and Y?

What I do know is that for a motor setup, the pole must be exactly plumb east/west-wise.
North/south-wise plumb is not quintessential, as that can be corrected/counteracted with the axis elevation setting.

Greetz,
A33

 

[Mickha]

If you have a secure concrete post, then all you have to do is put spacers, in the brackets, or longer bolts, with adjudtable nuts, one each side, of the bracket, so you can adjust them, to compensate for any minor pole alignment issue.

 

[statalite]

I'm not sure what you call X and Y?

What I do know is that for a motor setup, the pole must be exactly plumb east/west-wise.
North/south-wise plumb is not quintessential, as that can be corrected/counteracted with the axis elevation setting.

Greetz,
A33

Apologies for my terminology. X is East/West, Y is North/South looking down at the pole.