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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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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.
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Chip Louie - Chief Daydreamer Imagination Hardware
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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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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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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?
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Brendan
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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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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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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.?
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Brendan
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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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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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One reason, old school, is to time a star moving across an
eyepiece to calculate field of view, if I remember correctly.
Ken
On 8/13/2020 9:25 AM, David C.
Partridge wrote:
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Why do you
want to stop RA traking surely the object will rapidly drift
out of view?
?
D.
?
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Another is to time the movement across a pair of crosshairs to calculate the separation of a binary pair.
?
Lately I turn off tracking, watch some TV and go back out without worry of the scope hitting the mount.
?
BG
?
Sent from for Windows 10
?
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From: k warren
Sent: Thursday, August 13, 2020 4:48 PM
To: [email protected]
Subject: Re: [Losmandy_users_io] How to pause a 492 digital drive
?
One reason, old school, is to time a star moving across an eyepiece to calculate field of view, if I remember correctly.
Ken
On 8/13/2020 9:25 AM, David C. Partridge wrote:
Why do you want to stop RA traking surely the object will rapidly drift out of view?
?
D.
?
?
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Hi John
here's a quick synopsis of stopping the 492 drive output electronically.
IC U2 (MIC58001) pin 1 (CLR) and 22 (/OE)are connected together and held "low" in normal operation.? This "low state" function allows the IC to provide drive outputs when /OE is "low".? Aka the stepper works.
/OE is provided by IC U3 (MC3847 Line driver) pin 10 (3Y) going "low" when commanded by other circuitry. ??
So, what you ideally want to do is change this
state on IC 2 pins 1 and 22 to a "high" but no damage U3!?? This would be best done thru a steering transistor/FET/diode/or electronic sw.?
Actually ?no, a logic OR gate would be easier! Added Drive SW (On HC) OFF = low as input yo one leg of iOR gate. Other OF Zgate leg input input ?low from U3. This OR OP = low Out. This U3 is /OE
Now ?activate added SW to HC to give a high out ?The OR ?will flip state to opposite to /OE now a high meaning it’s drive is off ?
?This would that allow normal /OE? normal functional operation but allow us to to change this to a "high" by activating an added button (in the HC) that switches this and a sml OR gate IC. Should even be simpler ways with guides and resistors?
Ideally you need to change the HC RJ 6 pin to an 8 pin (RJ45).? The PCB indeed has 8 pads and holes already its just they only fitted the 6Pin version (left the outer pins unconnected)...but you can change this.? This would allow you to add another switch into the HC and run its wires as needed thru the 8P8C RJ45 plug socket to the circuit that switches/OE.?
However you would need to ensure you wire this and the old pins to the correct existing positions....not change them to the wrong pin place.?
It can be done I haven't gone too deep into it and of course....if you do pursue it I cannot be held responsible for anything that goes bad.? It would be up to you top decide.? Sure it can be done.? There are fine details to design the switching "state" without damaging? U3 but his can be done.? U2 state just follows that pin 10 U3 commands it to.? A "high" /OE stops all output of U2, aka it stops Ra and DEC drive.?
Brendan
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While I appreciate the theoretical interest, the luddite in me still asks, what is gained by inhibiting the RA motor output, vs. just shutting off power to the 492?
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Show quoted text
[Edited Message Follows] Hi John
here's a quick synopsis of stopping the 492 drive output electronically.
IC U2 (MIC58001) pin 1 (CLR) and 22 (/OE)are connected together and held "low" in normal operation.? This "low state" function allows the IC to provide drive outputs when /OE is "low".? Aka the stepper works.
/OE is provided by IC U3 (MC3847 Line driver) pin 10 (3Y) going "low" when commanded by other circuitry. ??
So, what you ideally want to do is change this
state on IC 2 pins 1 and 22 to a "high" but no damage U3!?? This would be best done thru a steering transistor/FET/diode/or electronic sw.?
Actually ?no, a logic OR gate would be easier! Added Drive SW (On HC) OFF = low as input yo one leg of iOR gate. Other OF Zgate leg input input ?low from U3. This OR OP = low Out. This U3 is /OE
Now ?activate added SW to HC to give a high out ?The OR ?will flip state to opposite to /OE now a high meaning it’s drive is off ?
?This would that allow normal /OE? normal functional operation but allow us to to change this to a "high" by activating an added button (in the HC) that switches this and a sml OR gate IC. Should even be simpler ways with guides and resistors?
