[Mirrors]

Notes on the Troubleshooting and Repair of Computer and Video Monitors

Contents:


  13.60) Big Al's rules of thumb on monitor repair


1. Use an isolation transformer. A variac can be helpful too. A cheap isolation
   transformer can be constructed by wiring two identical transformers of
   adequate power capability back-to-back.  (Here is a use for those old
   boat anchors you can't bear to part with).

2. If it's just the power supply or flyback switching transistors that have
   failed, then the repair is probably easy enough and quick enough to be
   worthwhile. Blown power transistors are trivial to locate in the circuit
   and quite easy to find replacements for. In many cases I've found that the
   monitor would have lived a much longer life if only the transistor mounting
   screws had been tightened properly by the manufacturer.  Make sure you use
   appropriate replacements and the proper heat sink parts and heat sink
   compound.

3. If it's the flyback transformer, then judgement should be made based on the
   cost and availability of the replacement part. Also, on the risk of there
   being additional problems beyond that of the bad flyback. Who get's to eat
   the cost of the part in the event you don't succeed and give up?  However,
   determining that the flyback is indeed at fault may prove challenging
   without a flyback tester.  Sometimes there will be obvious damage such
   as burnt marks, cracked plastic, or other signs of overheating.  If you
   have the correct resistance measurements, then for the primary you may
   be able to detect shorted windings.  You can also construct the brute
   force flyback tester at the end of the document.

4. If it's the CRT then make the project "someone else's problem" and give the
   monitor to someone else to use as a parts carcass. My life is much happier
   since I learned there is no disgrace in making this choice.

5. There is another common failure category which is a result of people who are
   too lazy to turn off the power switch at night. The constant heat causes the
   electrolytic capacitors to dry out and become intermittent. I often replace
   all of the smallest electrolytics in the power supply section especially
   when I know the switching transistor is good. If after a couple of hours
   of labor and a dozen caps I still don't have it running, I give up on
   these too.

6. Be realistic with yourself about the value of a used working monitor. CGA's
   EGA's and monochrome Hercules monitors rarely fetch more than $25 at a swap
   meet.

7. Don't sell a used monitor to a friend unless you want to continue repairing
   the thing until you're old and grey.

8. Don't put a scope on the collector of the supply or flyback transistors,
   unless you have a special X100 high voltage / high frequency scope probe.


  13.61) Tic-Toc Tips


(From: Andy Laberge (tic-toc@wolfenet.com))

1.  When you go to discharge the anode of a picture tube make sure you
    hook up your ground first or you may get an unexpected surprise. I
    have.

2.  Picture tubes will hold their charge for a long time. In fact I
    have been bitten from a tube that was removed from a TV, discharged
    and allowed to sit for six months. Treat all picture tubes as though
    they were fully charged.

3.  There is a practical reason for using an isolation transformer for
    troubleshooting monitors besides the safety issue.  The primary side
    of the power supply is isolated from ground and if you start probing
    it with a grounded scope you will short out components that were
    perfectly good until then. It will cost you more time in trouble
    shooting and more money.

4.  When looking for real small cracks in a monitor board try to use a
    strong indirect light to keep the glare and reflections to a minimum.
    You can loose a crack in the glare. Cracks also hide underneath the
    solder mask (the green stuff).  I have scrapped away the solder mask
    and there pretty as you please is that little beggar.  Next you want
    to fix it; scrap more solder mask off the trace about 1/2" on both
    sides of the crack.  Brighten the copper using an ink eraser (it has
    abrasive grit in it).  Tin the exposed copper very well and then
    solder on a piece of bare tinned buss wire. This is sort of an
    acquired art.  Cut the bus wire about 6" long. Next bend the wire at
    90 degrees at the 5" mark you now have an L that is 1" on the bottom
    and 5" on the stem. Hold the stem and solder the bottom to the PCB on
    top of your excessively soldered crack.  Now just clip the stem off.
    You should now have a crack that is bridged by a soldered on wire
    which will give your cracked board the added strength that it needs.
    If there are near-by traces you should also check these for possible
    hairline cracks or the starts of some. On boards with high trace
    density this method may not be possible; in that case use small gauge
    (#30) Kynar covered wirewrap wire and solder it to the associated
    trace pads on opposite sides of the crack.

