Jaeger 1224 Installation Questions

I was thinking the same but in the pic of johnsatuk he has a triangular bracket with the motor on an angle but the dish is almost vertical. Is there a reason why johnsatuk has the motor set at an angle then a plate fitted to make the dish almost vertical. Why not do away with the plate and make the motor parallel with the dish.


wod said:
i was hoping to use just the plate as the elevation of the dish i don't think need all that much once the motor elevation is set correctly like in the pic of johnsattuk

i wonder if they are for prime focus dish or something
 
wod said:
i was hoping to use just the plate as the elevation of the dish i don't think need all that much once the motor elevation is set correctly like in the pic of johnsattuk

i wonder if they are for prime focus dish or something

A prime focus dish would not need them, since the dish angle is something like 25deg from vertical. Might even need them at the bottom.
 
TJExcalibur said:
I was thinking the same but in the pic of johnsatuk he has a triangular bracket with the motor on an angle but the dish is almost vertical. Is there a reason why johnsatuk has the motor set at an angle then a plate fitted to make the dish almost vertical. Why not do away with the plate and make the motor parallel with the dish.

As I said previously, the motor must be mounted at the correct angle for your lat. if you are going to track the arc.
 
:) OK its like this then. If the motor is parallel to the dish it would not be possible to track the arc. So the brackets allow the motor to be set at the correct angle and the brackets are the adjustment for the offset dish. Must admit I am unable to see the difference but the proof of the pudding etc......

johnsattuk said:
As I said previously, the motor must be mounted at the correct angle for your lat. if you are going to track the arc.
 
TJExcalibur said:
:) OK its like this then. If the motor is parallel to the dish it would not be possible to track the arc. So the brackets allow the motor to be set at the correct angle and the brackets are the adjustment for the offset dish. Must admit I am unable to see the difference but the proof of the pudding etc......

If your motor is horizontal, it will track a straight line in the sky, which if you were lucky may possibly pass through two sat. positions. :confused:

If you were on the equator, you would need to set your motor to vertical, pointing due south or north since you are in nomans land, and set your offset dish leaning backwards about 25deg (average sort off ofset for dishes) and you would then be able to track the sats.

As you are not at the equator, you need to set your motor to suit the lat. you are at, pointing due south when at the zero position.

You need to apply a correction for the curvature of the earth, (about 7deg for these latitudes) added to the offset angle of the dish. This gives typically 7deg + 25deg = 32deg. You then need to tilt the dish forward 32deg. This is approx the same as the inclination of the motor, and is why the dishes are close to vertical when at the top of the arc.

The dish will then track the arc, and will automatically apply the right amount of skew to the LNB and dish

The two things which can be measured and must be set accurately are the inclination and due south. Because of manufacturing tolerances, difficulty in measuring/knowing the offset of the dish, mounting position of LNB etc. some degree of fine tuning is usually required when finally setting up, but if you have set the motor accurately, all adjustments should be on the dish mounting. :)
 
Table of corrected inclination/declination
 

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so the jaeger is similar to diseqc motors then as i have set mine set to 53 latitude which is about 37 degrees for my location and then adjust the dish on thor with a satellite meter.

just the instructions with the motor make it unclear
 
wod said:
so the jaeger is similar to diseqc motors then as i have set mine set to 53 latitude which is about 37 degrees for my location and then adjust the dish on thor with a satellite meter.

just the instructions with the motor make it unclear

As long as the dish rotates on an axis at the correct angle for the lat. , is set up so that it points due south and the dish is given the correct declination, it will follow the arc.

The dish does not know or care if it is driven by a diseqc motor, a 36v motor, a Jack, a windscreen wiper motor or by hand, anything that moves it to the correct pos. is OK. :)
 
:) Now that is clear and you obviously know it will save me bolting the dish direct to the motor and then find it doesent work and having to take it off and fit the brackets. Maybe, with a bit of luck and if the weather stays fine I could have my first glipses of pics on my TV, Thanks for the advice and patience. :-worship

johnsattuk said:
If your motor is horizontal, it will track a straight line in the sky, which if you were lucky may possibly pass through two sat. positions. :confused:

If you were on the equator, you would need to set your motor to vertical, pointing due south or north since you are in nomans land, and set your offset dish leaning backwards about 25deg (average sort off ofset for dishes) and you would then be able to track the sats.

