Capacitors repair on an LCD monitor are these Caps good ones?


G

Gabriel Knight

Hi and Merry Christmas!!, I have a Samsung Syncmaster 2493HM LCD 24" monitor
that will not turn on for a while when the power button is pressed but
everything else is fine as the picture on screen is not bad or does not
flicker so the inverter board should be good but from googleing the power
boards capacitors need replacing. This site below says how to do it and that
I can buy a kit from them :

http://www.ccl-la.com/blog/index.php/reparing-a-samsung-2493hm-24-lcd-monitor/

but are their caps good ones or can I get better ones somewhere?

On their site is this page:

http://www.ccl-la.com/blog/index.php/capacitors/

the above talks about what good caps are. Im using the monitor in question
right now for making this post but as I said when I turn it off for some
houres in time it takes a while to turn on. To my understanding the caps get
heated up from the monitor and become faulty or is samsungs caps not a very
good quality either way is the kit from above going to be good lasting
quality for the heat rating or should I look for some with better heat
handeling? Thanks all, GK
 
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P

Paul

Gabriel said:
Hi and Merry Christmas!!, I have a Samsung Syncmaster 2493HM LCD 24" monitor
that will not turn on for a while when the power button is pressed but
everything else is fine as the picture on screen is not bad or does not
flicker so the inverter board should be good but from googleing the power
boards capacitors need replacing. This site below says how to do it and that
I can buy a kit from them :

http://www.ccl-la.com/blog/index.php/reparing-a-samsung-2493hm-24-lcd-monitor/

but are their caps good ones or can I get better ones somewhere?

On their site is this page:

http://www.ccl-la.com/blog/index.php/capacitors/

the above talks about what good caps are. Im using the monitor in question
right now for making this post but as I said when I turn it off for some
houres in time it takes a while to turn on. To my understanding the caps get
heated up from the monitor and become faulty or is samsungs caps not a very
good quality either way is the kit from above going to be good lasting
quality for the heat rating or should I look for some with better heat
handeling? Thanks all, GK
Nichicon and United Chemicon are generally good.

I've heard of the odd Nichicon going bad. Not very many. It's
possible to make electrolytics fail, by mis-applying them
(running too much ripple current through them).

An issue with caps, is counterfeiting. There isn't much to identify
who made them, when they slide a plastic sleeve over the aluminum
to identify the product. It isn't hard for a Chinese shop to
take an un-sleeved capacitor, and make their own sleeves for them
(with anything they want printed on them). Which means, if you're
buying them, you need to deal with someone you can trust to buy
them from the actual company. (There is at least one web
site, where they track reports of counterfeiting, to help
others in the industry to be more careful about who they
buy from.)

With any capacitor company, they make multiple lines of capacitors.
It's kinda hard sometimes, to figure out why they bother with as
many lines of products as they do. Each line has a different
temperature and "thousands of hours" rating. You use the
Arrhenius relationship, to re-rate the caps to a similar
temperature. And then you can select the one with the most
hours at that common temperature. That's how you identify
the best lines of them.

Performance is related to volume. A typical situation you
might find on a motherboard, is caps that are "one size too small".
When you go to buy a substitute, all the substitutes of that
voltage and capacitance rating, are one size too large and
won't fit. That's generally a sign the original parts probably
weren't all that good. A claim I've read is, the companies
that make the caps are pretty well matched on the performance,
so all the sizes of the caps should be similar. If a cap is
"impossibly small", generally it means some parameter has
been compromised.

In terms of doing substitutions, you can't just run off and
substitute anything you feel like. Some switcher designs,
the design is "centered" on "midrange" quality caps, where
the ESR isn't that low. A natural temptation might be
to say "oh, I can replace all of those with one Oscon".
If you do that though, you should go through the datasheet,
and rework the equations, and see if the predicted performance
is still adequate. The application section of the switcher
chip datasheet, will usually have a section on capacitor
selection, which is where I learn about these things.
Now, someone selling a "capacitor kit", might be
Albert Einstein. Or, they might be some pimply
teenager with a nose for business. Your job as
the buyer, is to decide what kind of person this is.
Chance are, they won't be stupid enough to sell you
Oscons because they feel they have superior ratings.
They should be replacing "like with like", in terms
of the "class" of the capacitors. If the original
capacitor was a "switching" class capacitor, the
replacement should be too. (i.e. Nothing you can
buy at Radio Shack, is even close :) Even my "good"
electronics store, doesn't have good caps.)

