Roy J. Gromlich wrote:

> I am asking this question here because I am getting 
> absolutely nowhere with Microtek.

You expected otherwise?

> I have had a Scanmaker 4900 for about two years - 
> was working great.  In the process of moving it to 
> another computer it was accidentally powered from 
> a 12 volt wall wart instead of the proper 12 volt 
> switching supply.  The switcher is apparently 
> regulated, while the wall wart wasn't, and probably 
> went above 12 volts.
> 
> Since then, even though connected to its proper power
> supply,  the scanner has not produced its usual beautiful
> scans - they are washed out and get more so the longer the
> unit is turned ON, until after 2 minutes there is nothing. 
> Obviously something was zapped by the overvoltage.  

Check for chips that are overheated. Try
cooling them individually with freeze spray to see
if it's a chip or a tantalum cap (the cap is more likely).

> Now Microtek wants a Lot of money ($80 to $100) to
> fix it - I can buy a new one for that amount.  I asked 
> them for schematics so I could take a crack at it, but 
> no go - I was told it was too difficult to take the case
> apart without breaking it.  Actually, I popped the case
> off in about 3 minutes - nothing broken. I informed them
> of that fact and was advised to call their professional
> consultants - at $30 per call.
> 
> So here is the question - does anyone out there, by some 
> strange chance, have schematics for a Microtek 4900
> scanner? 

If they do, they'd be forgeries. This kind of information
is NEVER released by a manufacturer. As far as they are
concerned these devices are 'not repairable'.
The $80 repair charge is for a 'new' logic board or
whatever since as you noted a complete new scanner costs
as much.

> Or even a close model 4800, 4850 ?  I know
> the chance of this is very small, but I figure it can't
> hurt to ask.

You would have more luck asking for winning lottery
numbers.

R


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