Continuing woes with PHD

[seeker372011 (Narayan)]

Dear all:

Very frustrated with problems I am having-any suggestions most appreciated

for some reason, my CG5 has simply stopped autoguiding in Dec

I can see the problem when calibrating-West and Esat movement is fine, North movement' s fine , then the guide star refuses to move when PHD is trying to bring the star back to the cross hairs in South

the star moves fine in all directions when I try using the hand controller- no
discernible stickiness, at least in a 12mm eyepiece

Gotos and alignment are very good;

My polar alignment is good if not very good;

I have tried using the serial cable plugged into my hand controller and also
with a GPUSB (different cable and plugged into the ST4 port)-so it doesn't seem to be a cable problem

I have opened the mount up twice and tried to adjust the gears -they seem to run smoothly -smoother than before, far less backlash.

The scope is balanced slightly rear heavy

I cannot use this mount anymore-and I used to be able to take 20 minute
autoguided images routinely in the past. For the last few months every attempt has failed. I have tried various settings in PHD, but nothing seems to work

have tried with lighter telescopes, and heavier.Nothing.


Any advice most appreciated

[Tandum (Robin)]

There is a program on shoestring called gpusbcheck. It will let you knudge the scope via the gpusb device. Might be wise to get that and make sure it talks to the scope in all directions. You'll see the star move if it works.

http://www.store.shoestringastronomy...heck_setup.exe

[gbeal]

Or, like Robin is eluding, I have tried with the mount set to a high speed slew rate, and used the Manual Guide buttons in PHD. Connect it all up, and see if you can "move" or "slew" using these buttons. I do this each time I make a new cable, that way I know the signal is actually getting through. Can be done indoors, anytime.
Gary

[seeker372011 (Narayan)]

Thanks for the suggestions, I will try the manual guiding to see if it is moving

I don't think there is anything wrong with the GPUSB or cables-the same box and cable works just fine with my EQ6, so if there is something wrong it may be the innards of the mount's electronics

[seeker372011 (Narayan)]

tried the manual guiding

--no luck

can only go to 99% of sidereal as a max guide rate on my mount

cant tell by listening if it is working or not

got to wait for next weekend to try on some stars

[multiweb (Marc)]

Originally Posted by seeker372011

I don't think there is anything wrong with the GPUSB or cables-the same box and cable works just fine with my EQ6, so if there is something wrong it may be the innards of the mount's electronics

There is a utility that you can download from Shoestring Astronomy website called GPUSBCheck.exe. Run it on your system and check all is good. Once you have that ruled out try to move the mount with this same utility.

[Tandum (Robin)]

Originally Posted by gbeal

Manual Guide buttons in PHD.

There are manual guide buttons in PHD You learn something everyday

[gbeal]

Originally Posted by Tandum

There are manual guide buttons in PHD You learn something everyday

Yep, me too.
With the likes of the EM200, putting the H/N slew switch to "H", makes it slew wildly, and using the manual button means you c an almost see the mount move, certainly hear it move. This helps me with knowing the actual command is getting to the motor(s).
Not sure if Narayan can get his mount to "slew" quickly like this though, hope so?
Gary

[Omaroo (Chris Malikoff)]

cant tell by listening if it is working or not

Narayan - are you placing your ear directly on the motor casing when you are trying to listen? You won't necessarily hear the subtle speed change otherwise, as some motor/gearbox systems are louder than others. You're listening for an almost imperceptible change at guiding rates, not slewing speeds. I use the test to check cables and hand box too.

[seeker372011 (Narayan)]

Originally Posted by gbeal

Yep, me too.
With the likes of the EM200, putting the H/N slew switch to "H", makes it slew wildly, and using the manual button means you c an almost see the mount move, certainly hear it move. This helps me with knowing the actual command is getting to the motor(s).
Not sure if Narayan can get his mount to "slew" quickly like this though, hope so?
Gary

Unfortunately no... the maximum I can go is 99% of sidereal-and can neither see nor hear it move

Originally Posted by Omaroo

Narayan - are you placing your ear directly on the motor casing when you are trying to listen? You won't necessarily hear the subtle speed change otherwise, as some motor/gearbox systems are louder than others. You're listening for an almost imperceptible change at guiding rates, not slewing speeds. I use the test to check cables and hand box too.

unfortunately no--I tried can't make out a change even with my ear glued to the casing

got my son to give it a go-hoping younger ears would be more discerning-no luck or at least thats what he says maybe he just wasn't trying hard enough

Also

Originally Posted by Tandum

There is a program on shoestring called gpusbcheck. It will let you knudge the scope via the gpusb device. Might be wise to get that and make sure it talks to the scope in all directions. You'll see the star move if it works.

http://www.store.shoestringastronomy...heck_setup.exe

I actually have this program-had it all along, had forgotten about it

will give it a go and see if it helps

Thanks all for the suggestions

its when you have equipment troubles like like these that you feel like taking up a nice soothing hobby..stamp collecting anyone?



Narayan

[Tandum (Robin)]

Narayan, mine is doing the exact same thing at the moment. Star goes up, star comes down, star goes left but does not go right. PHD suddenly says GUIDING.

I've pulled all of the cables apart tonight and checked everything and it all looks good. I'm currently guiding with an 800mm scope and it's +/- 1 pixel in phd when running. Images are ok, I posted a couple, so it all must be working? Go figure .....

[seeker372011 (Narayan)]

Originally Posted by Tandum

Narayan, mine is doing the exact same thing at the moment. Star goes up, star comes down, star goes left but does not go right. PHD suddenly says GUIDING.

I've pulled all of the cables apart tonight and checked everything and it all looks good. I'm currently guiding with an 800mm scope and it's +/- 1 pixel in phd when running. Images are ok, I posted a couple, so it all must be working? Go figure .....

???
in my case though the graph suggests something is seriously wrong in Dec..since you have perfect stars maybe it means your polar alignment is so spot on it needs make no corrections in Dec and is guiding in RA only
(though I have to say I thought my polar alignment was scarily good on some occasions when I have had the problem)

I asked the question over on the Craig labs yahoo forum and others seem to have similar experience to you-star doesnt come back, but guiding is OK


??????