ITB DM45 motor tube bend

[walrus1957]

This might be the wrong section to post this question so please bear with me. I am trying to help a friend that purchased a "ITB DM45" motor 3 years ago and does not have the users guide for it. It appears to be the same as my SG2100 motor, but his is tagged "ITB DM45". I know some web stores advertize as SG2100/DM45 for the motor.

He is having difficulties aligning his dish to the arc, his dish elevation settings make no scince to me. I would have quessed that the tube bend would have been the same as my SG2100 "30 degrees", and his declination angle is 6.8 so his dish elevation angle should be set to 23.2 degrees. However it is closer to 32 degrees, and only tracking a portion of the arc. I feel his motor latitude setting maybe in error a degree or two, but would like to confirm the motor tube bend. I can not find any information for the specified tube bend of the DM45 motor. Does anyone have one of these motors tagged as "ITB DM45" that you have aligned to the arc and can tell me for sure what the tube bend is for this motor? I would guess it to be either 30, 35 or 40 degrees?

Any input much appreciated,
walrus1957

 

[Anole]

first step:

Does the bracket which holds the motor and bolts it to the pole, have alignment numbers stamped on both sides?
Those motors will often have one set of scales marked in Latitude on one side.
Then, the other side will have a scale marked in Elevation.

I don't have a working 2100, but as I recall, you want to set the Latitude side of the bracket to your actual latitude.
Then of course, readjust the dish's elevation bracket on your true south bird to reacquire it.

The Sadoun web site used to have a set of tables for various motors with the angles you seek.
I'm not seeing it right now, but will update this post if I locate it.


edit: here's a fairly comprehensive set of install instructions for many motors.
Unfortunately, I cannot find the table he used to have.

 

[walrus1957]

His motor has both the elevation and latitude scale markings. He has it set on the latitude scale to his dish loacation of 45.5 degrees north latitude. His declination angle is 6.8 degrees, if the tube bend was 30 degrees his dish elevation would be 23.2 degrres, if the tube angle was 35 then the dish elevation angle would be 28.2 degrees, and if the tube bend was 40 then the dish elevation angle would be 33.2 degrees.

However when he selects his south sat of 74W (73.8 west longitude is his dish site), then a 30 degree elevation setting of the dish is optimum. When he selects satellite 110W then 34 degrees is his optimum dish elevation setting. I think his motor tilt still maybe in error or his pole isn't truly plumb even though he has checked it several times.

I have called and emailed Companys selling the DM45 motor asking for a copy of the users manual or at the very least give me the spicification for tube bend of the motor, but never received a reply. I have checked many forums and googled the motor model number but haven't come across anyone stating the angle of the motor tube bend. To complicate the situation more for troubleshooting, not only are we unsure of the tube bend but he can not test the east side of the arc as trees block all satellites east of 74W (top of the arc) position for him.

 

[walrus1957]

Thought I should add this; I have installed numerous motorized dish setups. I never had a problem installing either on a pole for a yard install or on a roof. However my friend lives 500 or so miles from me and I am troubleshooting his alignment problem through emails. So there is no way for me to confirm any of his settings other than photos he sends me.

I have sent him numerous illustrations of alignment problems that can be found in motor user manuals, and from other sources. But to be totally conclusive one must be able to test top of the arc and satellites east and west on the arc.

 

[Anole]

1. dish elevation markings are always suspect.
If anything doesn't add up, I ignore dish markings.

2. his LNB mounting arm may be bent, throwing off elevation

3. his LNB or LNB holder may be suspect, again, throwing off elevation.

4. and the thing you suspect, his mounting pole may be sagging under the load of the motor and dish.
It really should be verified WITH all the hardware hanging off it.

5. he's had this stuff three years...? and . . .
- it's worked withOUT the motor just fine?
- so he knows how to setup and operate his receiver?
- the motor's been stored out in the weather all these years?

6. since you're experienced, it's hard to imagine what you might have overlooked.
(if anything)
But, I wouldn't care about the tube bend angle.
Once the Latitude scale was set, the mount pole was plumb under the motor & dish weight, I'd run the dish's elevation up 'n down 'till I acquired the true south (or some close) bird.