5.  Some connections won't take the solder very easily. In that case
    remove all the old solder with either wick or a solder sucker.
    Pre-tin the connector until it excepts the solder readily and then
    solder the connector and it's pad. If you don't do this you will end
    up with a cold solder joint underneath your new solder.

6.  If you are a person that is for some reason or other always moving
    or unplugging your monitor; go out and buy yourself an extension for
    your monitor signal plug. Hook the monitor signal plug to the extender
    and then use the male end of the extension plug as your signal plug.
    If you bend one of these pins it will be a lot cheaper then having to
    buy a signal plug for your monitor if you can find one.

7.  In some VGA monitors you may have video smearing with dark letters
    on a light background.  This maybe caused from some low value
    electrolytics (usually around 1 uf) that have gone bad in the video
    driver circuits. Usually you can check these in circuit with an
    oscilloscope or out of circuit with a capacitance checker.

8.  Other filament problems might be low voltage caused from a leaky
    filter capacitor in the filament circuit. The capacitor will dropped
    the filament voltage down.  A resistor can increase in value causing
    the filament current to drop off.  Both of these problems can give you
    a faded picture look. A filter capacitor that has opened up will give
    you a bright picture full of noise and that is hard to trace
    especially if you are looking for it in the video.

9.  Homemade degaussing coils can be made using three degaussing coils
    (out of junked monitors) in series that way you do not need a ballast
    load and it acts more like the heavy duty degaussering coils. They
    still get warm though.

10. When checking a focus control the main thing to look for here is
    that the best focus is not on one end of the control. If it is then
    your focus control block is bad or falling out of tolerance.

11. High voltage regulation circuits can give you some weird problems.
    One particular monitor would shut down when it went from high white
    screen to a black screen. High voltage will elevate when the screen is
    darker and sometimes exceed the high voltage safety limit activating
    the shut down circuit.

12. Changing out CRT's is more of an art that gets better with
    practice. Some color CRT's line right up with a new tube and some take
    over four hours experimenting with results that still do not fall
    within specs.

13. Capacitors in the primary of the SMPS may go bad and cause the
    shape of the switching pulse to be distorted; the SMPS becomes
    inefficient and causing over heating and lower voltage. Change the
    capacitors if they look bad; shrinking of the vinyl casing or leakage
    underneath (looks like a leaky battery in a radio). Capacitors with
    105 degree temperature ratings are recommended in power supplies
    instead of 85 degree types because of the self generated heat.
    Everything in the power supply is a suspect of failure. SMPS
    transformers can even fail although it is rare. Some produce
    a high audio frequency whine at times due to material oscillations and
    load conditions.

14. Metal film resistors can cause weird shut down and start up
    problems. These are usually found in the power supply over current
    sense circuits. These resistors check good cold but fail after
    applying heat to them. When cool they would seem to run all day but if
    heat is applied they fail faster.  The value of these resistors would
    fall between 100k and 500k usually.

15. A good flyback source: Component Technology 1-800-878-0540


  13.62) Monitor service and how to get some


A typical monitor warranty is something like: 2 years parts, 1 year parts
and labor (i.e. you have to pay for labor the last year of your warranty).
What should you do when you are totally unsatisfied with warranty service or
when your monitor blows up 1 day after the warranty expires.

(From material provided by a former head service guy for a major computer
sales/service company.)

The behind the scenes secrets to get what you want are to do one or a
multiple of the following:

1. Call the "Service" (it appears they really aren't) Department of the
   company you procured the monitor from, and kindly ask to speak with the
   Service Manager.  If they ask for your name, they will most likely pass it
   on, as well as your service history... The manager will be "not at his
   desk".  They will ask to take a message... say something like "I would like
   to discuss a service contract" (free money) or "I would like to speak to
   him about your firm's good service" (appeal to his ego).  These are
   positive things they like.  They person on the phone will get your # and
   you will hear back within maybe an hour or so.  Reason: Service people like
   myself live in a very, VERY negative world... in the back of our minds we
   like to hear good and hide from the every day bad.  He will call back
   thinking good and when you get him, you can either beat him up, or butter
   him up... depending on your personality or style.  The later is best.  The
   nicer you are to someone, the more they will do for you... treat him like
   you've known him for years... talk to him on a one on one type style...
   tell him what has happened in a very calm, relaxed mood... sit back and
   relax... imagine yourself as Jack Nicolson.(?)  Talk as long as you can...
   joke, talk about golf, whatever... The longer you are on the phone with
   him, the more likely he is to do something.

