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Who else has a Takahashi EM-2S Mount?

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#1 buckeye_hunter

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Posted 21 June 2009 - 01:24 PM

Could I send you my hand controller to see if it works on your mount?

Thanks in advance...

Bob

#2 buckeye_hunter

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Posted 25 June 2009 - 09:15 AM

No one. Really?

#3 Chris Curran

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Posted 25 June 2009 - 09:37 AM

Why not send it to TNR instead?

#4 buckeye_hunter

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Posted 25 June 2009 - 01:31 PM

I spoke with Art at TNR. He was very helpful and this is not in any way meant to disparage him or TNR, but when he suggested sending it down but could not tell me whether parts were available or what the cost would be, I felt that was a bit too open-ended. I don't want to end up with a huge repair bill on a 20 year old mount that could go toward something else.

I know that TNR can get me a new stepper motor ($195), so if I can be assured the hand control works, I can buy the new motor.

I know that TNR cannot get me a new hand controller.

Clear Skies!

Bob

#5 zawijava

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Posted 26 June 2009 - 01:40 PM

I spoke with Art at TNR. He was very helpful and this is not in any way meant to disparage him or TNR, but when he suggested sending it down but could not tell me whether parts were available or what the cost would be, I felt that was a bit too open-ended. I don't want to end up with a huge repair bill on a 20 year old mount that could go toward something else.

I know that TNR can get me a new stepper motor ($195), so if I can be assured the hand control works, I can buy the new motor.

I know that TNR cannot get me a new hand controller.

Clear Skies!

Bob


Bob,

I used to have a Tak EM-1 mount, similar to yours...a bit older. It is quite a simple mount. I would venture a guess that any knowledgeable tech at Radio Shack could put a tester on the output leads of the hand control and verify if it's putting out power. Or even better, the mount is so light you could take the entire head in. With the motor cover(s) removed and hand control attached(with power) the tech could test it quite easily. BTW, is this a RA axis drive only or Dec axis as well? If dual axis drive, are they both not working? It's not likely that you'd have two drive motors fail at the same time.

Tim

#6 GJJim

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Posted 27 June 2009 - 07:59 AM

Please describe the hand controller you have. I owned a Tak EM-1 (RA drive only) and it had a simple controller with only two buttons - 2X and stop. There are no active electronics in the thing, just two switches and the interconnect cable to the mount. All of the electronic components are inside the mount itself, and it would run at the siderial rate even if the hand controller is disconnected.

#7 buckeye_hunter

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Posted 27 June 2009 - 11:52 AM

Tim,

This is a RA drive only. I am not so trusting of techs at Radio Shack. I do know that the stepper motor pulses when I connect to power source, so I know that the hand controller is receiving and sending power.

Jim,

The hand controller for the EM-2S has a power switch; a direction switch (hemisphere); a pause button; and a speed-up button. Sounds quite the opposite of the EM-1.

I have not been able to locate a schematic for the electronics. I know that the hand controller contains a crystal oscillator to send pulses to the stepper motor at a precise frequency to attain siderail rate. My brother used an oscilloscope and could not get a signal from the oscillator, so our best guess at this point is that the crystal is faulty. It is an odd frequency (821.444KHz) and so far I haven't been able to source a replacement to try. If I could confirm that the hand controller is shot, we could start building a new programmable stepper motor controller.

I was sent this link by someone on AstroMart:

http://www.telescope...boxdoerfer.html

Very nice, but VERY PRICEY! Over $500 USD.

I would still love to find another EM-2S to test my hand contoller!!!

Thanks and Clear Skies!!!

Bob

#8 tim53

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Posted 27 June 2009 - 05:32 PM

What does your hand controller look like?

My old EM-500 mount has two toggle switches and 2 dec and 2 RA buttons on it IIRC. None of my current Tak mounts (the ~1993 EM-500 non-goto, 2000 NJP Temma PC, EM-10 Temma 2 Jr) have powered hand boxes - they're just switches that plug into the mount.

Have you ever seen this Tak history web page?: Tak mount history

There are a couple of pics of EM-2 mounts on it, but they don't show the hand controller. But one of the other mounts pictured might have the same hand controller.

-Tim.

#9 buckeye_hunter

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Posted 27 June 2009 - 11:45 PM

Scroll down in the manual

http://www.takahashi...M_2S Manual.pdf

Page 5 shows the hand controller.

Bob






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