Re: How to pause a 492 digital drive
Put the slew/guide setting at 2X and pull the E pin to ground n the guider (aka ST4). That will shut off the RA.
Mark Christensen
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Re: How to pause a 492 digital drive
Why do you want to stop RA traking surely the object will rapidly drift out of view? ? D. ?
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From: [email protected] [mailto:[email protected]] On Behalf Of John Desbiens via groups.io
Sent: 12 August 2020 18:57
To: [email protected]
Subject: [Losmandy_users_io] How to pause a 492 digital drive ? [Edited Message Follows] Hi all,
I had a 492 for a G8 laying around and I just installed it on my AZ8. It really work great. Better then the slo-mo cables.
The only thing is once I center the object in the ep. and on sky safari, ?I'd like to stop the tracking altogether.
Any suggestions.
Thanks,
John
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Re: How to pause a 492 digital drive
I'm doing a circuit on this now but cannot release all the info due to CIC but can give enough to accomplish a task like this.
Give me a few days I'm almost done my cct.? I guess you could run it on the HC...Interesting thing here is the 492 PCB has holes for an 8 pin pin RJ HC socket but fitted a 6 pin RJ version.? There is one spare pin on the 6 pin RJ HC......(I think)....but even if not one could fit an 8Pin RJ and re-do this HC socket and plug to suit.
Sounds difficult but not really.
All that said.....one step is much more functional.? Yes I love the old 492 but one step adds things you that are much more modern.?
--
Brendan
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Hi Greg!
I'm pretty new around here, with a new mount.
But everything I've seen is American Standard size, thread, and pitch.
I haven't taken mine apart (nor do I plan to).
Scott's use of all American Standard fasteners was another of the things I found gave an authenticity?to it being American Made.
--
SonnyE
(I suggest viewed in full screen)
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Re: Issues With Initial GoTos on new GM811G
I, too, run a GM811G HD.
On occasion mine would go haywire and do a 180¡ã slew.
fixed the odd behavior. Which also requires you do your initial set up settings over again.
I will usually do my start up via menu just to make sure my previous settings are still sound.
That leaves me at a cold start anyway. But with the assurance everything is sound.
--
SonnyE
(I suggest viewed in full screen)
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Re: Issues With Initial GoTos on new GM811G
You are very welcome, Ryan.
I only got familiar with these "hidden" gear settings when I changed my gearboxes to McLennan metal ones, from the stock plastic version. The stock plastic ones were fine for many years, but one or two cases eventually cracked apart after a decade or so.? On the older systems I have, the motor hangs out the end of the gearbox and that weight might cause gearbox breakage.??
The metal gearbox version output shaft rotates opposite to that of the plastic type.? So in the Gemini system, you must select Custom mount, and then change the Worm setting from positive to negative.? That's why I got more deeply into those gear settings. Strangely, the gear settings are not documented in the Gemini manual.... I should write up a document for that.? I got them out of the Gemini itself using the Gemini.net Advanced panel display.?
Anyway, I'm quite happy as you are that you solved your riddle.??
The bigger riddle is: why was your new system not set up properly from the factory (if you bought it directly) or from your retail vendor?? Someone along the line should have tested it out before you received it.??Anyway, it is worth a phone call to your vendor, to help...the next person... (If you bought it from a place like Adorama ... call the factory who put the kit together.? Did it come with instructions on setting up the Gemini settings?)
Another puzzle to me is: that RA Worm setting should not have been negative.? I believe the MI (Mountain Instruments) -250 RA and Titan RA motor revolves in the opposite direction to the G11.? ? Gemini-1 mount settings default to Titan...hmmm maybe your Gemini-2 was still set to Titan not GM811???
?As I said when you change a major setting, park at CWD then reboot into a cold boot to get the settings into use.??
Have fun with your new GM811.!
Michael
Thanks Michael for this response.? I changed the values to the ones you stated in your post and this solved the issue.? First goto from CWD was almost in the field of view of my lowest powered eyepiece.? Once I aligned on it, i went to a number of objects in the same half of the sky without any issues at all.??