2. Hardball!  Tell'em you are going to call the Attorney General and get this
   monitor covered under the Lemon law in your state if they don't get it
   fixed NOW!  They will have to give you a new monitor if the machine
   has to be fixed under warranty more than 3-times in a 1-year period. 

3. Call the manufacturer.  Tell them your monitor is bad and that the company
   that sold you the monitor has sent it to for service multiple times and that
   you must have it fixed because it monitors a dialysis machine for a 5-month
   old baby with liver cancer and a broken leg or something like that... Pull
   their strings.  Kindly let them know you aren't pleased with the monitor
   and you would like to send it in personally... (yes! you can do this!)  The
   key acronyms are RMA# or RA# or MRA#.... they all refer to Return
   Merchandise Authorization number in some form.

4. (This one is from sam)  Threaten to plaster their miserable product
   name all over the Internet.  Note that I do not believe one should
   actually do this - posting whiney messages to a bunch of newsgroups is
   largely non-productive and may leave you open to legal repercussions.
   But, the threat will need to be taken increasing seriously as the
   importance of Internet as an international medium expands exponentially.

When you send it the monitor, the RMA# has to be on the box.  Call the
manufacturer at their 800 number.  Ask for Customer Service.  Tell them
the story (kindly) and say that you would like to get an RMA#. This is a
type of laundry ticket # they give you to track the monitor's progress...
and they report directly to you when you call the RMA department to check
on it's status.   If they won't do this for an individual person, ask for
an address of an Authorized Repair Depot.  You will have to call the repair
depot and get an RMA#.

Let them know you would like to deal with them directly.  I would use tip
(3) as a last resort, (just before I call the Attorney General).

I would also be careful of the game they may be playing: let the warranty
on labor run over so we can get some money.


  13.63) Shipping damage 1 why monitors are like basketballs


(From: Stephen Swann (swann@panix.com)).

Monitors are more prone to shipping damage than most other computer
components, and it doesn't help that they typically pass through several
people's hands (several stages of shipping) before they get to you:
factory -> distribution center -> vendor -> you.

And from what I've seen first hand of shipping practices (I put in a
couple of months working in a distribution warehouse during college),
you can safely assume that each stage of shipping is roughly the
equivalent of your monitor being dropped down a flight of stairs.

You wouldn't *believe* the abuse that UPS and FedEx can subject
packages to.  In fact, putting a *FRAGILE* sign on the side of the box
is about the equivalent of writing "KICK ME" on it.  I remember
receiving packages marked "FRAGILE" where the (originally cubical)
cardboard boxes had been smashed into shapeless cardboard "bags", and
it took us 20 minutes to figure out what the contents of the box had
originally been.  ("What are all these shards?"  "I think it was some
kind of vase" "No, it was some kind of lamp."  "Where's the bulb
socket, then?"  "How about this squashed piece of aluminum?"  "Yeah,
you're right, but where's the cord then?"  etc).  :-) Shipping guys
would think nothing of dropping "fragile" boxes from waist-high onto a
concrete floor - safe in the knowledge that the package had passed
through so many hands that the damage could never possibly be traced
back to them.  "Blameless is Guiltless" should be the motto of these
folks.

Basically, what I'm saying is that if 1 monitor in 3 arrives arrives
in workable condition, you should be surprised that even that one
monitor survived.


  13.64) Shipping damage 2 why monitors are like hammers (as in throw)


(From: Steve Cunningham (swc@tamu.edu)).

Yes folks!  As a training exercise for the 2002 Summer games, Bill Baxter (not
his real name), a union thug from United Parcel will attempt to beat the
steroid enhanced monitor-throw record of 55 1/4 feet set by Udo Schrank of the
former East Germany.

But seriously folks--UPS and I just "go round 'n' round!"  Over the past two
years, they have broken about one third of the monitors shipped to us, even
those packed in the original polystyrene foam.  One monitor had the case
shattered, and the tube neck sheared off--even though the monitor was packed
securely in the original box and foam.  The stock response from UPS is that
"it probably wasn't packed securely," or some such drivel, while ignoring the
obvious--they are careless with fragile merchandise.