If you want to understand more about this, you'd download
the Nichicon product overview for electrolytics, see
some rated for "switching supplies" and so on. Then see
which families are used in the capacitor kit you're
buying.

Not all the caps on a board, are part of switching
regulators. Some are simple bulk capacitance, for
improving transient response to step loads. They're
"sprinkled" across a board. There's a limit to
how many you can use, because the power supply
feeding the board, is only stable up to some number
of thousands of microfarads of load. Some of those
caps, might not be subjected to the same level
of abuse as the ones in the switching regulator.

You can run enough amps of ripple current through
a cap, to actually heat it up. They use a bunch in
parallel, to share that current. In some cases,
the actual capacitance value isn't all that important,
and the tolerance on total capacitance is sloppy. Not
the same, as if you had an RC timing circuit, and
the value of R times C was critical. In a switcher,
the desired property might be ripple current
rating, as much as anything. If the capacitance was
off by 30%, the transient response would be a little
different, but it probably still works fine. So if
you had a 2200, and only an 1800 at the same voltage
was available, it's probably OK to use it. So
don't freak out, if the capacitor kit happened to
substitute an 1800 for a 2200. They can't go too
far in one direction, because the size of the
aluminum can won't fit. If the original was
"impossibly small" to begin with, they might have
no choice but to sub an 1800 for a 2200. Because
any decent 2200 might be too big to fit.

On the PCBs, I'll never figure out why the caps
have to be touching. They should leave some
clearance around them, to make it easier for
the factory to purchase substitutes. The only
reason for making them touch, is if you plan to
glue them together to make them resistant to
vibration (like you have to do for caps in a
sub speaker+amp). In a monitor, I doubt the
caps are going to be glued to each other
for moral support. They could spread them
out a little more, and leave room for "one
can size larger".

Paul
 
L

larrymoencurly

I have a Samsung Syncmaster 2493HM LCD 24" monitor that will not
turn on for a while when the power button is pressed but everything
else is fine as the picture on screen is not bad or does not flicker
so the inverter board should be good but from googleing the power
boards capacitors need replacing. This site below says how to do it
and that I can buy a kit from them :

http://www.ccl-la.com/blog/index.php/reparing-a-samsung-2493hm-24-lcd-monitor/ >
but are their caps good ones or can I get better ones somewhere?
On their site is this page:
http://www.ccl-la.com/blog/index.php/capacitors/
the above talks about what good caps are. I'm using the monitor
in question right now for making this post but as I said when I
turn it off for some houres in time it takes a while to turn on.
To my understanding the caps get heated up from the monitor and
become faulty or is samsungs caps not a very good quality either
way is the kit from above going to be good lasting quality for
the heat rating or should I look for some with better heat
handling?
The website says,

"We exclusively use Nichicon and United Chemicon Capacitors
in our repair kits and in house monitor repairs."

Those are very good brands, except for Chemicon's models KZG and
KZJ. It's not enough to get capacitors rated for 105 Celcius instead
of 85 Celcius; they have to be good brands, too. Apparently all
Japanese brands are good, except for those model Chemicons and a
brand called TK (Toshin Kogyo). I think the only good non-Japanese
brand is Jamicon.

Nichicon had loads of problems with their HM and HN capacitors back
around 2002-2004, affecting Apple, HP/Compaq, and Dell but that problem
has been solved completely.

If you buy from an Ebay dealer, apparently the only legitimate one is
the PC Motherboard Capacitors Store, although they sell both good and
bad brands. This dealer and DigiKey.com are good for small orders
because the shipping charges are low. About everybody else on Ebay
sells counterfeits, and I've also seen counterfeits at DealExtreme.com.

http://www.BadCaps.net has loads of information about capacitors
and electronics, including a forum just about video monitor repair.

