GPUSB DEC- Line Not Releasing

[rzep]

Well.. I think I fried it. I'm in process of making a 12 VDC relay box interface based on the GP-1 diagram. I didn't use the Digikey relays, but I did use 12 VDC reed relays from Radio-Shack. The coil ohmage was about the same (1050) so I thought that would be OK.

I pinned my own 6 pin cable which I did check with an ohm-meter so I was definitely 1 - 1, 2 - 2, etc, with no cross connects or opens.

I ran GPUSB check. When I first powered everything up, all the relays where de-energized. I then went one by one (RA+, RA-, Dec+, Dec-) and all the relays worked beautifully!! Did this several times. Now during one test on the DEC- side, I got a phone call when it was energized and left it that way for about 1/2 hour. When I tried to turn it off, it wouldn't de-energize.

I did a diode check with my multimeter, RA+, RA- and DEC+ vary between open and .57 VDC depending on the command. On the Dec- line I get .67 VDC no matter what the command is. Tried resetting the GPUSB with no change. I think that line is toasted

Hopefully, you can do a repair??

Thanx.

[dpanderson]

Yes, we can repair the GPUSB. Send an email to doug@ShoestringAstronomy.com and I will reply with the details.