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'[EE]: looking for schematics or other info on Micr'
2005\05\11@163840 by J. Gromlich

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

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.  
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?  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.

RJG

2005\05\11@223228 by Robert Rolf

picon face
Roy J. Gromlich wrote:

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

You expected otherwise?

{Quote hidden}

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).

{Quote hidden}

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


2005\05\12@084706 by J. Gromlich

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face

I suppose I didn't expect much help from them, but their attitude has
been go away & don't bother us.  Quite a shame, really, because they
make a great product.  However, I could never recommend them to
anyone after this.

There are no obviously overheated chips, nor caps for that matter.
But then tantalums either show no changes, or else crack open if they
get hot enough.  I had planned to go over the controller card looking
for the changing voltage, and then following it back to the source.
However, that would be a whole lot easier with a schematic to follow.

As for releasing schematics, I have never really understood the issue.
In the case of a scanner, most of the complexity and cost is likely to
be in the optical hardware, and ultimately the firmware controlling the
hardware. If I wanted to clone the scanner it would take me longer,
and cost a lot more, to duplicate the optical hardware & the firmware
than to simply copy the circuit board.

I have designed many electronic products, and in all cases the hardware
(configuration & packaging) were far more important than exactly
which chips were on the PCB.  And, in many cases, even if you make an
exact copy of one of my PCBs, you would still have to have a way to
duplicate/copy the embedded code to make it work.  Not that that can't
be done, of course.

Let this be a warning to designers - don't rely on an external plug-in
regulated supply alone to protect your hardware. Especially when using
a standard plug & jack pair as would be found on any unregulated wall
wart. Had this scanner had a voltage regulator on the main board, or a
different type of power plug to the regulated supply, it would not have
mattered if the wrong wall-wart was plugged into it. The regulator might
have gotten hot and gone into thermal shut-down, or maybe popped a fuse.

RJG

> {Original Message removed}

2005\05\12@102155 by Herbert Graf

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face
On Thu, 2005-05-12 at 08:47 -0400, Roy J. Gromlich wrote:
> I suppose I didn't expect much help from them, but their attitude has
> been go away & don't bother us.  Quite a shame, really, because they
> make a great product.  However, I could never recommend them to
> anyone after this.

Well then you won't be recommending ANY company that sells electronics
these days, because pretty much every single one of them will behave in
the exact same way.

Nobody "repairs" electronics anymore, at the lowest levels whole boards
are replaced, with many items replacing the item is the way to go. This
is a fact of life.

> As for releasing schematics, I have never really understood the issue.
> In the case of a scanner, most of the complexity and cost is likely to
> be in the optical hardware, and ultimately the firmware controlling the
> hardware. If I wanted to clone the scanner it would take me longer,
> and cost a lot more, to duplicate the optical hardware & the firmware
> than to simply copy the circuit board.

Releasing the schematic MAY give away some "secret" a competitor might
use. No matter HOW remote this possibility is, this is what causes
companies to just say no.

And it's not just schematics. Getting specs out of manufacturers for
writing your own OS drivers has been EXTREMELY difficult. It's only
lately that some manufacturers are either opening up or developing
drivers of OSs other then wincrap.

> Let this be a warning to designers - don't rely on an external plug-in
> regulated supply alone to protect your hardware. Especially when using
> a standard plug & jack pair as would be found on any unregulated wall
> wart. Had this scanner had a voltage regulator on the main board, or a
> different type of power plug to the regulated supply, it would not have
> mattered if the wrong wall-wart was plugged into it. The regulator might
> have gotten hot and gone into thermal shut-down, or maybe popped a fuse.

Obviously you have never been a manufacturer in the market of computer
peripherals. Computer peripheral margins for most areas are EXTREMELY
thin (there are of course exceptions). Yes, the extra $0.50 for a
regulator and associated components is often enough to cause a maker to
decide not to manufacture a product.

Also, you forget, that plugging in the wrong adaptor is NOT something
covered by warranty, and since it's something you did to the product
it's not something you can blame the product for. The average person
will not even enquire as to how much it would cost to fix it (since they
know it would be more then a new item) and will simply go out and buy
the latest and greatest, which rewards the manufacturer for not putting
in the regulator to begin with.

