Vixen DMD-3 controller with GPUSB questions

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kiwiguy
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Vixen DMD-3 controller with GPUSB questions

Post by kiwiguy » Mon Sep 17, 2018 2:01 pm

Hi,

I am working on adding the cable to Vixen DMD-3 controller to connect to a GPUSB.
I'm a bit confused about a couple of things (haven't done anything yet)

1. I bought a GPUSB-AH (Active High) based on previous reading about the DD-1 but not sure if that is correct for the DMD-3.

2. If I'm only using the GPUSB do I need relays, or can I just wire the RJ12 cable directly to the push button pins?

3. Which connections to wire to? The picture in the documentation (eq_mod.pdf) is similar but not exactly the same.
http://www.store.shoestringastronomy.com/eq_mod.pdf

Attached are photos of the controller and board.

Any 'guidance' would be appreciated.

Thanks,
David
IMG_5974 (1).jpg
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IMG_5975 (1).jpg
IMG_5975 (1).jpg (43.32 KiB) Viewed 61 times

dpanderson
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Re: Vixen DMD-3 controller with GPUSB questions

Post by dpanderson » Tue Sep 18, 2018 6:35 pm

David,

This doesn't look like it will be as simple as the EQ handcontroller modification. It is probably more like the GP1 or GP2 circuits shown in:
http://store.shoestringastronomy.com/do ... idance.pdf

Since you have purchased the GPUSB-AH, you can use the referenced above, but you would need to swap the Ground and Positive Supply connections.
Doug Anderson
Shoestring Astronomy
http://www.ShoestringAstronomy.com

kiwiguy
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Re: Vixen DMD-3 controller with GPUSB questions

Post by kiwiguy » Tue Sep 18, 2018 11:43 pm

Thanks for the quick reply!

Therefore, should I just follow the instructions in this article?
https://www.cloudynights.com/articles/c ... port-r2591

dpanderson
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Re: Vixen DMD-3 controller with GPUSB questions

Post by dpanderson » Wed Sep 19, 2018 1:04 pm

Very nice discovery! That looks exactly like what I was thinking. Since you have a GPUSB-AH, the only difference would be reversing the (+) and (-) connections shown in Figure 6.
Doug Anderson
Shoestring Astronomy
http://www.ShoestringAstronomy.com

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