Losmandy G11 problems

[Starcrazzy]

Hi all.

I recently purchased a losmandy G11 with gemini 2 from a member.
After building a pad and a shed for it I finally go it fired up.
Dissapointed is an understatement.
At first it wouldnt slew, it would start to but once the motors got up to full speed it would make a clicking noise and stop. The hand controller would say "back after power failure"
Now its not not tracking. It will track in "solar" divisions, but nothing else. It just doesnt move.
Has anybody got experience with the Gemini 2? Im starting to think ive been taken for bit of a sucker.

[E_ri_k (Erik)]

Sorry to hear, sounds strange? Have you tried updating the firmware to the latest version? I used to get motor stalls on my G11's RA motor. Turned out it was faulty. Had it replaced and all good. What power are you supplying to the mount, and what are you loading on it?

Erik

[Starcrazzy]

Hi erik. I havnt tried any serious fixes yet. Initially I was using the 12v/ ac/dc power supply that came with it. But now Im running it on a power pack. I only have a 110mm refractor on it ATM.
Its odd that it will track on solar divisions, and now its slewing ok. But just wont track.

[E_ri_k (Erik)]

Well it's not overloaded then. Strange that it won't track though. I'd maybe try troubleshooting it while using the AC power supply.

http://www.gemini-2.com

Do you know what firmware it is running? If you follow the link, you will find instructions on how to update the firmware.

I solved a few of my bugs with a firmware update.

[E_ri_k (Erik)]

Quote from the Gemini 2 page

"5. Back After Power Fail.
Gemini has a voltage supervisor on board that is primarily used to save all important data (positional, date, time) at power-off. This is necessary to allow for permanent PEC and Warm (Re)Start.
This supervisor triggers an interrupt if the voltage drops down below about 10V. All GoTo operations are stopped, motors are halted, Housekeeping is done, all files are closed.
G2 then enters a loop and waits for browning out (power off) or for regaining power. If power comes back the message "Back after power fail" is displayed and normal operation can proceed."

[Starcrazzy]

Thanx Eric. I think ive isolated the 12v power (AC) as the cause of the original stalling. Its slewing well now on the 12 v DC power tank. But still not tracking.
It will also track in celestial divisions. But not sidereal.

Havnt even tried an alignemnt yet if it wont track.

I looked at that site earlier. I dont think im up to the job, not a real computer tech, i couldnt even find the IP address for the gemini.

[el_draco (Rom)]

There is a lot of discussion about the power needed to run G11's. I had constant issues with stalling at 12V. Ramp it up to 15 and its a lot more stable. Firmware update is also important and relatively easy to do. Alas, the Gemini 2 software is still a work in progress and it frustrates me that users are the debuggers... Such is life.

[icytailmark (Mark)]

what power supply are you using? i use a 13.6vdc 5 amp powertech power supply and its been plenty to slew my c14 scope. The software might not of been updating properly by the previous owner. Go to this website http://www.gemini-2.com and do a full format of the sd card and upload the new updates. Make sure you carefully follow the instructions.

[mithrandir (Andrew)]

Get the Gemini Firmware Updater and use it to do the software upgrade.

The recommended and maximum voltage for running a Gemini is 18v. You can get a 60W 12v to 18v DC-DC converter as a special order from Snaptec. The part number is GB60-1218. Price around $AU200 with GST and postage. They also make a 12v to 15v that would work almost as well. Part number GB60-1215.

[Starcrazzy]

Ok..So..id be a clown wouldn't I.. Turns out, it was always tracking properly. i just didnt understand the HC and the info on it.
It tracks beautifully, and in sidereal rate too!!!

Sorry guys, thanx for the help tho.

[E_ri_k (Erik)]

Awesome to hear! Have fun with it
Erik