¿ªÔÆÌåÓý

Date

Re: Gemini 1 Failure Modes That Can Drain Internal Battery

 

Jeff

i??? Is it one with the CR2032 battery??

If "yes" .....the battery holder positive has 2 small "finger" clips that either one or both have a habit of getting caught under the battery, as a new battery is inserted.?? This shorts the battery positive to negative.? The result......your battery drains rapidly.? Seen this before, more than once.

Other than that there could be a bad SRAM IC (U9) or RTC IC (U2).? If this is true then one of them will be getting quite warm to finger touch.?

The battery can be fixed by bending the contact back up but might be best to send it to have the battery holder replaced.?? If its not the battery holder and is anything else.....needs to be sent for repair and a firmware update.? SRAM ICs are a known issue in failing easy enough to replace.?

Repairers for G1s are Michael Herman (USA), David Partridge (UK) and my self (Australia), contactable in this forum.? If you send it for a battery holder replacement ensure you tell the repairer so they have one waiting for replacement.

Cheers get back if you need any further help.?? All G1s are quite repairable.
--
Brendan


Gemini 1 Failure Modes That Can Drain Internal Battery

 

Basically, what the title asks.

I have an older Gemini 1, L1.02 control unit.? It seems to go through batteries, draining them in a matter of minutes, getting CMOS resets only minutes after changing the battery out.? But the unit works fine immediately after a battery change, even when quickly rebooted after the battery change.? Then, after being shut down for maybe 10 minutes, upon power up I get those normal "......"'s then an "X" before the display begins the start up scroll and a CMOS reset happens.? Once the mount and location data is reloaded, everything works fine.? Just don't shut it off.??

If this is indeed a known with some units, can it be fixed?

Jeff


Re: G11 with Gemini2 issues with Go To

 

Hi Brian, I followed your instructions and out of about 20 times, once it pointed correctly. I have tried inputting the information myself, and allowing the GPS to input the data. I also tried resetting the handset as shown in your videos, and still noting different. When it points it looks like it is about 7 or 8 hours off. I tried adjusting the GMT time to 00:00, and that did not work either.

I also checked the battery with my volt meter and it was reading 3.03 volts, same as the original that I replaced recently. So, I replaced it with another brand new one that was at 3.29 volts.

I will still need some help, if you don`t mind.

James


Re: RA spikes towards west

 

O.M.G.
PEC spikes!!!
I'd never ever guess that one!

So many Sci Fi movies have the same theme: glitches in the machine code.? From Westworld to.... you name it.??

I was also thinking of the great movie Forbidden Planet and the "monsters of the Id".... Maybe your Id monster turned in the PEC checkbox?!

So happy you solved your spikes issue.

Stay well, Magnus!

Michael



On Tue, Aug 4, 2020, 2:15 PM Magnus Larsson <magnus@...> wrote:
Hi!

Michael :)

> Given all that you have done, I doubt it is the mount drive...

Thanks. I was only thinking mechanics. But there are other things. And
what might cause problems when you're not thinking of it?

PEC

Turns out, I had PEC turned on. But it should be off. As I am fiddling
with the mount, I have no good PEC curve for the moment. But it was on.
That d***ed "Turn PEC on on boot".....

Now PEC is off. And so are the spikes. Mystery solved, it seems :)

A very happy

Magnus





Re: RA spikes towards west

 

Hi!

Michael :)

Given all that you have done, I doubt it is the mount drive...
Thanks. I was only thinking mechanics. But there are other things. And what might cause problems when you're not thinking of it?

PEC

Turns out, I had PEC turned on. But it should be off. As I am fiddling with the mount, I have no good PEC curve for the moment. But it was on. That d***ed "Turn PEC on on boot".....

Now PEC is off. And so are the spikes. Mystery solved, it seems :)

A very happy

Magnus


Re: Forgot to introduce myself

Sonny Edmonds
 

Hi James,
Welcome to the group!
There are a lot of guys here from around the world that are well versed in Losmandy Mounts going way back.
So you came to the right place.
--
SonnyE


(I suggest viewed in full screen)


Re: RA spikes towards west

 

¿ªÔÆÌåÓý

Hi!