Ryan
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Re: Issues With Initial GoTos on new GM811G
Thanks Michael for this response.? I changed the values to the ones you stated in your post and this solved the issue.? First goto from CWD was almost in the field of view of my lowest powered eyepiece.? Once I aligned on it, i went to a number of objects in the same half of the sky without any issues at all.??
Ryan
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Re: How to pause a 492 digital drive
John,
Why do you need to stop it tracking?
Obviously, you could power it down or unplug the RA cable.
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[Edited Message Follows]
Hi all, I had a 492 for a G8 laying around and I just installed it on my AZ8. It really work great. Better then the slo-mo cables. The only thing is once I center the object in the ep. and on sky safari, ?I'd like to stop the tracking altogether. Any suggestions. Thanks, John
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Re: Issues With Initial GoTos on new GM811G
Hi Ryan, I had a similar?issue recently. I purchased a used G11 and I had a minor pointing issue, which caused me to replace the battery and do a firmware update. After that my pointing was much more problematic. I tried a bunch of different things, but what I kept seeing was my site and time information was not being stored, even after I just input the information. I could see the information was correct but the pointing was way off. What I found was that if you do not hit the store button on both the time screen, and the site screen, before returning to the go to screen, the information is lost.?
I did not read all the responses, so my suggestion may not apply in your case, but it is worth checking.?
James
On Wed, Aug 12, 2020 at 12:44 PM Michael Herman < mherman346@...> wrote: Hi...
Glad you wrote that detailed report!
Your RA worm gear is set incorrectly to negative, but should be positive.
That will change its rotation direction to be correct.
Note for the future:? If your mount had McLennan metal gearbox (not a stock item but an aftermarket change some people (like me) make), then ? you would need to have the negative RA Worm Gear value.? For the stock plastic gearbox, you would NOT need a negative value.
The correct values for the G11 RA section of your GM811 mount should be the same as for a stock G11 mount: ? ? ?RA Worm Gear:(G11size)? +360. (plastic stock gearbox. Negative for McLennan metal gearbox) ? ?? ? ? ?DEC Worm Gear: (GM8 size) +180. (+ for plastic stock gearbox.? Negative for McLennan metal gearbox)
? ? ?For both axes...same values: ? ? ?Spur gear ratio:? 25? ? (that's the entire gearbox that is 25:1) ? ? ?Servo Encoder resolution:? 256 ? ? Steps per Worm Revolution:? 6400
? ? Manual Slew:? 800??
(many people reduce that to about 600 to put less strain on the motor)
? ?GoTo Slew:? 800? ? (many people reduce that to about 600 to put less strain on the motor)
Anyway, maybe someone had set up your Gemini-2 before you received it.? If you got it direct from the factory...it should be reported.? It should have been tested by whomever sold it to you.
Best regards, Michael
On Wed, Aug 12, 2020 at 11:33 AM Ryan Weiss < rrweiss14@...> wrote: So I just did a couple of trials to see if switching the settings to G811 would fix the issue.? It does not, but working on this in the light gives me a better idea of what is going on.? My post this morning was incorrect about what axis was having the issue, it was not declination, but RA? (I will fully admit to getting them confused sometimes).? It looks like what is happening, at least in part, is that the RA axis is moving in the wrong direction of rotation.? To put it another way, the RA axis rotated clockwise around the RA axis if viewed from the position of looking through the polar scope.? If the RA axis would have moved counterclockwise the same amount from the CWD position, I think the mount would be pointing very close to the location of the star I selected (Mizar).??
I've checked all of the location and time settings and they appear to be correct.? What could be happening to make the RA axis move in the wrong direction?? I have not changed anything in the Mount\Gearing menu, which has the following values:
RA Worm Gear: -270
DEC Worm Gear: 360
RA Spur Gear 50
DEC Spur Gear: 25
RA Motor Encoder: 256
DEC Motor Encoder: 256
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Re: How to pause a 492 digital drive
Brendan,
Sounds interesting. Can this interrupt switch be incorporated into the hand controller?