Be sure to resolder the leads of the transformers.
 
G

Gabriel Knight

Hay thanks paul and LMC (larrymoencurly) LMC do you know if this seller from
ebay would or is turstable:

http://www.ebay.com.au/itm/330549799415?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

he says he is selling good brands but I would like to know from you first
and to see if they are counterfeit, I went to www.digikey.com and looked at
their capacitors but what type do I order? there are lots to choose from:

a.. Accessories (93 items)
b.. Aluminum Capacitors (65352 items)
c.. Capacitor Arrays (1362 items)
d.. Ceramic Capacitors (125930 items)
e.. Electric Double Layer Capacitors, Supercaps (639 items)
f.. Film Capacitors (19845 items)
g.. Mica and PTFE Capacitors (3000 items)
h.. Niobium Oxide Capacitors (469 items)
i.. Silicon Capacitors (177 items)
j.. Tantalum Capacitors (50330 items)
k.. Thin Film Capacitors (2373 items)
l.. Trimmers, Variable Capacitors (689 items)
I looked at the power board for the monitor and I see no traces of bad caps
none of them are buldging or have residue around them but on the board that
has the connections for the video cable ie HDMI, analog and digital I can
hear a small ball bearing like thing moving when I move the PCB around, I
have looked and looked and tried my best to hear where it is but I cant find
it, it sounds like it is under one of the surface mount caps as the board
only has surface mount type caps on it plus a "crystal" (i think this is for
timing of the interupts) like I see on motherboards it is the length for a
small ball bearing to move around and to make the noise I hear, Or is this
sound I can hear ment to be there? If so what is it? I can now no longer use
the monitor as when it does finaly turn on about 2 seconds later it powers
off. Thanks lots, GK.
 
P

Paul

Gabriel said:
Hay thanks paul and LMC (larrymoencurly) LMC do you know if this seller from
ebay would or is turstable:

http://www.ebay.com.au/itm/330549799415?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

he says he is selling good brands but I would like to know from you first
and to see if they are counterfeit, I went to www.digikey.com and looked at
their capacitors but what type do I order? there are lots to choose from:

a.. Accessories (93 items)
b.. Aluminum Capacitors (65352 items)
c.. Capacitor Arrays (1362 items)
d.. Ceramic Capacitors (125930 items)
e.. Electric Double Layer Capacitors, Supercaps (639 items)
f.. Film Capacitors (19845 items)
g.. Mica and PTFE Capacitors (3000 items)
h.. Niobium Oxide Capacitors (469 items)
i.. Silicon Capacitors (177 items)
j.. Tantalum Capacitors (50330 items)
k.. Thin Film Capacitors (2373 items)
l.. Trimmers, Variable Capacitors (689 items)
I looked at the power board for the monitor and I see no traces of bad caps
none of them are buldging or have residue around them but on the board that
has the connections for the video cable ie HDMI, analog and digital I can
hear a small ball bearing like thing moving when I move the PCB around, I
have looked and looked and tried my best to hear where it is but I cant find
it, it sounds like it is under one of the surface mount caps as the board
only has surface mount type caps on it plus a "crystal" (i think this is for
timing of the interupts) like I see on motherboards it is the length for a
small ball bearing to move around and to make the noise I hear, Or is this
sound I can hear ment to be there? If so what is it? I can now no longer use
the monitor as when it does finaly turn on about 2 seconds later it powers
off. Thanks lots, GK.
Is it possible the crystal broke, and is loose inside its housing ?

If you have a webcam, take a picture of the assembly, and post
it on your favorite image hosting site. I use imageshack.us but
there are others which support worldwide hosting. Like maybe Picasa.
Upload the photo, then share the URL with us so we can have a look.

The electrolytic should have a rubber "plug" in the bottom of
it, so there should not be a ball bearing noise coming from that end.
The two wires, poke through the rubber. The aluminum can is
compressed on the end, to help hold the plug in place.

