G11 Gemini controller switch problem

[h0ughy]

I had a horrible time last night trying to get first light in the observatory. It was clear last night, though not great, but I was eaten alive by mosquitoes setting up then the worst happened, the G11 would not fire up. When I bought the G11 second hand I was told the switch was a little dicky, and in practice it was when I used it for the last time during the total lunar eclipse in 2007. The rest of the time it has sat packed nicely in the shed waiting for the Doghouse Observatory to be built. I have power, I checked the source and even used another to validate that there was go go juice there. But the darn thing would not turn on. Frustratingly I thought that the cr2032 battery was dead, and remembering that I had a new 1.05 version chip to replace the 1.02 I then though that I would replace the EPROM – which I did. Then came the Cr2032 battery. Now I buy heaps of these things – do you think I could find one in the house or shed – no way. Arrrg – must get one today, but the thing that still is on my mind – the switch. I think it is faulty and not making contact. Can these things be replaced, or is it wise to source out a new board?

[Omaroo]

David - I have exactly the same problem on my Model 492 Digital Drive - the dicky power switch. I have no clue as to why Scott Losmandy would use such awful quality switches in units that are otherwise very well made. It makes no sense to me.

Given that, it's a two-minute job with either solder wick or sucker to remove it and replace it with an equivalent from Jaycar - a really simple task. Until then though - you might try to exercise the switch by removing power and rapidly switching on/off for 20 or 30 cycles. this may polish and internal surfaces and regain partial contact.

It's not worth replacing the board by any stretch of the imagination.

[Barrykgerdes]

Hi David
Those switches are pretty cheap and nasty and have been known to cause trouble. I would not think twice about replacing it with an identical one from jaycar or the like. But that was my field many years ago.

However before you remove it from the board check its action with an ohm meter to make sure that is the only problem.

Barry

[h0ughy]

thanks guys, i wont be removing anything as my skills don't allow me to do that (i have none). Probably have to send it off somewhere to get fixed. I cant use the system at all until this is fixed - and there are clear night ahead - typical

[Omaroo]

How's Al with a soldering iron? :)

[RB]

Pity we don't live closer Dave, I could've had a look.
How soon do you need it ?
ASAP I assume.
I would've made a trip up to help you out but as you know atm I'm flat out with work.
If I get a break in the meantime I'll give you a ring.

[JohnG]

Hi Dave

Sounds a lot like the switch to me as well, the new model Gemini has a revised switch after numerous complaints to Losmandy. I doubt that it would be the CR2032 battery, it would usually show on the hand controller as CMOS reset.

I believe Bintel in Sydney has a test bench for the Gemini or I would imagine that ATS would have one as well.

Cheers

[h0ughy]

yes i would have thought that it would have powered up with lost memory postiion but i didnt get it turned on at all:sadeyes:

[h0ughy]

waiting for a call.....:lol:

[wasyoungonce]

You can get a very similar switch from DSE (http://www.dse.com.au/cgi-bin/dse.storefront/4b709f2e021121702741c0a87e010679/Product/View/P7602).

A TV repair place will replace it no problems...it's a small job...should only be a few bucks at most.

Just show up with the cct board & switch.

[h0ughy]

thanks

[Peter Ward]

That particular switch was phased out many years ago as, yes, it does burn out (the higher current draw of the servo's was not anticipated)

Newer revision PCB's use a totally different (high current) switch.

You can either replace it yourself, or send it to a servicing Losmandy dealer
( no prizes) who will replace it for $37.00 (inc return post)

[h0ughy]

if it was replaced with another switch - which one would it be ;). how quick for the turn around?

[[1ponders]]

Yep the switch it is. I had mine replaced with a toggle switch at a local TV repair guy for the staggering cost of $10 including the switch. Haven't hada prob since. This was on the DD of the G11, must the the G8 one day and the Gemini at the observatory as it is a pita at time.

[h0ughy]

ok ,
i listened to my doctor - Dr RB and followed his prescription and it worked - but i also bought a spare switch, i used the spray and that worked a treat - i managed to fire up the beastie tonight, i was able to get the gps to work, but for the life of me i feel so green - i have no idea how to run the mount, to slew, really to do anything LOL. three years i have had this and the last time was august 2007. i need some lessons - and really need to read the manual.........

[[1ponders]]

Come on up for a holiday Dave. I'll show you how to work it. Then you can leave it here ready for astrofest. Plenty of room :D

[h0ughy]

its bolted down paul ;)

[alan meehan]

HEY dave glad the switch is working just needed some wearing in ,iam glad cause iam hopless with a soldering iron.

[[1ponders]]

Thats alright Dave I have a spare tripod
:D

[RB]

:lol:

So the Jaycar spray did the trick !
Glad I could help Dave.

:)

[h0ughy]

I still will get the switch changed at some time, i am sure that at some critical point it will fail

[h0ughy]

Peter,

I will send it the next full moon;), the switch buggered up again tonight but eventually turned on - then so did the weather. Can you post what the new switch will look like - is it bigger? Also Can you PM me the address to send it:thanx:

[h0ughy]

I'll send it tomorrow - given the weeks forecast will be rain and showers every day - it doesnt look promising

[thomqos]

Reviving a very old thread; Tried to power up my G11S Model 492 drive last night after 10 months of no use... Nothing! Absolutely nothing!!! So I had to play the dobsonian game for the night and push the mount around. :(

I got this mount in 2013-14 and the switch has always been a bit dicky, exactly as others have described below. But last night it didn't want to play the game, I was suspecting a more serious electronic problem actually.

So I found this thread, pulled the circuit board out of it's box and toggled the switch back and forth furiously about 50 times... Then it finally turned on! Oh how frustrating.!!

So I'm off to Jaycar to see if I can source a replacement switch....

[multiweb]

Might want to talk to Brendan (wasyoungonce)

[wasyoungonce]

Russell i's the switch as usual. The contacts just go bad, quite normal in DC switches.


OEM is C&K Switch 1101M2S3CBE2. That's a silver plated contact....I do believe there are gold plated contact versions available (which should last longer) but I haven't seen any of these.



Best just replace with the OEM:
RS Components: 161-7640 $6.41 or E14: 1437698 $9.44 + $post There are cheaper switches that would fit....but...IMHO...use to correct one. If you solder it in....Keep heat on the pins to a minimum as heat allows contaminates to form on the contacts.



I have one new in my spares. Same switch was used in some earlier Gemini 1's. If you want me to replace it I can as I'm keen to get a copy of the EEPROM firmware. ;)I have all parts for the 492 system except the firmware.

[thomqos]

Thanks for the part number Brendan! Jaycar had nothing remotely like it. I might buy a few...
I'm handy with a soldering iron, so I'll be right to replace it myself, but thanks for the offer.
You're welcome to copy the firmware if we ever bump into each other with an EEPROM firmware reader, lol!

[thomqos]

I ordered 3 of the OEM switches from Radio Spares & they turned up today... But I have 'fixed' the original switch for now... Anyway, I have the spares now to deal with the inevitable when it happens!