The latest outrage was when I was taking a short nap in my house (I work out
of my house), and a very loud crashing sound startled me awake.  My wife said
that it sounded as if someone was crashing through the front door.  Turns out
that the UPS dude dropped a $2000.00 70 pound 20" Ikegami monitor from waist
level to the ground, hitting the front door in the process.  After cooling
off, I carefully inspected the monitor, and, amazingly, it wasn't destroyed (I
have witnessed monitor boxes dropped from the airplane to the ground).

To add to the outrage, when I was ready to return the repaired monitor, the
local UPS manager made me purchase a new box, and have foam injected into it,
at a cost to the customer of about 50 bucks, before they would consider
shipping it (the old box was dented, but no worse for wear).  In a remarkable
bit of restraint (if I don't say so myself), I calmly walked out of the UPS
office (after waiting in line 30 minutes), and used a remailing company in the
area to ship it via UPS at an additional fee.  The customer received the
monitor a few days later, and yes, it was broken.  All of this despite being
packed with several inches of hard foam, and in a new, sturdy, 27" Uhaul TV
box.  The package arrived at the customer's place of business upside down,
despite up arrows.

I realize that they are a discount shipper, but, they are not paid to merely
ship packages.  They are paid to ship them in one piece.  If they can't do
that, I think that they should get out of the business and quit running an
insurance scam.  I can't return repaired monitors to people with the screws
missing, saying, "it's because I'm a discount servicer."  There is a minimum
level of quality that is acceptable.  Sometimes the lowest price is not the
best value.  As in all things human, let the buyer beware!  Hopefully someone
will find this useful to that end.  We won't be using UPS anymore.


  13.65) Shipping damage 3 why small monitors are like footballs


(From: Captain Mocha (CaptainMocha@Electra.com)).

I used to work for UPS, I loaded the trucks.

It's amazing you get anything in one piece when shipping with UPS.  There are
so so so so many packages that need to be loaded in those trucks in just three
hours per work shift.  The floor managers would encourage us to get the trucks
loaded in 'any way possible'.

We used to treat the small packages as 'footballs' and try to throw them
through box "goals" from the other end of the truck.  We also did 'punt
kicking' etc.

So get your facts straight!!  It's not 'Hammer Throwing', it's football! =)

(From: Michael Schuster (schuster@panix.com)).

A friend used to work in Manhattan, NYC and during lunch hour he often passed
the large camera/electronics retailer, 47th Street Photo, just as the UPS
truck was unloading.

It was common for this to be accomplished by having the driver stand in the
truck, and KICK the boxes to the ground one by one. So you see, it isn't a
hammer throw... It's football (or soccer) that they're modeled after.


  13.66) Shipping damage 4 so maybe if monitors were packed and shipped like eggs


"After receiving my third crunched monitor this week, I've about had it with
 these "Brown Shirted Box Stompers-in-the-mist!"  You would think that a well
 packed 14" clone monitor would survive a 30 mile journey while in their very
 incapable hands.  Actually, I should apologize to Jane Goodall, or whoever
 that Gorilla babe was--her objects of study would probably be much more care
 with monitor boxes than the knuckle-walkers at UPS.  I have been thinking of
 doing my own study as to what deceleration it takes to do the damage to a
 monitor that they have done.  My guess is that they must have to drop the
 thing on concrete from 5 to 7 feet high!  I've seen high impact cases
 shattered, tube necks sheared off, board cracked in half--sheesh, where do
 they get these guys?  From a zoo?  Sure, they reimburse the owner, but I lose
 the repair fee.  Does anyone know if can make a loss claim also?

(From: David Rouse (david.rouse@engineers.com)).

Actually they are probably only being normally clumsy. It probably is the
packaging of the monitor that is causing the failures. A monitor is a fragile
thing. It only takes about 50 g's of acceleration to kill one. This translates
into about a 3-4 inch drop onto a hard surface. The packaging is supposed to
protect it by spreading the shock pulse out over a longer time period. Alas,
though, all styrofoam (or whatever is being used for cushioning) is not
created equal. The maker was most likely trying to save a couple of pennies
and use something a little too rigid. The wrong material can provide too
little cushioning and in some cases even amplify the shock transmitted to the
product under the right(or wrong) circumstances.  FYI Trinitron tubes have
really bad shock characteristics.