7. oh, there is one possibility that might bite you in the rear...
Some users have reported troubles with 2100 motors.
I haven't followed all the details, but they did seem to be manufacturing defects, or firmware defects, and not user errors.
I can't point you to a specific thread, but you can search, or maybe one of the members who was involved with that problem will comment if your trouble seems familiar.
Of course, that was more prevalent in more recent motors, not old ones...

Best I can offer. -

 

[walrus1957]

1. dish elevation markings are always suspect.
If anything doesn't add up, I ignore dish markings.

2. his LNB mounting arm may be bent, throwing off elevation

3. his LNB or LNB holder may be suspect, again, throwing off elevation.

4. and the thing you suspect, his mounting pole may be sagging under the load of the motor and dish.
It really should be verified WITH all the hardware hanging off it.

5. he's had this stuff three years...? and . . .
- it's worked withOUT the motor just fine?
- so he knows how to setup and operate his receiver?
- the motor's been stored out in the weather all these years?

6. since you're experienced, it's hard to imagine what you might have overlooked.
(if anything)
But, I wouldn't care about the tube bend angle.
Once the Latitude scale was set, the mount pole was plumb under the motor & dish weight, I'd run the dish's elevation up 'n down 'till I acquired the true south (or some close) bird.

7. oh, there is one possibility that might bite you in the rear...
Some users have reported troubles with 2100 motors.
I haven't followed all the details, but they did seem to be manufacturing defects, or firmware defects, and not user errors.
I can't point you to a specific thread, but you can search, or maybe one of the members who was involved with that problem will comment if your trouble seems familiar.
Of course, that was more prevalent in more recent motors, not old ones...

Best I can offer. -

Anole-

Sounds like you setup a few motorized dishes yourself. Strange that you mentioned problems with the LNB support arm. The very first dish I purchased to motorize was the DS2076 Winegard, manufcatured prior to a certain date and the LNB support arm was not fully bent to form the proper alignment of the LNB. Boy that took a little time to figure out. After that incident I check all my LNB placements and add supporting struts from the lnb arm back to the dish so it holds in place regardless the weight of the LNB or any side wind loading.

Biggest thing right now for my friend is that his roof is covered with two feet of snow and any further adjustments or testing will have to wait until spring. I have photos of his roof setup, and he needs to redo everything, he agrees with me and come spring he will be replacing his mast and adding support struts, along with added supports to the lnb arm. The mounting post being sturdy and plumb, and the LNB arm being positioned correctly as well as the LNB is the crucial building blocks of the motoized foudation. Nothing beyound this point of alignment procedure can ever be acomplished without a plumb pole.

So yes there are a lot of things that can be a mess with my friends setup. He purchased the motor and a 90cm dish three years ago but only recently began in earnest the past 6 months to align it to the arc. If he aligns the dish for the top of the arc (74W) his dish elevation is set to 30 degrees, his motor tilt is set to 45.5 on the latitude scale (not the elevation scale side). His dish site is roughly 73.8W longitude and 45.5N latitude. He states his pole is plumb, but starts loosing the arc any further west than satellite 97W. By the time he is at 119W he is roughly 4 degrees low on the arc. This tells me he has two possible problems or a combination of the two; First being his pole is leaning to the west a few degrees, second being his motor tilt is off a few degrees and so would be the elevation setting of his dish, or a combination of the two.

Sure would like to find out what the tube angle of the motor truly is. If no one knows I am sugesting to him to try 23.2, then 28.2, then 33.2 as dish elevation settings. At each of these settings select top of the arc 74W, then adjust the motor tilt until he max out signal quality on 74W, then check satellite 119 or 123 or 129 and see how close to the arc it is following. Which ever dish elevation setting gets him the closets would have to be the motor tube bend (30, 35 or 40 degrees). I know scale markings even on the dish can be somewhat in error but should be close.

If you know the motor tube bend, and you set the correct dish elevation by subtracting declination angle from tube bend. Then set the motor to the dish site latitude on latitude scale of the motor. Then mount then motor to plumb pole and dial in azimuth. You should be so close all that needs be done is fine tunng. You shouldn't be spot on at top of the arc and then be 4 degrees low 40 degrees west of the top of the arc unless something is really off somewhere!

So again to everyone; Does anyone have a motor tagged "ITB DM45" and can you confirm the tube bend angle?