TTYL

-----------------------------
Herbert's PIC Stuff:
http://repatch.dyndns.org:8383/pic_stuff/

2005\05\12@104922 by Gerhard Fiedler

picon face
Herbert Graf wrote:

>> I suppose I didn't expect much help from them, but their attitude has
>> been go away & don't bother us.  Quite a shame, really, because they
>> make a great product.  However, I could never recommend them to anyone
>> after this.
>
> Well then you won't be recommending ANY company that sells electronics
> these days, because pretty much every single one of them will behave in
> the exact same way.

Maybe not... I've had no problems getting a complete service manual for my
ViewSonic P815 monitor. (Cost me a bundle at the time, but then this is not
a $80 scanner.) You could argue that there is a lot more IP in those
schematics than there is in the schematics of a $80 scanner, as there is a
lot more non-trivial electronics.

My impression is that there are differences between companies. Of course
it's still the question how high these rank on your priority list when you
buy an equipment (given that you know about them then).

Gerhard

2005\05\12@110625 by Herbert Graf

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face
On Thu, 2005-05-12 at 11:49 -0300, Gerhard Fiedler wrote:
> Herbert Graf wrote:
>
> >> I suppose I didn't expect much help from them, but their attitude has
> >> been go away & don't bother us.  Quite a shame, really, because they
> >> make a great product.  However, I could never recommend them to anyone
> >> after this.
> >
> > Well then you won't be recommending ANY company that sells electronics
> > these days, because pretty much every single one of them will behave in
> > the exact same way.
>
> Maybe not... I've had no problems getting a complete service manual for my
> ViewSonic P815 monitor. (Cost me a bundle at the time, but then this is not
> a $80 scanner.)

That's exactly the point. A monitor, especially an expensive monitor,
does still have an expectation of being "repairable", hence the fact
that a service manual is available.

But you ARE talking about an $80 scanner.

> You could argue that there is a lot more IP in those
> schematics than there is in the schematics of a $80 scanner, as there is a
> lot more non-trivial electronics.

Remember, it doesn't MATTER how much "IP" there is in the schematics,
it's the fact that there MIGHT be something "good" in those schematics
that a competitor might be able to use that scares companies.

> My impression is that there are differences between companies. Of course
> it's still the question how high these rank on your priority list when you
> buy an equipment (given that you know about them then).

Of course there are differences between companies, my point is the
majority of companies making lower cost computer peripherals probably
won't even answer your email requesting a schematic. TTYL


-----------------------------
Herbert's PIC Stuff:
http://repatch.dyndns.org:8383/pic_stuff/

2005\05\12@114029 by olin_piclist

face picon face
Roy J. Gromlich wrote:
> I suppose I didn't expect much help from them, but their attitude has
> been go away & don't bother us.

I think their attitude is completely reasonable, assuming the product was
out of warranty (which I gather from your description it is).  They have met
all their obligations.  Supporting people who want to open the scanner and
monkey with it was never part of the deal.

Scanners are high volume products where every penny matters.  It is quite
reasonable to design such a product to be unserviceable in return for lower
cost per unit.  Many products are designed that way today.  The labor to
diagnose and then correct a problem exceeds the cost of building a new one.
Therefore there is no need to create the documentation and train techs,
again allowing the product to be cheaper.  You said your price for a whole
new scanner is about $80.  As you pointed out, the most expensive part of
producing a new scanner is probably the optical setup and associated test
and calibration time.  The cost of a new fully assembled circuit board is
probably around $10.

> There are no obviously overheated chips, nor caps for that matter.
> But then tantalums either show no changes, or else crack open if they
> get hot enough.  I had planned to go over the controller card looking
> for the changing voltage, and then following it back to the source.
> However, that would be a whole lot easier with a schematic to follow.

So how long have you spent on this, including time to complain about it
here?  Even if you had a schematic, how long would it take to diagnose the
problem, find the part or parts that got fried, get replacement parts,
remove the old, install the new, and hope that nothing else more subtle is
still wrong?  $80 for a new scanner sounds like a better deal.