This clearly affects my imaging. The spikes produce doubled stars, so to speak. Subs not usable. So it needs to be fixed.

I totally agree on the slightly wiggly-jiggly graphs :) But this one needs fixing.

Magnus


Den 2020-08-04 kl. 21:54, skrev Sonny Edmonds:

How is your imaging?
Just because you are getting some jags does not mean you have a problem.
If it shows in your imaging and is insurmountable in processing, that's a problem.
But in my experiences, slightly wiggly-jiggly PHD graphs haven't shown me to be a major concern.

But then, it may be worth noting my delete key is worn smooth and is unreadable now.... ;^0
;^0 LOL!
--
SonnyE


(I suggest viewed in full screen)


Re: RA spikes towards west

Sonny Edmonds
 

How is your imaging?
Just because you are getting some jags does not mean you have a problem.
If it shows in your imaging and is insurmountable in processing, that's a problem.
But in my experiences, slightly wiggly-jiggly PHD graphs haven't shown me to be a major concern.

But then, it may be worth noting my delete key is worn smooth and is unreadable now.... ;^0
;^0 LOL!
--
SonnyE


(I suggest viewed in full screen)


Re: Poor Tracking GM8

 

Hi Chip,

Definitely a very brassy color. One thing I noticed is I have to turn the clutch knobs with excessive force to get the scope to have a stiff resistance to moving. Daniel said there might be too much grease on the clutch plates and that large nylon washer in the back. I'm going to take it apart and see. There's a good disassemble and cleaning video on YouTube. Thanks again for your help.

Best, John


Re: G11 with Gemini2 issues with Go To

Sonny Edmonds
 

I can't speak to the older, or first generation Gemini II units, mine is very newish, February this year.
But... have you tried a Factory Reset? Then enter your own Lon-Lat, time, and date, and pertinent starting info?



A factory reset takes a Gemini II back to it's infancy, and can dump any and all of the previous data that may have become corrupted.
I have experienced some bad behaviors on occasion, much like you describe, and a simple reset and fresh start fixed my woes.
So anytime things get wonky, like being 180¡ã off, I first try the Factory Reset, and renew my location data. (I use my Phone, and get accurate Long-Lat figures for my back yard.)

I like the simpler fixes first.

which I found fun and informative to watch.

Enjoy your new mount! I'm very happy with mine!
--
SonnyE


(I suggest viewed in full screen)


Re: G11 with Gemini2 issues with Go To

 

Hi James,

I'm one one the rarities in this group: I only have Gemini1 units so far.? Many of them....

So I cannot say explicitly that your Gemini-2 is exactly?the same as what I wrote.? You will have to see, or another owner with a G2 may tell us.??

I understand that there was only a PDF Gemini-1 manual, but not a PDF Gemini-2 manual.? I think the behavior and code are essentially the same between the two units, but the G-2 has more modern settings for new mounts.? The G-1 does not have the GM811 version listed, but is handled by using the Custom mount entries...and that is how I also handle McLennan metal gearbox mod that reverses the RA direction.? The G-2 would have the GM811 listed.?

(And....try the Cold Boot first to see if it fixes your pointing at the ground problem!)

All the best,
Michael



On Tue, Aug 4, 2020, 9:23 AM James B <jamiboothe@...> wrote:
Thank you Michael,

You mentioned the issues with Gemini 1. I have the Gemini 2 but with the first version of the control board. Will the above advice work for my version as well, and the attached manual is for the Gemini 1 and 2? I am going to try all of your suggestions today and see if I can get some consistency from the mount. Also, is there a factory reset? Maybe just starting as though the mount is brand new with all new info would be helpful, if it is reading cinfusing data?

Thanks for your indepth response,

James


Re: G11 with Gemini2 issues with Go To

 

Thank you Brendan,

When I had the mount connected to the web interface, the voltage was good. last night I was not able to connect through the ethernet (blaming on the new windows update), so my only information was from the hand set. When I installed the new battery the clip was very tight, but will check it again and use a volt meter at the battery. I have a couple of spare batteries and will check all of them today.