 

[Wescopc]

If your friend could measure the angle of the "face" of the motor with an inclinometer and subtract that from 90° he would have the angle of the shaft. That angle should match his latitude. If you get the shaft set to the latitude, then find the satellite, the angle of the shaft adapter (motor tube) won't matter.
Bob

 

[walrus1957]

If your friend could measure the angle of the "face" of the motor with an inclinometer and subtract that from 90° he would have the angle of the shaft. That angle should match his latitude. If you get the shaft set to the latitude, then find the satellite, the angle of the shaft adapter (motor tube) won't matter.
Bob

A few months back before I got involved, my younger brother was helping him figure out his problem. At that time he borrowed and inclinometer from a friend in Montreal, and mesured as you described. But I think he got confused on the issue and since then he hasn't had acces to the inclinometer. Now he has snow and ice on the roof and will not be attempting any more adjustments or measurements until spring. In the meantime I am on a fact finding mission to be armed with as much information before the spring thaw. Come this spring my friend plans on starting from scratch and putting up a better pole mount that is aduqautelly supported. He will be measuring the motor face again with an inclinometer and subtract from 90 as you stated, last time he did this he had set the incorrect angle. One other thing he will be doing next spring is moving his dish 20 feet to the south on his roof, this will clear trees in the way to the east and allow him a full view of satellites on the arc far east to far west.

I have researched the "ITB DM45" motor, from what I have read everyone is saying it looks like the SG2100 and think the same Company (Moteck) manufactures both but just puts different ID plates on the motor. But I have not found a users manual for this motor or any specs to the motor tube bend. The users manual for the SG2100 plainly states to subtract the declination angle from 30 degrees (30 degree tube bend). I have emailed and called several Companies inporting and selling this motor including itbusa, requesting a users manual or at the very least the specified angle for the tube bend, but never received a response. I am beginning to believe that there isn't a user manual for this motor.

His motorized dish problem would be a breeze to correct if I lived near him, but being several hundred miles away presents a big problem. Corrosponding through emails and sending photos is our best option. He just recently realized that you start aligment procedures by starting with the top of the arc (due south) satellite. Now because of the weather he will have to wait until spring.

 

[Wescopc]

I have researched the "ITB DM45" motor, from what I have read everyone is saying it looks like the SG2100 and think the same Company (Moteck) manufactures both but just puts different ID plates on the motor. But I have not found a users manual for this motor or any specs to the motor tube bend. The users manual for the SG2100 plainly states to subtract the declination angle from 30 degrees (30 degree tube bend). I have emailed and called several Companies inporting and selling this motor including itbusa, requesting a users manual or at the very least the specified angle for the tube bend, but never received a response. I am beginning to believe that there isn't a user manual for this motor.

His motorized dish problem would be a breeze to correct if I lived near him, but being several hundred miles away presents a big problem. Corrosponding through emails and sending photos is our best option. He just recently realized that you start aligment procedures by starting with the top of the arc (due south) satellite. Now because of the weather he will have to wait until spring.

There were SG2100's built with a 40° angle tube - see page 2 of this manual:
http://www.dmsiusa.com/documents/Manual SG2100 New1.pdf
so there is no absolute way of knowing the correct setting of the dish without knowing the angle of the tube on the motor you are installing! I have in the past gone to great lengths to help a motor install by email, I now have less hair.
Bob

 

[walrus1957]

Wscopc-

Thanks for the link to the SG2100 motor specs. I came across this some time ago, but when you need the link you can't find it again. I new the earlier versions of the SG2100 had a different motor tube bend other than 30 degrees.

I am begining to think that the DM45 is the early version of the SG2100 and has the tube bend of 40 degrees. That also makes me feel a littlle beter about my friends setup. Begining to think more and more that he needs to tilt the motor down a degree or two, this would align 74W (top of the arc) to a dish elevation angle around 33 degrees and hopefully begin to track the arc. Currently he has the dish elevation set around 34+ degrees so that it tracks 87W to 123W, dish is still low around 129W and high east of 87W, that is if I remember the information correctly in my freinds last email.

Haven't losed any hair as yet, but it can be difficult at times.

Still waiting to hear from someone who has one of these branded DM45 motors. Makes me think there wasn't a lot of them sold with this tag.

 

[walrus1957]

A few days ago I was able to measure the motor tube bend of the ITB DM45 motor, it is 30 degrees. Thought I would post this in case someone else was is need of the information.

Walrus1957