My dish settings wrong but it works ?

[Darren Rainer]

Hi all, im going mad trying to figure out why my dish finds the satellites in the arc yet all the calculations are out by miles. Let me explain :
I have the following setup :
1.2M Channel Master dish with an offset of 22.6 degrees.
Jaeger SMR-128G H-H Motor.
The motor is sitting on a dead straight pole (checked with inclinometer.
My latitude is 50.957
My longitude is -0.1277

So if I follow the Jaeger manual then it says for my latitude of 50.957 then the Elevation angle=50.64deg and the declination=6.67deg.

The manual says set the mount azimuth to 0deg. and point the dish to True south.

Next set the Angle of the mount as follows :

Angle of mount = Elevation angle + Declination

which works out as 50.64 + 6.67 = 57.31 degrees.

Now place a inclinometer on the back of the dish and set as follows :

Angle of dish = elevation angle - offset angle of dish - delination angle.

which is 50.64 - 22.6 - 6.67 = 21.37 degrees


Now if I do all this I cant find the satellites but if I point my dish to true south and set my Angle of mount to 39 degrees and have the angle of dish at 8 degrees it works. I can move the dish from 28.2 degrees east to 15 degrees west and I get all the satellites in between with good strength. (note. buildings in the way set the these limits).

So whats going on ? The pole is straight in all directions (showing 0 degrees on my inclinometer). Why wont the calculations work yet my trial and error setting up does. I set my dish to true South which is 3.92 degrees West of magnetic South. Also Thor at 1W shows 1W on the motor mount markings when reciving a good picture from its transponder, so this must be aligned ok too.

Any ideas ?

 

[2cvbloke]

I think the old phrase comes to mind, if it's not broke, don't fix it...

Sometimes the manuals aren't correct and give misleading instructions so when you think you're doing everything right and end up frustrated, but it is usually the case that the manual is wrong...

Best thing to do is ignore the manual for now and go by your own settings...

 

[Darren Rainer]

Its just occured to me whats going on. My 28.2deg signal on a 1.2M dish is 70 per cent with 60 percent quality. Now it should be 100%. There are roof tops in the distance and the dish is aiming over the top of these roofs at my east extreme and the same at my west extreme. So therefore by setting my motor angle to 39 degrees instead of 57degrees then the dish track does not drop off so rapidly on east and west extremes. This means the dish is looking above roofs at 39deg setting where if it is set correctly to 57deg then it would not clear the roof tops. I think that makes sense of things ? So answer is to get a longer pole on my patio mount. It's a shame I had to write a post on here in order to kick my brain cell into action.:-slaphead

 

[johnsattuk]

round figures cos it's easier

Elevation angle for motor = 90 - 51 = 39deg

dish angle = dish offset + declination = 23 + 7 = 30deg

dish face angle from vert. = 39 - 30 = 9deg

 

[Darren Rainer]

Sorry for late reply. Many thanks John, it all makes sense now. The manual forgets to say that you subtract the measured angles from 90 degrees.
Cheers
Darren

 

[Manikm909]

im having a nightmare realigning my SMR128 ever since the winds a few months back
i just cannot get it as spot on as i had it.
im sure i'll get there...
setting motor to 39 does not help me, more like 51

 

[jeallen01]

Sounds like the g/b has jumped, or even stripped a few teeth in the gear train - if it's anything like the NEC/Jaeger unit I had then some/all of those were nylon.,

OTOH, I thought you said you have a 99 Gold???

 

[Manikm909]

Sounds like the g/b has jumped, or even stripped a few teeth in the gear train - if it's anything like the NEC/Jaeger unit I had then some/all of those were nylon.,

OTOH, I thought you said you have a 99 Gold???

i have a couple of smr-99's doing nothing in the garage, i also have a spare 128G which if what you say is the case and my current one is buggered (i didnt even contemplate that) - i might be commissioning it soon

 

[Lazarus]

^^^^^^^^^^^^^^^^^^


You chaps do realise this Thread was last used sixteen years ago?

 

[Manikm909]

hey its still on-topic, even if the last post was a few years back - shows how good some of these motors are...

 

[Manikm909]

did u ever get it aligned mate

Can anybody identify this motor?

Hi, The motor on the attached picture came with the bundle I picked up on saturday but unfortunately the label is unreadable. It looks like a Jaeger 1224 one but being unable to find what model it is, I'm finding hard to figure out how to align it. Can anybody please identify if possible? Thanks!

www.satellites.co.uk

 

[Manikm909]

im having a nightmare realigning my SMR128 ever since the winds a few months back
i just cannot get it as spot on as i had it.
im sure i'll get there...
setting motor to 39 does not help me, more like 51

i just spent a worthwile 45 mins tinkering with the 1.2 - finally managed to tweak setup for 16.5db 42e & 30w - and 15.5db on 1w - "that'll do for me Patrick"

 

[jeallen01]

So what did you actually fix/ change /adjust??

 

[Manikm909]

So what did you actually fix/ change /adjust??

unbolted motor on pole - moved it round a bit to the west position - let signal drop - then tighten up a bit - as i tightened made sure it was staying plumb - then adjusted dish angle to peak on 1w - and everything fell into place!

will deffo mark positions and take some measurements after work

i've been up and down on and off for months! today was a good day.

 

[jeallen01]

Makes sense as the storms pushed the motor round the pole - remember that for the next time it happens (it will)!

PS: would have been the first thing I'd have thought of after all those storms

PPS: put a thin paint line across the pole clamp and the pole. Then, next time it happens, you'll see it and know where to swing it back to to correct the problem

 

[Manikm909]

Makes sense as the storms pushed the motor round the pole - remember that for the next time it happens!

PS: would have been the first thing I'd have thought of after all those storms

i will deffo remember ! i will also mark the points on pole with some kind of paint.

 

[jeallen01]

i will deffo remember ! i will also mark the points on pole with some kind of paint.

Next "weakest points" will be the clamps that secure the pole to the wall brackets, so mark those as well in case the pole slips around in those clamps.

Best thing to do is to use some sort of straight edge and spray paint as that will give a straight line to reset to.

PS: I often also do the same to the clamp that secures the dish to the motor arm, and then to the clamps that secure the motor to the pole bracket -> reset lines if the declination or elevation setting on one or other gets somehow out of correct position.

 

[Manikm909]

i just sent 1.2m dish to 52e - and WOW - 21db on IFILM2 - 10753 H 2500

and i thought the dish was properly aligned before!!!! 45 seemed to be the magic figure ....