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Anyone using JMI or Vixen Train and Track?

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#1 Eddgie

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Posted 08 November 2013 - 07:02 PM

After my long post about the Polaris, I just found a mount that has some promise.

The only reason that I keep the Polaris is the simple tracking setup, and the ability to switch easily to Alt/Az.

But now I see the Vixen StarGuy with Train and Track motors (JMI has a version).

Anyone running this?

If so, questions..

How long do the batteries last?

Are there high speed slews or just the Train/Track modes?

Also, once it is tracking, I have to assume that it will only track that one object and that if you move the scope, you have to re-train???

That might not be a problem for me because I only intend to use the tracking for planets or white light solar, but it would be nice that if once the drive was trained, if I slewed electronically (see "High Speed Slew above) that the logic circuit re-calculated, but my guess is that it is a simple vector logic at best, and at worst, you are just tuning each motor individually and that there is no arc processing at all, and just a simple vector.

And that brings me to the final question which is is this basically how it works and does it have any logic at all, or does it simply run the motors at the rate required to follow a straight line.

Thanks to anyone that can help!

#2 beatlejuice

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Posted 08 November 2013 - 08:43 PM

Ed, take at look at this short thread and then ask for any further clarifictaion TNT

Be advised that these are not true tracking motors. It is definitely NOT plug and play. You have to practice with the controls and then perhaps you can get 5+ min of reasonable tracking before more adjustments need to be made.

The batteries seem to last a reasonable amount of time, haven't changed them yet but also haven't used them all that much over the past year.

There are no clutches involved so you can move around the sky by hand no matter whether the motors are running or not. It is definitely nice to not have to reach for slo-mo cables, but the tracking part is really kind of tricky.

Eric

#3 Eddgie

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Posted 08 November 2013 - 09:04 PM

Exactly the kind of information I was looking for.

So basically it sounds like you are just trimming the motor speeds to make the motor move so that the mount is moving in a strait vector, and little more than that.

Well, I was hoping that it used some kind of internal logic to actually allow it to "Learn" the arc of the target, but it now seems more likely that it is just two motors running at constant speed that you are tweaking.

In other words, I loose the counterweight from the Polaris but I add 3 cables and 7 batteries, a second motor, and add another box (battery box, and I still don't really get "Tracking."

I want to find a simpler way than the Polaris, but once again, I keep coming back to a simple GEM as being about the minimum that works for me.

Oh well, it looked so promising.

I guess I thought it was more than two variable speed motors and some potentiometers.

Again, thanks for the info and the links.

I searced for "Track and Train" and did not know to searchon "TNT".

#4 beatlejuice

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Posted 08 November 2013 - 09:36 PM

Well, I was hoping that it used some kind of internal logic to actually allow it to "Learn" the arc of the target, but it now seems more likely that it is just two motors running at constant speed that you are tweaking.



Well the motor speeds are variable and do tend to learn the arc of the tangent, its just that the process is very finicky and the end result, which I have not taken enough time to become fully proficient at, is at most a few minutes at a time after which the process would have to be repeated.
Yes, the EQ mount with RA drive is most likely your best solution without getting into megabuck alt-az setups.

Eric






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