  13.67) Cleaning plastic monitor cases


For surface contamination like grease or tobacco smoke, a variety of household
cleaners will work including Fantastik, Windex, 409, etc. - some better than
others depending on the type of coating.  Verify that whatever you use is
safe for the plastic by trying it out on an inconspicuous location first.

For ozone or heat damage which penetrates deeply into the plastic, painting
may be the only a solution.  Test on a non-visible section to see how deeply
the discoloration has penetrated.  For modest discoloration, I have had some
success with water and scouring powder containing bleach.


  13.68) Secret menus


"I've seen some tantalizing references to the SECRET menu for adjusting
 VisionMaster Pro 17 monitor secret menu.

 Could someone kindly point me to some details so that I can access and
 properly use this covert functionality?"

(From: Scot Miller (scot@cts.com)).

Shut the power off, then switch it back on while simultaneously holding down
the 'menu', '-', and '+' buttons.  Then the 'menu' button works normally but
will bring up the secret menu.


  13.69) Reliability and performance of refurbished or remanufactured monitors


"Considering a 21-inch monitor and have seen a number of resellers beginning
 to carry refurbished monitors.  Under most circumstances I would walk right
 past anything refurbished for the shiny new model, but at the price of new
 21 inchers, well...   Monitor would be used primarily in Windows and for
 playing Quake.  Locally I'm seeing prices of $1100.00 to $1300.00 with a
 2 year warranty for 1st & 2nd tier products.  Feedback, anyone?"

Assuming you can fully test drive it and/or get a money back no questions
asked warranty, then they are worth considering.  The most critical issue
is the condition of the CRT make sure it is bright, sharp, and has no screen
burn.  If the CRT is in good condition, then there is no reason to think that
the rest of the monitor will fall apart or go up in smoke.  Note: Test from 
a power off for at least an hour condition.  Once an old CRT warms up, it may
appear to be better than it actually is.  See the document: "Performance
Testing of Computer and Video Monitors" for additional evaluation criteria
but be warned that no monitor is perfect - some 'defects' you find may be
inherent in the design or simply due to normal variations in manufacturing
quality control.

The two terms 'refurbished' and 'remanufactured' may be mean the same thing.
However, it would probably be worth trying to get a clarification in writing
of exactly what was done to the monitor.  Depending on the integrity of the
reseller, these terms could mean anything from 'well, we turned it on and
it didn't blow up' to 'unit was completely overhauled and restored to new
specifications replacing parts where necessary'.


  13.70) Ron's notes on video signal quality problems


From: pinecone@pacbell.net (Ron)

Here are some possible causes for ghosting, smearing, etc.:

1. A poor quality video cable.

2. A video extension cable (making the cable longer always makes things worse).

3. Running the video card and/or monitor too close to their maximum bandwidths.

4. Impedance mismatch between the video card and the monitor.  Most cards,
   monitors, and cables are 75 ohms, but 50 ohm parts exist.

6. Bad video card. I've seen many video cards with this problem, and a
   manufacturer recently admitted to me that one revision of their board has
   a grounding defect that causes...ghosting.

7. Bad monitor. I think this is unlikely. Usually poor monitors produce muddy
   images that hide ghosting, if indeed there is any.


  13.71) Monitor quality control


(From: Bob Myers (myers@fc.hp.com)).

The bottom line is that I've been involved with the design, manufacture,
specification, and purchase of CRT displays for longer than I care to admit,
and I can tell you one thing with absolute certainty: it is IMPOSSIBLE to
maintain visibly perfect geometry, linearity, etc., on the things over a
production run.  You can spend hours and hours getting a given unit to look
pretty darn good, but even that is iffy - it depends to much on the limitations
built into that particular CRT and yoke.  And even if you CAN get that unit
'perfect', this ISN'T something that you can do in normal production - not
unless you find customers willing to pay SIGNIFICANTLY higher costs for the
products.  Despite claims to the contrary here, that has NOT been the desire
expressed by the market. 

(From: Gary Flynn (gary@habanero.jmu.edu)).

Many years ago I did TV repair and there were LOTS of adjustments available.
I haven't cracked open a TV or monitor lately but your statement about CRT
and yoke limitations jogged my memory. Are most monitors today "rack and stack"
or are there internal factory adjustments? Having just ordered a 17" Trinitron
based monitor and having confidence in my old TV abilities makes me want
to explore :-)

(From: the editor).