Ideally you need to change the HC RJ 6 pin to an 8 pin (RJ45).? The PCB indeed has 8 pads and holes already its just they only fitted the 6Pin version (left the outer pins unconnected)...but you can change this.? This would allow you to add another switch into the HC and run its wires as needed thru the 8P8C RJ45 plug socket to the circuit that switches/OE.?
However you would need to ensure you wire this and the old pins to the correct existing positions....not change them to the wrong pin place.?
It can be done I haven't gone too deep into it and of course....if you do pursue it I cannot be held responsible for anything that goes bad.? It would be up to you top decide.? Sure it can be done.? There are fine details to design the switching "state" without damaging? U3 but his can be done.? U2 state just follows that pin 10 U3 commands it to.? A "high" /OE stops all output of U2, aka it stops Ra and DEC drive.?
Brendan
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i saw some suggestions for uses previously, but i'm also thinking you could just insert a power switch? :)
On Fri, Aug 14, 2020 at 8:41 AM Les Niles < les@...> wrote: While I appreciate the theoretical interest, the luddite in me still asks, what is gained by inhibiting the RA motor output, vs. just shutting off power to the 492?
[Edited Message Follows] Hi John
here's a quick synopsis of stopping the 492 drive output electronically.
IC U2 (MIC58001) pin 1 (CLR) and 22 (/OE)are connected together and held "low" in normal operation.? This "low state" function allows the IC to provide drive outputs when /OE is "low".? Aka the stepper works.
/OE is provided by IC U3 (MC3847 Line driver) pin 10 (3Y) going "low" when commanded by other circuitry. ??
So, what you ideally want to do is change this
state on IC 2 pins 1 and 22 to a "high" but no damage U3!?? This would be best done thru a steering transistor/FET/diode/or electronic sw.?
Actually ?no, a logic OR gate would be easier! Added Drive SW (On HC) OFF = low as input yo one leg of iOR gate. Other OF Zgate leg input input ?low from U3. This OR OP = low Out. This U3 is /OE
Now ?activate added SW to HC to give a high out ?The OR ?will flip state to opposite to /OE now a high meaning it’s drive is off ?
?This would that allow normal /OE? normal functional operation but allow us to to change this to a "high" by activating an added button (in the HC) that switches this and a sml OR gate IC. Should even be simpler ways with guides and resistors?
Ideally you need to change the HC RJ 6 pin to an 8 pin (RJ45).? The PCB indeed has 8 pads and holes already its just they only fitted the 6Pin version (left the outer pins unconnected)...but you can change this.? This would allow you to add another switch into the HC and run its wires as needed thru the 8P8C RJ45 plug socket to the circuit that switches/OE.?
However you would need to ensure you wire this and the old pins to the correct existing positions....not change them to the wrong pin place.?
It can be done I haven't gone too deep into it and of course....if you do pursue it I cannot be held responsible for anything that goes bad.? It would be up to you top decide.? Sure it can be done.? There are fine details to design the switching "state" without damaging? U3 but his can be done.? U2 state just follows that pin 10 U3 commands it to.? A "high" /OE stops all output of U2, aka it stops Ra and DEC drive.?
Brendan
-- Brian?
Brian Valente portfolio
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Yea it looks like an RA power interrupt switch on the hand controller is the ticket. Allowing it to track on an alt/az mount moves the object out of the fov faster than if it was off.
Anyway the 492 works pretty nice with encoders, nexus, and sky safari 6. Manual controls induced hesitation, stuttering and backlash. Not to mention the 492 keeps my hands off the mount.
Thanks Everybody,
John
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Another idea to consider:
I thought that the autoguider or motor motion in RA rate of 1X just shuts off the RA motor if it is trying to "slew" in one direction, else 2X sidereal in the other direction.? ? If so perhaps there is a software approach to having RA stand still...
Have fun, Michael
On Fri, Aug 14, 2020, 3:21 PM John Desbiens via <jdlittlewing= [email protected]> wrote: Yea it looks like an RA power interrupt switch on the hand controller is the ticket. Allowing it to track on an alt/az mount moves the object out of the fov faster than if it was off.
Anyway the 492 works pretty nice with encoders, nexus, and sky safari 6. Manual controls induced hesitation, stuttering and backlash. Not to mention the 492 keeps my hands off the mount.
Thanks Everybody,
John
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On Fri, Aug 14, 2020 at 08:41 AM, Les Niles wrote:
While I appreciate the theoretical interest, the luddite in me still asks, what is gained by inhibiting the RA motor output, vs. just shutting off power to the 492?
Throwing the slide switch is going to disturb the mount. But I see no reason a normally on (closed) momentary switch can't be wired into the power switch and be used to cut power when desired.?
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Chip Louie
David C. Partridge
Michael Herman