I am not sure how to check the ascom connection, but I will figure that out today, aswell.

Thanks for everything,

James


Re: G11 with Gemini2 issues with Go To

 

On Tue, Aug 4, 2020 at 02:51 AM, James B wrote:
Pointing in strange places I did not tell it to go.... but other times it points in the wrong direction.
Hi James - Brendan made some good suggestions for you

99% of the time this kind of issue is from incorrect Gemini settings for date/time/location/timezone.

So first is to make sure the info you are entering is correct - best to start with a Quickstart and walk through that wizard (that is the same as a Cold Start, followed by screen walkthrough) and make sure it's all entered correctly. If you are typing in your location, make sure you are using the correct values for your location relative to GMT -??is a good resource for this if you need it

Assuming you can get reasonable pointing from that point, then power cycle your gemini and check the values. If they are getting reset, then something is amiss, and we need to look more closely at that

hopefully it's just the settings


Brian



Re: G11 with Gemini2 issues with Go To

 

Thank you Michael,

You mentioned the issues with Gemini 1. I have the Gemini 2 but with the first version of the control board. Will the above advice work for my version as well, and the attached manual is for the Gemini 1 and 2? I am going to try all of your suggestions today and see if I can get some consistency from the mount. Also, is there a factory reset? Maybe just starting as though the mount is brand new with all new info would be helpful, if it is reading cinfusing data?

Thanks for your indepth response,

James


Re: Apology to the polar alignment scope

 

¿ªÔÆÌåÓý

I¡¯m glad to see they¡¯re still available. ?That¡¯s got to be a tough business, making a product that, once it¡¯s successfully installed, has a life of a quarter century, with a limited pool of potential customers. ?Everyone should upgrade, to encourage them to supply the next version when it comes due in ~10 years.

? -Les



On 1 Aug 2020, at 14:12, Chip Louie <chiplouie@...> wrote:

Les, Brian,

I used to eyeball it but that gave me sort of inconsistent results, stacks on stacks as it were. I was already guesstimating the position to position the reticle based on the constellation lines and positions and by adding yet another layer of estimation I think caused me to get too far from the correct position. It would work mostly but when it didn't I sort of struggled with GOTO accuracy.

My reticles were fine but old and I got tired of guessing and finding that I was a poor guesser. So I updated them and problem solved.?

Oh, the updated reticles are still available from Hutech Astro down in the OC> Look at the link: .? ? ?

--

Chip Louie - Chief Daydreamer Imagination Hardware


Re: Apology to the polar alignment scope

 

I bet this would be a NASA APOD if you would submit it.


Re: RA spikes towards west

 

Hi Magnus,

Given all that you have done, I doubt it is the mount drive.... but other ideas follow....

The camera optics are very sensitive to any mechanical looseness.??

When I've gotten glitches in my autoguider camera tracking, I often traced it to a slight wiggle in some one of the 1.25 inch tube or lockdown screws.? I doubt it really is the drive itself.? Last night I found a wiggle in a 90 degree?angle prism diagonal.??

My main deep sky cameras have 2 inch round nosepieces, but even those can loosen up.?

Tiny thumbscrews ...??
I often replace tiny thumbscrews with larger 6-32 or maybe 8-32 pointed end setscrews. ( I think I did that with some Oldham couplers too. I could not get the tiny Allen head wrench to really grab the tiny setscrew.? ?It pays to have a tap and die set, drill and number drill assortment around!)

Hope you solve your glitch trouble,

Michael



On Tue, Aug 4, 2020, 3:52 AM Magnus Larsson <magnus@...> wrote:
Hi!

I seem to have run into a problem where I think I'd need some smart
input. I've cleaned and relubed my G11, put everything together and
adjusted the RA worm as usual. Now I am also running a somewhat heavier
side-by-side setup. Carefully balanced in 3 directions. I have an OPW
(new design) with a high precision worm. Non-tucked motors. There is a
belville washer in the OPW.

What I get is spikes in the west direction, if I read it correctly. See
the last 3 guiding sessions in the attached PHD2 logfile, or the
attached screenshot of one of them. There are a few spikes in the other
direction as well.