No, you will not find many of these sorts of twiddles in modern monitors.
Most purity, convergence, and geometry adjustments are via strategically
placed magnets glued to the CRT, the orientation of multiple magnetized
rings, the position and tilt of the deflection yoke, etc.  You really do
not want to mess with these unless you have no choice and lots of time.

Many modern monitors control the picture adjustments via hidden menus and
digital controls.

The 'good old days' are gone forever... :-) :-(.


  13.72) Is Big Brother watching over your shoulder?


"Does anyone out there know how the Timex/Microsoft watch is programmed by 
 holding the watch in front of a VGA monitor.  There must me some sort of
 sensor on the watch that picks up some sort of pattern on the screen retrace
 of the monitor...."

(From: Len Turnbow (quartlow@netcom.com)).

I know nothing about the Timex/Microsoft VGA optical communications protocol.
But, sometime when you have nothing better to do, you might connect a
phototransistor to a biasing source and thence to your oscilloscope.  Aim
phototransistor at your  computer monitor and check out all the weird patterns
produced as a result of various screen displays.  

Before long, you will note that the leftmost edge of your scope display
represents information present near the top of your screen.  If you have
your trigger properly set, you will also note that the whole contents of
the screen are presented (top to bottom) on your scope (left to right).

With a blank white raster, you will be able to move your hand in front of
the screen and see the result on your scope a la flying spot scanner.  But
I digress.

Armed with a borrowed copy of the Microsoft interface software and your
phototransistor, you could probably reverse engineer the protocol.  

Or ask someone at Microsoft.com :-).  What would be the fun in that, though?


  13.73) Lament of the lack of adjustment pots on the newest monitors


In 'the good old days' before digital controls and service menus, one could
spend a substantial fraction of one's life tweaking monitor adjustments.
The newest monitors (and TVs) are nearly totally controlled by settings
stored in EEPROM.  The service adjustments may only be accessible via a
port connection to a PC running a special manufacturer specific setup
program.

This is the wave of the future and we are stuck with it for better or worse.
In all fairness, digital adjustments are less costly to manufacture and permit
much more automation in the factory setup of screen geometry, color, and so
forth.  However, not making the setup software available for a reasonable
licensing fee is a serious problem which will result in lost opportunities
for smaller independent repair shops.

(From: CiaraTom (ciaratom@aol.com)).

The point is that each manufacturer has written a program for his monitor to
tweak things that we used to do with a screwdriver.  It is model specific, not
generic, and often requires an interface (special cable, with or without
circuitry in between) sometimes connecting to your parallel port, sometimes
to the serial.  

Goldstar does this with a special proprietary software and special cable; 
Viewsonic has (that cost me $220 - try to recoup that from a repair) and
it is so user unfriendly that you don't even know what to do with it.  


  13.74) Analog versus digital LCD flat screen monitors


(From: Bob Myers (myers@fc.hp.com)).

This refers to the interface to the monitor, with "analog" generally meaning
that it can plug directly into the same video connector as your typical CRT
monitor.  Digital-input monitors have in the past required special interface
cards, but there are new standards for digital video outputs (such as the VESA
"Plug & Display" connector family).  The displays themselves (the inner
workings aren't REALLY "inherently digital" either - although the interface to
the panel itself usually is - but they ARE fixed-format devices, which brings
along its own set of problems.

Digital interfaces, assuming you DON'T need a special interface card in the
PC, will be less expensive than analog interfaces and will offer better
performance.  The performance increase doesn't come so much from having the
information provided in "digital" form, but rather from having accurate timing
information available.  The biggest headache in designing an analog interface
for these monitors is trying to generate the correct clock for sampling the
incoming video.  It's usually been done by multiplying the horizontal sync
rate up to the proper frequency, but that is hard to do with REALLY good
stability, and the phase relationship between the H. sync signal and the video
isn't all that reliable.  This makes for an unstable display, with what looks
like considerable noise (especially when you have lots of single-pixel
details).


Chapter 14) Service Information



  14.1) Advanced monitor troubleshooting


If the solutions to your problems have not been covered in this document,
you still have some options other than surrendering your monitor to the
local service center or the dumpster.

(Also see the related document: "Sources of Repair Information and General
Comments".)