> As for releasing schematics, I have never really understood the issue.
> In the case of a scanner, most of the complexity and cost is likely to
> be in the optical hardware, and ultimately the firmware controlling the
> hardware. If I wanted to clone the scanner it would take me longer,
> and cost a lot more, to duplicate the optical hardware & the firmware
> than to simply copy the circuit board.

But there is absolutely no upside in releasing the schematic, and a bunch of
costs, not the least of which is having to answer questions from people who
thought the schematic gave them license to screw around and ended up
breaking something.  There just is no win in it.  Look at the amount of
their time on the phone you already wasted.  Imagine how much more of that
would happen if people had the schematic in their hands.

> Let this be a warning to designers - don't rely on an external plug-in
> regulated supply alone to protect your hardware. Especially when using
> a standard plug & jack pair as would be found on any unregulated wall
> wart. Had this scanner had a voltage regulator on the main board, or a
> different type of power plug to the regulated supply, it would not have
> mattered if the wrong wall-wart was plugged into it.

In this one case, a more expensive design might have saved it.  However,
think about how many scanner would then be burdended with the more expensive
design without it ever providing an advantage.  Most people are going to
plug the thing in with the wall wart that came with it, and probably leave
it that way until they retire the unit well after its warranty expires.
Good design is about chosing the right tradeoffs, which is never "best" from
all angles.  Protecting against the 1 in 10,000 case of someone plugging in
the wrong wall wart isn't worth it.  It's better to make it a dollar cheaper
and have slightly more sales.

Also, you know you screwed up here, and it's not fair to blame the
manufacturer.  The company has delivered everything it promised for the
relatively little money you paid.  $80 for a complex piece of precision
equipment like a scanner is really amazing then you think about it.  Imagine
how much it would have to cost if the lifetime volume was only 10,000 units.

2005\05\12@115209 by J. Gromlich

flavicon
face
I plead guilty to not being in the low-end computer peripherals business.
Virtually all of my work has been in industrial and laboratory devices,
where you are a d___ fool if you don't try to cover every possibility of
"things" going wrong.  Wrong plug, wrong cable, wrong medium, too
much or too little light - the list goes on. The wrong medium was a bit
interesting - I'm not referring to the recording medium, but a carrier for
the test reaction.  Pour in the wrong medium and some time later there
will be a loud bang, a nasty smell and lots of small pieces of glass all
over your laboratory.  We were very careful about testing that one,
and trying to idiot-proof it.  So fat I haven't heard of one exploding,
so I guess we did it right.

And yes, I do know that no one repairs boards to the component level
any more.  I have written instruction sheets which tell the user to replace
the device if the self-test fails.

On the cost / price point - the scanner was $150 new.  I have used it
sparingly for two years, and it probably had a few more years to go.
The direct cause of the damage was working too late at night and in
too much of a hurry, so I can't blame them for that.  Any other time I
would just buy the newest, latest & greatest replacement, but this is
not a good time for it.

Anyway, though I have no real right to feel disappointed, I am.

RJG

>
> {Original Message removed}

2005\05\12@120930 by Alan B. Pearce

face picon face
>Let this be a warning to designers - don't rely on an external plug-in
>regulated supply alone to protect your hardware. Especially when using
>a standard plug & jack pair as would be found on any unregulated wall
>wart. Had this scanner had a voltage regulator on the main board, or a
>different type of power plug to the regulated supply, it would not have
>mattered if the wrong wall-wart was plugged into it. The regulator might
>have gotten hot and gone into thermal shut-down, or maybe popped a fuse.

I have seen worse than you describe. A company I worked for had a laptop and
one of those LCD displays you put on an overhead projector, both made by
Sharp. The two items had almost identical looking mains supplies with
identical connectors for the DC out, but one was reverse polarity to the
other. One day the inevitable happened while setting up a sales demo for a
very important client - result two very dead and expensive items.

If the laptop and display had been from different manufacturers you could
wear the different polarities out of the supplies, but when they came from
the same manufacturer ...