Any diagram or photo would be helpful.
Added a couple photos of what I'm up to.
Thanks,?
John
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Re: How to pause a 492 digital drive
Fixing a 492 drive atm. It¡¯s stepper driver has an Output Enable pin which can be used to stop output stepper drive. ?I¡¯m sure it¡¯s already digitally utilised but the. cct could be hacked with a resistor/gate/extra button to provide the function the OP wishes.
I¡¯m home today and can comment better when I look at the ccts. Indeed there is a set of ?unused ?Switch pads and IC inverter gates already on the circuit.....that could possibly accomplish this ?
Means installing a switch like the OEM (needs a hole for this in top case) wire IC gate to OE pin!
anyway FWIW?
--
Brendan
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Re: How to pause a 492 digital drive
Since the 492 isn¡¯t useful for slewing the mount any significant distance, and there¡¯s no calibration or model to worry about, turning it off works just fine. ?
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On 12 Aug 2020, at 14:08, Brian Valente < bvalente@...> wrote:
Chip is correct - there is no terrestrial?model (no tracking) or other way to stop tracking?on the 492 other than to power it off On Wed, Aug 12, 2020 at 12:50 PM Chip Louie < chiplouie@...> wrote: Hi John,
I'm pretty sure you are out of luck on that one. AFAIK there is no way to run off the RA tracking other then the power button.
--?
Chip Louie - Chief Daydreamer Imagination Hardware
--?Brian?
Brian Valente portfolio?
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Re: How to pause a 492 digital drive
Chip is correct - there is no terrestrial?model (no tracking) or other way to stop tracking?on the 492 other than to power it off
On Wed, Aug 12, 2020 at 12:50 PM Chip Louie < chiplouie@...> wrote: Hi John,
I'm pretty sure you are out of luck on that one. AFAIK there is no way to run off the RA tracking other then the power button.
--
Chip Louie - Chief Daydreamer Imagination Hardware
-- Brian?
Brian Valente portfolio
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Re: Changing limits caused "Target Unreachable" errors near the meridian
I think you want to set the limits to High values...> 90 (degrees). The limits are "measured" with respect to the CWD direction...i.e. near zenith.? A low limit limits you to be near CWD.? Always use a positive value for the limits.? They are available in Gemini.net in the Advanced panel, ...go there and play (in the daylight!)
Stay well,
I just got a larger refractor 110mm and decided to change my limits to avoid hitting the mount. After doing that I started getting "Target Unreachable" errors on anything near the meridian to the south.
What is the lowest number that you can use and still reach those targets.
Is there any place to see what the mount RA angle is currently and anyway to see what angle a target will require.
Is the only solution for bigger refractors a tripod extension to be able to use the default 114 and 123 values. These worked great with my C8
Rick
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Re: How to pause a 492 digital drive
Hi John,
I'm pretty sure you are out of luck on that one. AFAIK there is no way to run off the RA tracking other then the power button.
--
Chip Louie - Chief Daydreamer Imagination Hardware
|
Re: Issues With Initial GoTos on new GM811G
Hi...
Glad you wrote that detailed report!
Your RA worm gear is set incorrectly to negative, but should be positive.
That will change its rotation direction to be correct.
Note for the future:? If your mount had McLennan metal gearbox (not a stock item but an aftermarket change some people (like me) make), then ? you would need to have the negative RA Worm Gear value.? For the stock plastic gearbox, you would NOT need a negative value.
