Re: 15v from usb-c pd

On Thu, Dec 7, 2023 at 05:33 AM, Will Taylor wrote:

I tried using a usb-c to barrel jack 15v adapter, and it seems to work with my gm811g.?
I have a small power bank that supports 15v at 3 amps (edited: I had written 3w.) It seems pretty convenient for my visual use, but I haven't heard anyone mention these before.
Any thoughts?

This is probably going to be a marginal setup. Get a larger higher capacity battery and a higher current regulated DC-DC step-up converter. While the Gemini 2 when slewing or tracking at a steady rate only pulls maybe 2A+ the peak draw will be higher even ramping up servo motor speed. You need to have some additional current capacity - 5A seems to be a good number for reliable operation IME.??

--

Chip Louie Chief Daydreamer Imagination Hardware?

? ?Astrospheric Weather Forecast - South Pasadena, CA?

Re: G11 DC Step-Up

#81808

Michael Herman is a huge friend of the Losmandy Community. Michael for many years now has been posting ways to improve Losmandy mounts and in particular Gemini 1 controllers and has generously offered to provide the same modifications and improvements almost for free. Michael is nuts if you ask me by I love him anyway.?

--

Chip Louie Chief Daydreamer Imagination Hardware?

? ?Astrospheric Weather Forecast - South Pasadena, CA?

Re: G11 DC Step-Up

#81807

On Wed, Dec 13, 2023 at 02:02 AM, Peter Eacmen wrote:

see alot of references to the "Michael Herman" power supply but cannot find where to purchase. Where did you get yours?

mherman346@...

Gemini-1 power booster~2.jpg

Re: G11 DC Step-Up

#81806

Hi Peter,

Michael is the “official repairer” in the US. He used to be quite active in these forums but I haven’t seen him in a while. The list of repairers can be found with his contact details.

Re: G11 DC Step-Up

#81805

I see alot of references to the "Michael Herman" power supply but cannot find where to purchase. Where did you get yours?

Re: Some pointing accuracy and polar alignment problems during setup

#81804

That makes a lot of sense. Thanks, David!

Jeff

Re: Warranty?

#81803

These user groups are full of people just like you, they don't work for Losmandy they share knowledge related to Losmandy product use and operation and troubleshooting. For issues like warranty, picing etc. contact Losmandy directly.??

--

Chip Louie Chief Daydreamer Imagination Hardware?

? ?Astrospheric Weather Forecast - South Pasadena, CA?

Re: Some pointing accuracy and polar alignment problems during setup

#81802

David is absolutely right - 15 degrees is 1 hour which very likely means an incorrect time zone offset setting, maybe still set to DST.

Show quoted text

On Fri, Dec 8, 2023 at 01:53 AM, jeff marston wrote:

I am not using my PC when I am getting pointing accuracy and polar alignment. The stars seem to be about 15 degrees off.?

Thanks for the response, Paul. I think I am going to do a bunch of dry runs in my living room with my Gemini 2 and hand controller.

Jeff

Re: Some pointing accuracy and polar alignment problems during setup

#81801

开云体育

Sounds like 1 hour of RA – so suspect daylight savings versus no daylight savings.

?

David

?

Show quoted text

From: [email protected] <[email protected]> On Behalf Of jeff marston
Sent: 08 December 2023 06:53
To: [email protected]
Subject: Re: [Losmandy_users_io] Some pointing accuracy and polar alignment problems during setup

?

I am not using my PC when I am getting pointing accuracy and polar alignment. The stars seem to be about 15 degrees off.?

Thanks for the response, Paul. I think I am going to do a bunch of dry runs in my living room with my Gemini 2 and hand controller.

Jeff

Re: Some pointing accuracy and polar alignment problems during setup

#81800

I am not using my PC when I am getting pointing accuracy and polar alignment. The stars seem to be about 15 degrees off.?

Thanks for the response, Paul. I think I am going to do a bunch of dry runs in my living room with my Gemini 2 and hand controller.

Jeff

Re: Some pointing accuracy and polar alignment problems during setup

#81799

Thanks for the video lead, Joe. I watched it and took some notes.

Jeff

Re: Some pointing accuracy and polar alignment problems during setup

#81798

I would guess about 15 degrees off, but it’s been about 18 months and I don’t recall the direction.

Re: 15v from usb-c pd

#81797

Well hell. ?What not trial it. If it works. ?Why not. You will be close to the minimum. ?But Ra ~200mA sidereal (varies amongst amounts) and slew can easily peak 1.2-1.5A per axes.

But that’s peak. ? Slowing slew rate may allow it to draw less current. ?
--
Brendan

Re: 15v from usb-c pd

#81796

Oops. Yes, that was a mistake. I should have written 3 amps not 3 watts.
Thanks.

Re: Hand controller won't boot

#81795

John,

Did you get it fixed??? If so, what was it??

Joe

Re: 15v from usb-c pd

#81794

开云体育

15 volts at 3 watts??? That is 15 volts at 3/15 amperes = 0.2 ampere, not enough amps to power the mount when it's slewing.? Or have I misunderstood?

Idea for next model of Gemini:? Volt and amp meters on the front panel.? That would make it much easier to troubleshoot a lot of problems people have.?

On 2023-12-07 08:33, Will Taylor wrote:

I tried using a usb-c to barrel jack 15v adapter, and it seems to work with my gm811g.?
I have a small power bank that supports 15v at 3w. It seems pretty convenient for my visual use, but I haven't heard anyone mention these before.
Any thoughts?

-- 
Michael A. Covington, Ph.D.
Consultant, Covington Innovations, Athens, Georgia, USA

15v from usb-c pd

#81793
Edited

I tried using a usb-c to barrel jack 15v adapter, and it seems to work with my gm811g.?
I have a small power bank that supports 15v at 3 amps (edited: I had written 3w.) It seems pretty convenient for my visual use, but I haven't heard anyone mention these before.
Any thoughts?

Re: Some pointing accuracy and polar alignment problems during setup

#81792

Hi Jeff,

Most likely some Gemini setting is entered incorrectly. What version of Gemini are you using, and what level of firmware? Do you connect your PC to the mount before doing that first Goto? And is the star within a 5 degree field of a finder, or even further off??

The most common errors are with:

1. mount type set in Gemini
2. date and/or time
3. timezone
4. geo location
5. large polar misalignment

Regards,

? ? -Paul

Show quoted text

On Wed, Dec 6, 2023 at 10:57 PM, jeff marston wrote:

I am not sure whether it’s a daylight savings time issue or what. When I put in all the data including gps location, local time, and time zone, my mount doesn’t go anywhere near the calibration stars it’s supposed to go
to. I have tried changing to a fresh battery in the little back box, but that didn’t seem to change anything. If I do big slews to where the stars are supposed to be I can eventually get things working, but it takes a lot of time to get there. The setup at my dark site is complicated enough without having to trouble shoot my mount every time. My Celestron mounts will ask for standard time or daylight savings time specifically but my Losmandy doesn’t. I?rarely have those issues with my Celestron mounts so I have been using them instead, but it would sure be nice if I could figure out why my Losmandy has become difficult to set up. Sometimes I just need my big G11T
for my bigger SCT’s when I am imaging.

Re: Some pointing accuracy and polar alignment problems during setup

#81791

Jeff,

I know daylight savings time can be a pain, been there done that too.? Anyway, check this video out, at least the first half about 8 minutes of it.? It goes through set up info.? There's a website that gives you accurate time zone offset info.

I hope this solves your problem.

Joe

Re: Some pointing accuracy and polar alignment problems during setup

#81790

The crucial question:? How far is it off, and in what direction?