2005\05\12@122202 by Alan B. Pearce

face picon face
>That's exactly the point. A monitor, especially an expensive monitor,
>does still have an expectation of being "repairable", hence the fact
>that a service manual is available.
>
>But you ARE talking about an $80 scanner.
>
>> You could argue that there is a lot more IP in those
>> schematics than there is in the schematics of a $80 scanner, as there is
a
>> lot more non-trivial electronics.
>
>Remember, it doesn't MATTER how much "IP" there is in the schematics,
>it's the fact that there MIGHT be something "good" in those schematics
>that a competitor might be able to use that scares companies.

I think you guys are forgetting another factor in making something
repairable. The cost of stocking spares, and the cost of technical labour to
do the repair. This is another reason why so much repair is done by board
jockeys these days. A school kid could replace the PCB in the scanner, and
the cost of the spare is probably about $10 to the company, but to have a
technical person repair it plus stocking a range of spares for it is dearer
than a complete scanner - so they sell you a complete scanner as a
replacement, and have the schoolboys wages.

This is irrespective of any IP in the product.

The monitor has enough built in price to make the cost of individual spare
parts worth while, especially as many of the items will not necessarily be
on the PCB. it is also an item where there is a reasonable chance of an
observable rate of infant mortality failure, which the service organisation
will have to deal with to keep the company name. The scanner is cheap enough
and of a construction where the infant mortality will be negligible, and
complete unit swap for any that do fail.

2005\05\12@135024 by J. Gromlich

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face
OK - I think this is a dead issue in so far as the question I originally
asked of the board.  However, there are a couple of points here which
I want to discuss.

First, the scanner was list at $200 three years ago - not that cheap.
I got it for $150 on sale - 25% off list.

I have spent zero time with them on the phone - all communications
have been by email.

I didn't ask them to repair it - I told them on line one that it was over
two
years old and therefore obviously out of warranty.  It is a model which
was discontinued over a year ago.

I was not expecting to obtain spare parts from them. I am quite certain
that they have spares, but not for resale - nor would they be likely to
have their accounting set up to do parts sales. Actually, had I found
that one of the big SMT chips on the main board was the likely culprit
I would have been happy to buy a replacement PCB from them.

I didn't ask for a service manual - I agree that there probably is no such
thing, except as internal documents. From my experience those in-house
service notes can be very cryptic.

However, they obviously have schematics and board layouts for the
scanner - otherwise they couldn't produce and sell them.  All I wanted
was a copy of the schematic and layout so I would have a clue as to
what I was looking at during troubleshooting.  I offered to pay for the
copying and mailing.

While it is true that I could be a competitor, how much am I going to
learn from a design which is a least three years old?  And frankly, when
I have actually needed to know what a competitor was doing, we have
purchased one of the latest & greatest and taken it apart for study. You
can learn an awful lot that way.

Finally, while I understand that the best thing to do here is to kiss it
goodbye and buy a new one, that in not an option at the moment.  Time
to troubleshoot I have in plenty - money to buy a new scanner I do not.

[End of rant from my end.]

RJG

>
> {Original Message removed}

2005\05\13@012822 by William Chops Westfield

face picon face

On May 12, 2005, at 9:09 AM, Alan B. Pearce wrote:

> A company I worked for had a laptop and
> one of those LCD displays you put on an overhead projector, both made
> by
> Sharp. The two items had almost identical looking mains supplies with
> identical connectors for the DC out

cisco IP phones of some vintage apparently used a 48V DC power supply
whose connector is pretty much the same as the laptops in use at the
same
time (probably 16V.)  Entertainment happened when there was a big
building
move (throw your phone, keyboard, power supplies, etc into a box, then
take
them out at your new cube/office and put them back together...)

 :-)
BillW

2005\05\13@014706 by William Chops Westfield

face picon face
On May 12, 2005, at 10:50 AM, Roy J. Gromlich wrote:

> However, they obviously have schematics and board layouts for the
> scanner - otherwise they couldn't produce and sell them.