The correct values for the G11 RA section of your GM811 mount should be the same as for a stock G11 mount: ? ? ?RA Worm Gear:(G11size)? +360. (plastic stock gearbox. Negative for McLennan metal gearbox) ? ?? ? ? ?DEC Worm Gear: (GM8 size) +180. (+ for plastic stock gearbox.? Negative for McLennan metal gearbox)
? ? ?For both axes...same values: ? ? ?Spur gear ratio:? 25? ? (that's the entire gearbox that is 25:1) ? ? ?Servo Encoder resolution:? 256 ? ? Steps per Worm Revolution:? 6400
? ? Manual Slew:? 800??
(many people reduce that to about 600 to put less strain on the motor)
? ?GoTo Slew:? 800? ? (many people reduce that to about 600 to put less strain on the motor)
Anyway, maybe someone had set up your Gemini-2 before you received it.? If you got it direct from the factory...it should be reported.? It should have been tested by whomever sold it to you.
Best regards, Michael
On Wed, Aug 12, 2020 at 11:33 AM Ryan Weiss < rrweiss14@...> wrote: So I just did a couple of trials to see if switching the settings to G811 would fix the issue.? It does not, but working on this in the light gives me a better idea of what is going on.? My post this morning was incorrect about what axis was having the issue, it was not declination, but RA? (I will fully admit to getting them confused sometimes).? It looks like what is happening, at least in part, is that the RA axis is moving in the wrong direction of rotation.? To put it another way, the RA axis rotated clockwise around the RA axis if viewed from the position of looking through the polar scope.? If the RA axis would have moved counterclockwise the same amount from the CWD position, I think the mount would be pointing very close to the location of the star I selected (Mizar).??
I've checked all of the location and time settings and they appear to be correct.? What could be happening to make the RA axis move in the wrong direction?? I have not changed anything in the Mount\Gearing menu, which has the following values:
RA Worm Gear: -270
DEC Worm Gear: 360
RA Spur Gear 50
DEC Spur Gear: 25
RA Motor Encoder: 256
DEC Motor Encoder: 256
|
Changing limits caused "Target Unreachable" errors near the meridian
I just got a larger refractor 110mm and decided to change my limits to avoid hitting the mount. After doing that I started getting "Target Unreachable" errors on anything near the meridian to the south.
What is the lowest number that you can use and still reach those targets.
Is there any place to see what the mount RA angle is currently and anyway to see what angle a target will require.
Is the only solution for bigger refractors a tripod extension to be able to use the default 114 and 123 values. These worked great with my C8
Rick
|
Re: Issues With Initial GoTos on new GM811G
So I just did a couple of trials to see if switching the settings to G811 would fix the issue.? It does not, but working on this in the light gives me a better idea of what is going on.? My post this morning was incorrect about what axis was having the issue, it was not declination, but RA? (I will fully admit to getting them confused sometimes).? It looks like what is happening, at least in part, is that the RA axis is moving in the wrong direction of rotation.? To put it another way, the RA axis rotated clockwise around the RA axis if viewed from the position of looking through the polar scope.? If the RA axis would have moved counterclockwise the same amount from the CWD position, I think the mount would be pointing very close to the location of the star I selected (Mizar).??
I've checked all of the location and time settings and they appear to be correct.? What could be happening to make the RA axis move in the wrong direction?? I have not changed anything in the Mount\Gearing menu, which has the following values:
RA Worm Gear: -270
DEC Worm Gear: 360
RA Spur Gear 50
DEC Spur Gear: 25
RA Motor Encoder: 256
DEC Motor Encoder: 256
|
Re: Issues With Initial GoTos on new GM811G
On Thu, Aug 13, 2020 at 02:18 AM, David C. Partridge wrote:
Not all of UK is +ve Longitude ¨C the meridian passes through Greenwich, London.
?
Yes, of course you¡¯re totally right!? -- Brendan
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How to pause a 492 digital drive
Hi all,
I had a 492 for a G8 laying around and I just installed it on my AZ8. It really work great. Better then the slo-mo cables.
The only thing is once I center the object in the ep. and on sky safari, ?I'd like to stop the tracking altogether.
Any suggestions.
Thanks,
John
|
David C. Partridge
Michael Herman
James B
Chip Louie