Now, I'm surprised that these are in the west direction. My thinking is
that if there were something in the way, if the worm was not clean, or
if there was a problem with bearings or something else, these would
cause friction and spikes in the east, not the west, direction.

I've been playing with:

- adjusting worm against ring gear, so I can easily rotate it but not
more play than that

- adjusting the tightness of the clutches - thinking this was sticktion.
But it seems this far not to make a difference. Loosening or tightening
- no perceptible change.

- cables etc - I can not see anything that would cause problems, and
again, is this not in the wrong direction for that?

And I should mention that I was imaging M27, relatively high in the sky,
and it was no perceptible wind at all.


So: I think I have experimented with "the usual" suspects of bad guiding
behavior on the G11, and need some help thinking about what else this
could be. Should I dismantle it all again, clean and relube? Or what
could cause this kind of behavior? What am I missing here?



Magnus







Re: G11 with Gemini2 issues with Go To

 

Hi James,

Things to try... consider them beginners notes....

1.? ?Any time you change the date or time or latitude, longitude, etc: after you enter the new values you must power off the Gemini, then restart it.? ?It uses the values it reads from the SRAM with when it booted up.? It won't use the new values that you save in the SRAM, apparently because in the calculations it never goes back to read the new stored values.? [I'm guessing that, as nobody outside the Losmandy company has the source code to try and fix this.? Perhaps, if it used new values it might not know how to park...but again that would be in the (unknown to me) software design. ]?

2. The Gemini date and time entry may be tricky if you are entering them by hand.? The format for the date and time are given in the Gemini1 manual (I'll attach it for you)

UTC Date/Time:
The "UTC Date/Time" menu item is where you set Gemini's real time clock (RTC).
Upon executing "UTC Date/Time" the UTC date and time display freezes but the RTC
continues to keep time.
The display of date and time from left to right reads as follows: "yymm.dd hh:mm:ss"
(yy = year, mm = month, dd = day, hh = hour, mm = minutes, ss = seconds).

So would be for 2020, Feb 6, 06:15:25 am you'd enter. You take the 20 is the last 2 digits from 2020, the 02 is February, ...:
2002.06 06:15:25

For time after noon like 14:00 = 2pm enter like
2002.06 14:15:25

Link here works:
Click here to get the UTC data/time in?Gemini style.

Or full link:

________

3. Pointing into the ground is reported by many, and I see this problem from time to time on my Gemini1 units.? It is certainly a weird behavior.? ?The cause is most often a bad "Model" which is the "Tmodel" or telescope pointing model.? It seems to happen if you get a bad alignment point, and the Gemini can't get a good solution, and the result is one or more very large "correction" factors are in the calculated Model.??

You can see the Gemini unit Model values using the Gemini.net Advanced panel, pressing the Model button and downloading them from Gemini into Gemini.net, seeing them displayed. The reset button makes the displayed values zero, but the tiny curly arrow Upload to Gemini button does not work in the Model inset.? Instead use the big bottom buttons on the Advanced panel to Send to Gemini.? Then press Yes...that works to reset the Gemini unit model values to zero.??

Better:

??The easy solution is to park at CWD, then power off and do a Cold Boot.? Again, the bad Model fit is a software code issue as the code does not sense a ridiculously bad model value and tell the user "hey! that last entry gives a bad fit!...I'm rejecting it!"

The Gemini.net applet gives great access to the Gemini settings, and is worth it's weight in gold.? But that applet also does not review the Model data and warm you: "Your Model data has very high error values!? Your polar alignment (or cone angle or other error factors) are way off!? Recommend you Cold Boot and make a new model!".? ?I see the need for such a capability in the Gemini applet to save us from these nutty point at the ground behaviors.

4.? Be sure your Longitude is set correctly.? When the (older) Gemini(-1) boots up, mine says "latitude 122.2 W" but the handset entry will be -122.2.? so west is entered as a negative number.? Same if course for the latitude setting of mounts south of the equator.