As you are not at the equator, you need to set your motor to suit the lat. you are at, pointing due south when at the zero position.

You need to apply a correction for the curvature of the earth, (about 7deg for these latitudes) added to the offset angle of the dish. This gives typically 7deg + 25deg = 32deg. You then need to tilt the dish forward 32deg. This is approx the same as the inclination of the motor, and is why the dishes are close to vertical when at the top of the arc.

The dish will then track the arc, and will automatically apply the right amount of skew to the LNB and dish

The two things which can be measured and must be set accurately are the inclination and due south. Because of manufacturing tolerances, difficulty in measuring/knowing the offset of the dish, mounting position of LNB etc. some degree of fine tuning is usually required when finally setting up, but if you have set the motor accurately, all adjustments should be on the dish mounting. :)
 
TJExcalibur, how far have you got with it all ? is it now setup and working ?
 
:confused: No. LNB holder came, set up th dish, well it can't be correct, got a strong signal on the meter, set it all up in front of TV and only get good signal 78%, quality 2%. I havent got a small TV with scart to put upstairs to see it all when moving the dish. Will have to move the heavy 32" up there. Plus, spend some time trying to figure out the dish settings, lnb skew and nearest satelitte again. Ive messed us somewhere so will even check all the connections tomorrow. Bit disappointing after ages of hard work with cables in trunking all nicely clipped etc. Would have been nice to have seen just one TV channel.....Ah well, tomorrows another day. O-zzz
:) David at Sat Super is giving me a carriage costs refund and apoligised for the TNT cock up. Invoice in the post...I hope.

wod said:
TJExcalibur, how far have you got with it all ? is it now setup and working ?
 
what sat you aligning up at as thor should be very strong on a 1.2m dish

bbc world on 11325 H, 24500, 7/8 which i use to align to

which meter are you using ?

you could slacken the adjustment bolts on the motor and see when the dish is tilted down or up the signal gets better ?

also the feedhorn if using one have you adjusted this for best signal ?
 
:mad: I spent all day on checking everything from scratch. Alingment of the pole, compass setting, elevation etc. Even checked the cable plugs.
Still signal strength 72% to 89%. Quality is 2% and does not alter. I think its the LNB so will try again Friday with a cheap one to see. The meter readings alter when I used it and I set the dish on that but still same results on receiver. U-zzz


wod said:
what sat you aligning up at as thor should be very strong on a 1.2m dish

bbc world on 11325 H, 24500, 7/8 which i use to align to

which meter are you using ?

you could slacken the adjustment bolts on the motor and see when the dish is tilted down or up the signal gets better ?

also the feedhorn if using one have you adjusted this for best signal ?
 
TJExcalibur said:
:mad: I spent all day on checking everything from scratch. Alingment of the pole, compass setting, elevation etc.

Did you allow for magnetic deviation on the compass. :)

'Dishpointer.com' is brilliant for showing where to aim, both for due south and the sat. positions . :)
 
:confused: I set the elevation to 39 degrees and went a several degrees either side. Not sure where I got 39 from, been reading so much stuff but looking at Dishpointer it says Elevation:31.8°. Sod me......sent the LNB back but it least it will get tested and its only a few quid postage. Will have another try Friday......:)



johnsattuk said:
Did you allow for magnetic deviation on the compass. :)

'Dishpointer.com' is brilliant for showing where to aim, both for due south and the sat. positions . :)
 
39 degrees elevation on the motor ?

the 39 degrees is that based on your latitude as you should set the motor to that if it correct for your area
 
TJExcalibur said:
:confused: I set the elevation to 39 degrees and went a several degrees either side. Not sure where I got 39 from, been reading so much stuff but looking at Dishpointer it says Elevation:31.8°. Sod me......sent the LNB back but it least it will get tested and its only a few quid postage. Will have another try Friday......:)

