Handcontroller Modification substitute parts?

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Jerome
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Handcontroller Modification substitute parts?

Post by Jerome » Fri Mar 28, 2014 2:59 pm

Hello.

I have an old Super Polaris mount which has been unused for several years, although last summer I cleaned, re-lubed, and verified it was still working. Adding a guide port has struck me as a great way to get some use out of it again.

It has a Vixen DMD-1 hand control, and it appears from testing the four direction switches that, from the "Handcontroller Modification Guidance" article, I will have to use either the GP1 or GP3 schematic plan for modifying it. I lean toward the GP3 approach for its input device independence, even though I'll probably mostly use a GPUSB.

I'm about to order parts, but have hit a small snag: Digi-Key no longer has the 2N2907 transistor in stock, and STMicroelectronics has it listed as obsolete. I've looked at a few other dealers (Mouser, Newark, JameCo, etc.) and they either don't have it or they have a generic or another manufacturer's version of it.

I'd prefer to get everything from one dealer, so is there another transistor offered by Digi-Key that will work as a good substitute? I have the suspicion that many would work, but I'm not good at deciphering the various specifications involved.

Thanks for any guidance.

dpanderson
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Re: Handcontroller Modification substitute parts?

Post by dpanderson » Sat Mar 29, 2014 9:25 am

Digikey part number PN2907-ND should do the trick.
Doug Anderson
Shoestring Astronomy
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Jerome
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Re: Handcontroller Modification substitute parts?

Post by Jerome » Sat Mar 29, 2014 12:51 pm

Thanks, Doug! :D

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