5. Speaking of latitude and longitude. You see the dot "." in the hand entry.? That is not a decimal point.? It is a (USA usage) comma.? The entry after the dot is the Minutes...before the dot is Degrees.? The format is European style.??

[ Loving to digress as I do ...

I can only say the great Daniel Webster did this to us in the USA!? With the intent to make America distinct from England, he changed the spellings of many words (colour became color, etc) but he also changed the punctuation marks.? That's also why the period goes inside a quotation marks in the US but outside for UK writers.? She said she was "...hungry for power." vs "...hungry for power".? ]

Anyway, I hope these "beginners notes" help you out, after you verify the backup battery voltage is over 3 volts. ( I test that battery voltage while the battery is in the Gemini socket, because the terminal voltage under current load will drop vs the open circuit value when the battery is removed. Ideally the current should be so small it does not matter.? But if the circuit board has a tiny short, it will matter.)

[Looking at the code section at the back of the manual, I just discovered a possible reason my GoTos from Stellarium don't exactly center on my target.? Gemini has a High Precision Mode that gets the degrees, minutes, and seconds position. The low precision mode accepts degrees and minutes only.? Maybe the Gemini is set to Low Precision mode?? I'll have to try setting it in the High precision mode. I guess with the Model checker in mind too, it's time for me to try writing my own Gemini app.? ]

Best of luck, have fun,? stay well and safe,

Michael


On Tue, Aug 4, 2020, 4:11 AM Brendan Smith <brenatlilydale@...> wrote:
James

what does the ?

Are you sure your battery top "finger clip" is contacting the battery top with "force".? I have seen some a little "loose" poor contact that's dropping in/out Vbatt backup!? This happens as users tend to force up this "finger clip" when changing batteries....weakening its spring tension or bending it up slightly.? The newer "side clip" battery holders don't duffer from this.

Check this!? Also can you measure your battery with a multimeter? What? is it?? There have been rounds of bad or fake (poor capacity)? batteries!

Lastly are you sure something like Gemini ASCOM isn't "auto updating on connect"......incorrect date /time??? This has been seen before.

Get back on the above


--
Brendan


Re: G11 with Gemini2 issues with Go To

 

James

what does the ?

Are you sure your battery top "finger clip" is contacting the battery top with "force".? I have seen some a little "loose" poor contact that's dropping in/out Vbatt backup!? This happens as users tend to force up this "finger clip" when changing batteries....weakening its spring tension or bending it up slightly.? The newer "side clip" battery holders don't duffer from this.

Check this!? Also can you measure your battery with a multimeter? What? is it?? There have been rounds of bad or fake (poor capacity)? batteries!

Lastly are you sure something like Gemini ASCOM isn't "auto updating on connect"......incorrect date /time??? This has been seen before.

Get back on the above


--
Brendan


RA spikes towards west

 

Hi!

I seem to have run into a problem where I think I'd need some smart input. I've cleaned and relubed my G11, put everything together and adjusted the RA worm as usual. Now I am also running a somewhat heavier side-by-side setup. Carefully balanced in 3 directions. I have an OPW (new design) with a high precision worm. Non-tucked motors. There is a belville washer in the OPW.

What I get is spikes in the west direction, if I read it correctly. See the last 3 guiding sessions in the attached PHD2 logfile, or the attached screenshot of one of them. There are a few spikes in the other direction as well.

Now, I'm surprised that these are in the west direction. My thinking is that if there were something in the way, if the worm was not clean, or if there was a problem with bearings or something else, these would cause friction and spikes in the east, not the west, direction.

I've been playing with:

- adjusting worm against ring gear, so I can easily rotate it but not more play than that

- adjusting the tightness of the clutches - thinking this was sticktion. But it seems this far not to make a difference. Loosening or tightening - no perceptible change.

- cables etc - I can not see anything that would cause problems, and again, is this not in the wrong direction for that?

And I should mention that I was imaging M27, relatively high in the sky, and it was no perceptible wind at all.


So: I think I have experimented with "the usual" suspects of bad guiding behavior on the G11, and need some help thinking about what else this could be. Should I dismantle it all again, clean and relube? Or what could cause this kind of behavior? What am I missing here?



Magnus