You're assuming a lot for the times.  Somewhere, probably deep in China,
is someone who once had schematics and board layouts.  But the product
may have come to your country as little more than an "OEM scanner
module"
with connection diagrams and minimal specifications (you've seen some of
what passes for LCD panel "documentation" from surplus dealers, right?)
If you bought it two years ago on sale, it was probably designed 5 years
ago at a company that may no longer be in business.  The company you
dealt
with may have done little more than slap on their label, written a
manual,
and done phone support; none of which requires schematics or PCB info.

Yeah, it's a bit sad.  It's why I keep telling myself to buy stuff
that's
well behind "state of the art", at deep discounts.  I mean, you can get
a
pretty good scanner for about $40 bucks these days, assuming it's not
part
of a $100 all-in-one printer/copier/scanner.

BillW

2005\05\13@074702 by olin_piclist

face picon face
William Chops Westfield wrote:
> Yeah, it's a bit sad.

I don't see anything sad about being able to buy a complex and precision
piece of equipment like a scanner for $80 when only about 10 years ago I
paid more like $900 for a decent scanner.  (It was an HP, back when that
still stood for quality as apposed to being a warning lable as it is today).
What you are seeing is a more efficient system than before, and naturally it
will look different.  The "good old times" of computing and most of the rest
of technology weren't really that good at all.  I'm glad that I don't have
to go back to the days of worrying about every Kbyte or Mbyte on the disk,
or whether we should spend several thousand dollars to add a few Mbytes of
RAM to the engineering computer that was time shared by 20 people and
getting 20 page fault per second.

2005\05\13@080859 by Gerhard Fiedler

picon face
William ChopsWestfield wrote:

> Entertainment happened when there was a big building move (throw your
> phone, keyboard, power supplies, etc into a box, then take them out at
> your new cube/office and put them back together...)

:)  That's why the first thing I do when an equipment comes with a wall
wart is to write the name of the equipment on the wall wart and put a label
on the cable near the plug (I keep most of my wall warts under the desk,
and usually want to know what cable belongs to what).

Gerhard

2005\05\13@095910 by J. Gromlich

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face
I totally agree that it is a good idea to keep track of which wall wart
goes to which device - I usually do that myself.  For instance, I have
the meLaboratories EPIC programmer, which uses a 16 volt wall
wart. This is a slightly odd value - the programmer won't work
properly with a 12 volt wart, while the 1 volt output might be too
much for devices with internal regulators. So it is labeled and kept
with the EPIC.

The problem here (Microtek) is that there is nothing anywhere on
the power module or on the scanner to indicate that there is anything
special about the combination - that using a different 12 volt wart
will likely kill the scanner.

Now, that warning IS on the website IF you go to the knowledge
base and ask "which power module does my scanner need?" - you
will get a list of models with their matching power units AND a
warning that using the wrong one WILL damage your scanner.  But
actually,  the fact that you are searching for info on power supplies,
suggests that the damage has already been done, only you don't
know it yet.

So my original opinion here stands - that manufacturers who do
things like requiring a specific power module for a specific device
model should make that very obvious - especially when a mistake
can cause destruction of the device. Label the case and module,
use different colors, use a keyed plug on the wall wart. Something.

But that's just my opinion - YMMV

RJG

>
> {Original Message removed}

2005\05\13@100559 by Michael Rigby-Jones

picon face
>-----Original Message-----
>From: spam_OUTpiclist-bouncesTakeThisOuTspamMIT.EDU [.....piclist-bouncesKILLspamspam@spam@MIT.EDU]
>Sent: 13 May 2005 14:59
>To: PICLIST
>Subject: Re: [EE]: looking for schematics or other info on
>Microtek4900scanner
>
>So my original opinion here stands - that manufacturers who do
>things like requiring a specific power module for a specific
>device model should make that very obvious - especially when a
>mistake can cause destruction of the device. Label the case
>and module, use different colors, use a keyed plug on the wall
>wart. Something.

Yep, they *should* do, but in a market where margins are very low then
the difference between a generic DC power socket and a special keyed one
are simply unacceptable.

Regards

Mike

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