Dishpointer gives Lat. for Bournemouth as 50.723deg, looking at the modified table, this equates to about 51.5deg. this gives you your motor angle of 38.5deg (90 - 51.5). This is the angle which the motor must be at, only very small adjustments are permissible and are only to compensate for the difficulty in setting the angle accurately. You will not track many sats if this angle is wrong

The dish elevation given (31.9deg) is for a prime focus dish, not for an offset dish. It is sometimes referred to as the look angle of the dish. You need to subtract the offset angle of your dish from that figure

Dishpointer also shows due south, and the azimuth of a chosen sat. Often you can zoom in to see a landmark to aim at, even if it is another building, tree, road junction, neighbour's shed. :)
 
My Lat. is 52.5deg, corrected gives 53deg. giving motor angle of 37deg.

It is generally the motor angle we quote and measure because it is the easiest, (90deg - 53deg) but what we are really after is to get the turning axis to 53deg.
 

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Apologies for dragging up an old thread.

I've got a Andrews/ChannelMaster 1.2 dish and 1224 motor with the additional inclined orbit motor.

Can someone confirm my sums?

Results from dishpointer.com using Thor/Intelsat @ 0.8W as my south sat:

Site Lat: 53.5 degrees
Site Lon: -2.3 degrees
Dish Elevation: 28.9 degrees
Dish Azimuth: 181.2 degrees magnetic

So, I've found two tables for calculating the motor and dish declination angles. One table was part of the documentation I got with the motor. The other is the one posted by johnsattuk which is for a modified polar mount. I don't know which is the going to the right one.

According to the instructions supplied with the motor the figures are as follows:

Motor elevation: 35.83 degrees
Dish declination: 6.93 degrees

According to the modified chart table the figures are as follows:

Motor elevation: 54.15 degrees (although this could possibly be 90 - 54.15 which results in 35.85 degrees)
Dish declination: 6.92 degrees

Also, looking on the 'net has yielded another method for calculating these figures:

Motor elevation: 36.5 degrees (90 degrees - 53.5 degrees)
Dish declination: 6.3 degrees (28.9 degrees dish elevation - 22.6 degrees dish offset angle)

Which numbers are correct? This is all rather confusing. I've never set a motorized system up before. I've done plenty of fixed dishes in my time.

Also, could someone explain the declination aspect of the setup? My understanding is that figure (6 degrees) is subtracted from the motor angle (as measured with an inclinometer on top of the motor housing as per the photo in the previous post). But how should I measure this? Assuming the dish and motor are installed with the motor at the set angle, should I measure by placing my inclinometer on the metal plate on the back of the dish? If so, what angle should I be looking for bearing in mind I'm using an offset dish (the offset angle is reported to be 22.6 degrees for that model).

What I intend to do once I've figured out the correct motor and dish angles is to move my 1224 motor to 1.5 degrees east, loosen off the bolts on the pole and manually position the whole dish and motor assembly to get the best reception of Thor/Intelsat @ 0.8W. Once the dish is aligned correctly, I'll tighten all the bolts and then do a sweep of the arc and make sure I can see everything. Does that sound right?

Any info would be greatly appreciated.
 
The modified chart is a correction to compensate for the slightley non-spherical shape of the earth.

The motor angle and alignment to the south, sets the mount up to be aligned with the axis of the earth.

The declination angle sets the radius that the mount will describe at the equator ( clarke belt).

The dish offset angle means that the dish needs to be tilted forward by this amount, so that it also looks at the same radius. This will mean that your dish in the zero pos. (due south) will be leaning back slightly (35.8 - 6.9 - 22.6) 6.3 deg. Because of measuring dificulties, manufacturing tolerances etc. this will almost certainly need a little tweak when you get a sat to align on.

The figures supplied with the motor and the ones from the chart are very close to one another, I think it is unlikely that you would be able to set up these angles to 0.01 deg. , 0.1 deg is difficult in practice.

I would suggest use 35.9 deg. for the motor, set as accurately as you can, lean the dish back about 6 deg. and go from there. :)
 
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