Accuracy of actuator pulse count sensors on KU

[boomer_106]

My equipment list is in my sig line. I was wondering what you guys with a big dish and KU experience for accuracy on KU when changing satellites? Often times I have to tap the east or west button after landing at a satellite. This is on KU only. It lands on the C band satellite very reliably. I read the troubleshooting tip at skyvision. tip #6 on this page.
C-band Satellite Troubleshooting

I see the sensor wears out over time. I'm wondering since it's only off about 3 or 4 taps if replacing this sensor will help? If I still had C band only, I would never even notice it.

 

[Anole]

a few guesses

Why don't you pick your far east bird and your far west bird, and give us their locations and the number of counts between 'em?
(Oh, and your location, too)
There have been some posts which lead me to wonder if such troubles may be related to low or inaccurate counts.
Especially when adding Ku to an otherwise stable C-only BUD.

If you are missing counts, ya might take a look at the magnet and reed switch (if that's what you have) and see if they could be moved a little closer together.

How long have you been running?
That is, how long have you been off-count?
Did you reset the counting in the last month? Last year?
Five years ago and not since?
Do you move the dish often?

 

[Hermitman]

Before I'd consider sensor replacement, I'd be looking at more likely causes. Are the actuator mounting bolts or mounting points worn? Is the dish pivot point worn? Is the dish and actuator freely moving and not corroded? Is there slop in the actuator shaft? You can try checking by grabbing the edge of the dish and pushing or pulling it. If it moves, hunt down the looseness. Good luck.

 

[boomer_106]

Thanks for taking the time to reply.

Anole, on AMC 6 my counter says 4713 on AMC 7 it's 5056. Location is just south of Chicago. It seems the count issue has worsened the last couple years. I constantly get a KU freq tuned in and reprogram that sat in the receiver only to find I have to do it again next time I move back to it. Finally, yes I move the dish fairly often.

Hermitman, I suspect you are right on. The middle mount on the actuator is quite worn and sloppy. I inquired from somewhere (sadoun I think) a little while back about if you could just buy that middle bushing but you can't. You have to replace the whole actuator. I thought this might be a problem but, then I saw that tip at skyvision so I decided to seek help. The dish and actuator does move freely.

Man, I didn't realize it looked so shabby til I took this picture

 

[truckracer]

Boomer, I sent you a reply to your PM to me. Mine is like that too. Everything on my dish is set up properly and all my stuff is brand new. I do have to bump the dish a click or two to peak ku after moving the dish a few times.

I think that is normal with the tight beamwidth of a 10' dish on ku.

 

[linuxman]

Anole, on AMC 6 my counter says 4713 on AMC 7 it's 5056.

That's only 343 pulses/counts from 72W to 137W. That works out to be about 10 pulses per 2 degree satellite. That's not much room for error.

When you add that to the slop in your actuator assembly I think that would account for the problems you are having.

You would need to fix the slop with whatever it takes, and might also look for an actuator that has more pulses per inch.

There are some threads written here in the near past about actuator counts and accuracy. His is one thread, and here is another.

Hope that helps.

 

[gabshere]

there is also a thread about replacing the worm gear bushing and i think several places sell the middle pivot ball/bushing i thought skyvision had one listed but it was for a 2" shaft and was costly.

it was discussed in one thread about arm counts and some new arms don't really have enough counts for a v-box III but i suspect the g-box would handle it better but have no way of knowing unless i bought one. Some new arms only count 30 or 32 counts per inch while some others like an older vonweise counts 48 per inch. the more counts a arm has the more accurate it will be. I asked Sadoun about his actuators and the counts per inch but never heard back , i guess i need to send an e-mail

EDIT: checked out Sadouns website and he has added information to the Actuator page about how many pulse per inch for each one...
Thanks Sadoun


another test i was going to do was add a second sensor to the actuator to effectivly double the counts .... but as of yet to try it. this will be one of my summer projects.

 

[boomer_106]

truckracer, thanks. I didn't know if you would see this thread and since you had virtually the same setup I wanted to make sure I found out how yours performs.


linuxman, thanks for those thread links. Good reading there. Were the problems you were having with just KU or also C band?

gab, It'll be good to hear how your second sensor works out.

Next time I need to buy an actuator I'll make sure to look for a high pulse count model.

Here is pic of my motor

 

[gabshere]

you can check and make sure that the sensor below the magnet wheel is as close as it can get. if there is a small space you can lightly pull it until it almost touches the wheel. also you can check the wires and make sure they all have good connections (at the motor and receiver).

EDIT: my sensor is more centered under the edge of the wheel ...if that whole board that holds the sensor slides down just a bit might help. but it probably has a holding track or something that board fits into.

yes i will make a post on the second sensor add-on

 

[linuxman]

linuxman, thanks for those thread links. Good reading there. Were the problems you were having with just KU or also C band?

In the VBox III thread, the problem was with both, but it stemmed from an actuator that only produced about as many counts as yours does.

That's what prompted me to start investigating.

 

[gpat]

Just a thought but can an additional magnet be added to double
the pulse count?Looks like it could have a hole drilled and epoxy
filled around the magnet.
Also wondering if any of the hardware from a crank or cam sensor
out of a late model auto could be used.

 

[linuxman]

Just a thought but can an additional magnet be added to double
the pulse count?

Unknown to me at the time, the actuator I was using had a single magnet and was called a VW-24LC, the LC stood for low count.

I called Von Weise and they sent me out a pair of matched magnets so I could put them in. It did double the counts on my actuator, so depending on the actuator it is possible.

 

[boomer_106]

My actuator is a Superjack XL H8 pro brand international. Motor is QARL 3024+

 

[truckracer]

boomer,
You have the same exact motor I have. Mine is a 36" model.


Even my SG-2100 on a 76 cm patriot ku dish loses position after you move it around some.