Visioneer One-Touch 7600 USB

[banzaikai]

Howdy.

I'm currently repairing a Visioneer 7600 USB scanner for a neighbor, and he doesn't have the AC to DC adaptor for it (he was given an AC-AC adaptor by mistake, and that's why I'm repairing it :D ). I've searched all over, downloaded whatever PDF that Visioneer had on their site, and even tried to zoom in on images over at NewEgg, but nothing's coming up.

If one of you kind folks out there happens to have one, could you please look at the voltage/current listed on the adaptor and post it here? I'm guessing it's about 12V@1-1.5A. Schematics would be even better, but I've got the insides mapped out well enough.

banzai "...done dirt cheap!" kai

[missingxtension]

Well to tell u the thruth i dont know for sure since i too lost my AC adapter a while back, but i can report that the one im using seems to be working right and it might even be the original i dont know but the specś

Brand: liteon
model: PB-1090-1L1
Input: 120V ac 60hz 0.3a
Out: 12v DC 700mA
Caution: Indoor use only

on the adapter end that goes to the scanner
the outside is negative -----(o----- and the inside is possitive
hope this helps

[banzaikai]

Kinda late on this one...

While popping the thing open (and repairing), I was able to throw my variable power supply on it, and it seemed to run best at 12V (polarity was easily found). So, I just picked up a 12V/1.25A from Jameco (Mouser?), and, oddly enough, the software from another neighbor to test it out. The scanner is now seen by the system, but it looks like I'll have to check the scan lamp for damage, as it's not lighting up...

Oh, well.

banzai "better late than never" kai

[missingxtension]

mines does that every once in a while
you might be able to find some interesting info on th is product
by checking out the sane linux driver page if im not mistaken i found some
diagrams that might help it had all that information and circuitry if youre
trying to fix it

[banzaikai]

Awesome! Thanks, MX!

I was about to write to Visioneer's tech support, but I'll look at Sane first.

Here's my current status (for those interested or mind-boggingly bored):

I bypassed the logic board and wired the cold cathode up to my variable power supply. The light clicked on at ~8VDC, and really looked good around 11-12V. So, that meant the high voltage section managed to survive, and the problem was back in the logic (main) pcb. I had fixed all the blown caps (only two that I saw, both 100uF/16V), and the one inrush resistor (50 ohm smt). I traced the 12V for the CC lamp back to pins 15/16 on the ribbon header, but it's reading only 0.6V.

BTW, I actually ran this thing through a test scan, and the only thing not working is the lamp control turn-on - it scanned a really dark, streak-ridden ... something. And without anything else going "bang".

Now, surface mount isn't my strong point, especially without schematics, as this is a multi-layered pcb, and it's hard as hell tracing paths on it. So, right now, I'm trying to find/test everything up to the header to see what's not letting the lamp click on.

Another odd thing: when I put my logic probe on the ground of the first 7805 VReg, it shows as pulsing (since the LP I use has no power light, I test by probing a ground to see if the logic low light beeps on). This tells me I may have a few more caps to replace (filters). Still, a schematic is really what I need to figure this thing out.

banzai "fluxmaster" kai

[missingxtension]

ohh yeah youl find what youre looking for there!!
although i dont know exactly what you said i have and idea and you just said
the bulb worked!! lol
let me see if i can find u a link to exactly what i saw
also good luck trying to get sane to work with this i wasnt able to

[banzaikai]

Well, nothing's there that helps me out.

I need schematics or chip pinouts (for the EICI series) to figure out the traces. For the time being, I'm shelving the scanner (got a PET 8032 that's acting funny - and I've got schematics).

Yeah, I know that a new scanner would cost less than fixing this one, but it's the principle of the thing.

banzai "tracing paper" kai