Manufacturer's service literature:  Service manuals may be available
for for your monitor.  Once you have exhausted other obvious possibilities,
the cost may be well worth it.  Depending on the type of equipment, these
can range in price from $10-150 or more.  Some are more useful than others.
However, not all include the schematics so if you are hoping to repair an
electronic problem try to check before buying.

Inside cover of the equipment:  TVs often have some kind of circuit
diagram pasted inside the back cover.  In the old days, this was
a complete schematic.  Now, if one exists at all for a monitor, it just
shows part numbers and location for key components - still very useful.

SAMs Photofacts:  These have been published for over 45 years but have
never been common for monitors.  There are a few for some early PC
monitors but for anything modern, forget it.

Whatever the ultimate outcome, you will have learned a great deal.
Have fun - don't think of this as a chore.  Electronic troubleshooting 
represents a detective's challenge of the type hat Sherlock Holmes
could not have resisted.  You at least have the advantage that the
electronics do not lie or attempt to deceive you (though you may
beg to differ at times).  So, what are you waiting for?


  14.2) Additional information


For general information on PC video cards and monitors, see the
comp.sys.ibm.pc.hardware.video FAQ.  This relatively new document
has wealth of data on nearly everything you could possibly want to
know about video for the PC world.

(From: Michael J. Scott (mjscott@heartlab.rri.uwo.ca))

The FAQ is available via ftp and the WWW:

To ftp a text-only version of this FAQ, and/or the chipset list:

Compressed Video FAQ at 
ftp://ftp.worcester.com/pub/PC-info/pc-hardware-video-faq.Z

Compressed Video Chipset List at
ftp://ftp.worcester.com/pub/PC-info/pc-hardware-video-chipsetlist.Z

A WWW version (Netscape enhanced) is available at: http://www.heartlab.rri.uwo.ca/videofaq.html

Uncompressed and compressed (pkzip, gzip, compress) text versions are also
available at the web site.

The FAQ has received news.answers approval, so it should be archived at 
rtfm.mit.edu and all mirrors, as well as in news.answers and comp.answers.

Contributions, questions and corrections always welcome and appreciated.


  14.3) Suggested references


There don't seem to be that many readily available books on monitor repair.
Here are a couple:

* Troubleshooting and Repairing Computer Monitors
  Stephen Bigelow
  McGraw Hill, 1995
  Hardcover, 304 pages
  ISDN 0-07-005408-8

Some of the topics are

  - CRT alignment and degaussing
  - State-of-the-art plasma displays
  - Specifications and architectures of monochromw, CGA, EGA, VGA, and SVGA
  - Linear, switching, and high voltage powersupplies
  - Logic and drivers supporting both CRT and LCD monitors
  - Graphics standards
  - Sample schematics

* Computer Monitor Troubleshooting & Repair
  Joe Desposito
  Howard W Sams & Co, 1997
  ISBN: 0790611007 

Also, since monitors share much in common with color TVs, books on their
repair would also be applicable for many problems - and may be more readily
available from your local public library.

There don't seem to be nearly as many TV repair books for modern solid
state TVs as I recall for old tube sets.  Here are is one suggestion
which you may find (or its predecessor) at your local public library
(621.384 if you library is numbered that way) or a technical book store.
MCM Electronics has this as well.

Troubleshooting and Repairing Solid State TVs
Homer L. Davidson
2nd Edition, 1992
TAB Books, Inc.
Blue Ridge Summit, PA 17214

(From: Skip (skipperm@mtc2.mid.tec.sc.us))

I recently attended a monitor repair course put on by Philips electronics.
They have a technical training manual titled 

        HI-RES COMPUTER DISPLAY SYSTEMS
        part # ST1496-1093LE/KGPGC

I am sure this can be ordered from Philips Service Co.
P.O. Box 555, Jefferson City, TN 37760  phone 423-475-0044

This book does an excellent job of explaining how these monitors
work. Most is about Philips monitors but the material is applicable
to most manufacturers. This course and reading this text has
help me a lot with my monitor repair efforts.

The following doesn't specifically deal with monitors but may be of interest
as well:

"Video demystified: A handbook for the digital engineer", Keith Jack,
Brooktree Corporation, 1993 (ISBN 1-878707-09-4).

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Written by Samuel M. Goldwasser. | [mailto]. The most recent version is available on the WWW server http://www.repairfaq.org/ [Copyright] [Disclaimer]