New Ku band Project

[Chewie]

Hello Gents
I have started a new project is a 1.2m solid dish, Stab motor, non-penetrating mount that will go on top of my patio, I assembled it on the ground for testing and I am having problems.
According to the Stab instructions it should be set to my Latitude and is set to 34 degrees, now the dish instructions are for just a pole mount and top loading motor, the Stab motor is not a top loading motor, and it should be set for normal elevation, is this normal elevation the same as the Latitude? I set to my latitude 34 degrees.
I installed standard Ku band LNB on it, I am using the Dr HD meter on it, the problem I am having is that I do not get any signal at all, I have replaced the cables, bypass the motor and same problem, I went up and down on the elevation on the dish and still no signal, I installed a second Universal Ku LNB and the same problem, the dish is not warped it looks in very good condition, the arms and LNB arm are not damaged.
So I don't know where the problem is, I think is either the LNB's are no good or the dish elevation is not set properly.
Any Comments would be appreciated.
Thanks in advance.
Regards.
Chewie

 

[dl76]

Maybe it being under your patio roof?move closer to where there is nothing over top of dish.

Sent from my SM-G930V using Tapatalk

 

[Chewie]

I Tested the dish outside the Patio I took those pictures after the dish was assemble, it was raining at the time.

 

[comfortably_numb]

Chewie,

Good choice on the 1.2m Geosat dish. I also have that dish. I don't have the instructions sheet in front of me, but I believe the assembly on the back of the dish might not be correct. Maybe Titanium can weigh in

 

[Titanium]

The dish elevation scale setting will be the same as setting for a pole mount. The scale on the mount will be read as a normal button load pole mount.

According to the Stab install guide, what is the dish angle setting for your location?

How are you setting the dish elevation angle?

From the attached photos, I estimated the current aiming to be at a satellite elevation of approximately 60 degrees (35 degree dish face plus the offset angle of 26 degrees). Is that the angle of the satellite that you are targeting? Looks way too high for any satellite from California. My guess is that you are shooting at empty sky above the satellite.

 

[Chewie]

Hello Guys
My latitude is 34 and that is what I have on the motor and the same for the dish, I am aiming at 117 west Sat

 

[comfortably_numb]

Chewie, I think your elevation is too high. Start with 97 to lock a powerful TP.

 

[Chewie]

I will get it going I just never had a Stab motor before, Mainly I need to know the elevation of the dish.

 

[Titanium]

Hello Guys
My latitude is 34 and that is what I have on the motor and the same for the dish, I am aiming at 117 west Sat

Guess my guesstimate for the dish look angle was darn close!

For your location, the motor latitude should match your latitude. According to the calculation in the HH120 manual, the dish elevation angle scale setting should be approx. 24.5 degrees.

Yep, currently aimed about 10 degrees above the arc.

 

[clucas]

I never had too much luck using just the numbers. I would pick a Ku satellite closest to your longitude (maybe it’s 121 depending on where you are) and align your dish on a plumb pole without the STAB. Once you get that put the STAB back on pointing as north/south as you can and attach the dish. Leave the dish angle as is and only adjust the STAB angle until you get your signal back.

 

[a33]

For your location, the motor latitude should match your latitude. According to the calculation in the HH120 manual, the dish elevation angle scale setting should be approx. 24.5 degrees.

That's right. With motors like these the dish elevation scale should be on 'motor shaft bend angle' (for HH120 that would be 30*) minus 'declination angle for your location', so in your case (30 - 5.5) = 24.5*

You could also use 'modified motor angles', which track the arc a little better so would cost you less time for fine-adjustment.
For LAT 34 the modified angles are:
Mod LAT 34.6 (equals Mod motor ELEV 55.4); Mod DECL 4.9
Edit: In that case the dish elevation scale should therefore be on (30 - 4.9) = 25.1*.
(Notice that the motor angle is 0.6 different, but the declination also: so the motor axis stands a little forward, but the dish aiming south is in the same position as with 'traditional' angles.)

Good luck!

Greetz,
A33

 

[a33]

Leave the dish angle as is and only adjust the STAB angle...

So how would you get the motor track the arc, then?

If you leave the dish elevation as is, the motor axis should be set exactly parallel to the pole, or otherwise the dish wouldn't be pointing to the satellite anymore.
Not the condition, to track the arc, I guess...

greetz,
A33

 

[a33]

So how would you get the motor track the arc, then?

Thinking of this (I cannot change my post anymore):

If you're in luck that the bend in the motor shaft is equal to your motor elevation angle, then your ( clucas ) method is absolutely right!
Didn't think of this before.
In that case the upper end of the motor shaft ends up exactly parallel to the pole, at which the motor is attached (and at which the dish elevation is set, without the motor).

For the HH120 and HH100 (and also sg2100), you'd have to live exactly at Latitude of 60*, though (where 'traditional' motor elevation angle is 30 degrees).
For HH90, at LAT 45*
DG120: 50*
DG240: 55*

So it's not a very universal method, I would say...

greetz,
A33

Edited: I confused motor latitude and motor elevation values. Now corrected.

 

[raydio]

Hey Chewie I used this site DishPointer - Align your satellite dish It will give you all the info you need for your QTH specific for your motor.

 

[Chewie]

Guess my guesstimate for the dish look angle was darn close!

For your location, the motor latitude should match your latitude. According to the calculation in the HH120 manual, the dish elevation angle scale setting should be approx. 24.5 degrees.

Yep, currently aimed about 10 degrees above the arc.

Hello Brian
you were right on the money, the elevation of the dish was wrong, I set it to around 24.5 and got the signal and was able to scan a few channels from 117W, the motor is not tracking the Arc properly sat's are off so I have to fine tune it, well the dish is going on top of my patio and fine tune up there.
Thanks to all of you for your comments, I will post more pictures when is on top of the patio.
Regards
Chewie

 

[clucas]

Hi A33. My motor installation was over 15 years ago so my memory of it may not be good. All I know is my SG2100 tube pointed downward and it worked but later the unit died. Since then I’ve used two free Primestar dishes, a .76 and a 1.2 meter. Now my 1.2 has 3 lnbfs (103, 97 and 91) and the .76 has 2 (99 and 95) with a Primestar on 125. No more motor.

 

[Cham]

I have had an HH120 motor here for over 10 years, still going strong, but I did have to do some repairs to it due to a wind storm and main bearing getting loose. Mine has a latitude and elevation scale (one on each side), but they mean the same thing just have to - 90deg to get the other measurment...
Sounds like you are in the ball-park regarding aiming, takes some time to get them dialed in exactly. Quite rewarding to get it right. Good luck!

 

[Chewie]

Hello All
The dish is on top of my patio and the Stab motor is tracking from 125w to 87w I still need to fine tune it some more, is there anyway to speed up this motor is very slow but it tracks very good. I need to buy a good RG6 cable, what is a good brand?
Let me know.
Thanks in advance.
Regards.
Chewie

 

[raydio]

Hello All
The dish is on top of my patio and the Stab motor is tracking from 125w to 87w I still need to fine tune it some more, is there anyway to speed up this motor is very slow but it tracks very good. I need to buy a good RG6 cable, what is a good brand?
Let me know.
Thanks in advance.
Regards.
Chewie

Stab motors are slow and really are meant to be. With satellite spacing as close as 2 degrees you don't want overshoot. Also I don't think there is a way to speed them up.

 

[a33]

You could modify the motor and supply a higher (external) voltage to the motor-part. Don 't know if that causes overshoot; never tried it myself.

Ways to do that, see e.g in this post (and the entire thread, and also the linked threads in the post): Antenna motors - power consumption - SatsUK

greetz,
A33