SG9120B motor near death

[northgeorgia]

I thought my dish or mount had somehow shifted, because I was no longer receiving any satellite east of 53W. Nope Turns out the motor is somehow limiting itself to about 51W. There are no enabled limits on the STBs (I tried 3 different ones), but each time it reaches that point, the LED on the motor turns red. It will move anywhere west of there, but refuses to go east. I'm even more concerned because I tried to do the reset sequence (unhook the coaxial to the STB, press both buttons simultaneously, then reconnect the coaxial; release after five seconds of restoring power). The result was nothing. No reset at all (usually this procedure drives the motor to the "0" position and clears any weird thing in its memory). Fortunately, I don't watch much past 53W, but I would have like to have tried for 30W once the leaves fall off this winter ... plus I'm worried about a total freeze-up with no reset. I'm not so mechanically inclined -- I read where one member discovered a damaged spring inside the motor.

Recommendations? New motor (*whine*)? I heard the one I had was pretty good, but is there something better out there with USALS?

 

[primestar31]

Did it used to go further for SURE?

If so, perhaps one of the internal limit switches has shifted in some way, so it now thinks that spot is the limit. You'd need to open it up, and look it over to see if you can adjust that.
I'd say it's worth at least cracking it open and observing how that works, and seeing if you can change it back if it's shifted

 

[northgeorgia]

Yep, for sure. I used to be able to watch TBN Enlace on 50W and RASD TV on 45W. I'm not mechanically inclined, but if someone had pictures of the guts of a motor and could show me what the internal limit switches look like (I didn't even realize there were in there!), I'd be willing to give it a go.

 

[primestar31]

There's some pics around here, I've seen them, do some searches and you should find them. I've never opened one so have no first-hand knowledge, but it shouldn't be too hard to look at the assembly, and figure out how it works, and if something looks "off". It'll probably be very obvious, such as a loose screw, and a micro roller switch moving back and forth, when it should be tight.

 

[gpflepsen]

I made a thread about a SG9120B teardown and rebuild. Look here: http://www.satelliteguys.us/threads/292212-Powermax-SG9120B-Teardown-and-Rebuild Some pictures show the limit switches. If I recall, it seems one limit switch indicates Center or 0 degrees and the other limits the extent of travel in one direction. I'd check the limit switch on the long cam to see if it'd backed away, but I can't see how that would cause what you're seeing. But it'd be easy to check.

 

[Anole]

I would be looking for a reset or mechanical cure.
However, if those both fail, I'd suggest the Stab HH90 motor.
Someone found it for around $69, and posted a vendor in a recent newbie or dead-motor thread.

 

[northgeorgia]

Thanks to radio in MI, I now have a Powertech DG-380 with the large tube. Unfortunately, I had to make a run to Home Depot to get some bigger hardware to mount the dish to it -- but as I like to play around with the mini-BUD project from time to time, I think it's worth it. I was worried I'd never get it finished as I raced against the clock. Positioning it took just 20 mins or so. It was the disassembly of all the bits and pieces off the dish to get those longer carriage screws into place Finally, I was tracking the arc securely before the twilight disappeared *whew*

I'm still going to see if I can get the sg9120b working again.

 

[radio]

Glad the motor arrived safely!
It's hard to trust shipping services for "care" of even heavy duty items like this anymore!
Enjoy, and thanks again!

 

[Cham]

I had my 9120B apart due to the same issues. It seemed to have some cold solder joints around the relay area that I think were the main trouble. Also the worm gear was bent a bit making the motor want to stall on every revolution. The latter was likely caused by severe weather, a dish too big, and too much wind. The limit switches are mounted above the main bearing on a bracket. They are easy to check with an ohm meter once the bracket (two screws) are removed. Might be wise to unplug the switches from the circuit board before testing just in case.