As for shopping at Digikey or Mouser, I doubt very much you'll find
good capacitors on there. There is also Newark (I've bought some
stuff from them recently). Newark used to be renowned for high prices,
but I actually got a "deal" on some stuff. (I think Newark is now
owned by a different company, so things have changed.)

The trouble with those sites, is how you search for stuff.
It takes me several days of work, to make up the simplest
of orders.

But really, I have low expectations when it comes to North
American sellers. You can try looking, but I wouldn't
expect to find good stuff on there. In some cases, the
parts weren't even located in the correct section of
the site. You have to get "lucky" some times, to find
what you're looking for.

Paul
 
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M

Michael Black

I looked at the power board for the monitor and I see no traces of bad caps
none of them are buldging or have residue around them
The bulging capacitors are a dead giveaway, but that doesnt' mean
capacitors that look fine are good.

I found an Acer 19" monitor almost two years ago on a crowded downtown
street, in front of a grocery store. I dragged it home, it nominally
worked in that it came on and displayed the Acer logo. I hooked it up to
a computer, it seemed fine. But then when I left it running, it went back
to displaying the logo, as if it had been turned off and on again, or put
in a low power mode.

So I opened it up, one good thing about LCD monitors is that they are
generally much easier to fix. Unless you want to start playing with the
backlight, you can acess the electronics and the power supply very easily,
unlike CRT minitors where you have multiple boards around the CRT, and
often not long enough wires to access theme easily out of the cabinet (and
still working).

The capacitors in the power supply didn't bulge, but it sure seemed to be
there, something resetting. So I just replaced many of the capacitors
that were there for filtering. I wasn't even fussing, wanted to get the
monitor going instead of the usual "open it up, find some details, then
let it sit open for months until I get the parts" so I just pulled high
temperature electrolytics off some scrap boards (not good since I didn't
know for sure that they were good, but I was in the mood to try) and put
it back together and it was fine. I'd thought of throwing together an ESR
meter to check for the bad capacitors, but that would take time, probably
need to buy some part for the project, so this was the route I took.
Likely not all the capacitors were bad, but for the moment and in a rush,
it was simpler.

Michael
 
M

Michael Black

But really, I have low expectations when it comes to North
American sellers. You can try looking, but I wouldn't
expect to find good stuff on there. In some cases, the
parts weren't even located in the correct section of
the site. You have to get "lucky" some times, to find
what you're looking for.
I'd argue that the places selling capacitors to fix specific monitors are
simpler simplifying the process. They have to be buying from big
distributors, and so what they save you is finding the needed capacitors
(for the novice they may not know) and buying in large quantities for a
better price, or because the distributor wont' sell in small quantities.
The person buying from such outlets pay a premium for the capacitors, but
may end up paying less since they don't have to fulfill a minimum order or
something. And someone has done the work to decide what capacitors need
replacing.

Michael
 
L

larrymoencurly

LMC do you know if this seller from

ebay would or is turstable:


http://www.ebay.com.au/itm/330549799415?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649


he says he is selling good brands but I would like to know from you first
and to see if they are counterfeit, I went to www.digikey.com and looked at
their capacitors but what type do I order? there are lots to choose from:

a.. Accessories (93 items)

b.. Aluminum Capacitors (65352 items)
I'm not familiar with that Ebay dealer, but it may help if you can
get pictures of their capacitors and compare them to the illustrations
given here:

http://capacitor.web.fc2.com/

Each electrolytic capacitor has a pattern stamped on top, to let it
explode more safely (really), and that pattern may help identify
fakes, emphasis on "may". For example, DealExtreme.com has
sometimes offered Sanyos, which are normally stamped with a "K" or
funny cross that looks like "><", but DealExtreme's were stamped
with 3 equal pie slices with a dot in the middle of each slice
(Teapo, an inferior brand) or with an ordinary "X" or "+" (probably
the most common stamping pattern, used even by some good caps).
There was one Ebay dealer that sold counterfeits with new heatshrink
plastic over them and over the original heatshrink.

You want choice "b", the aluminum capacitors. Places like Digi-Key and
Mouser let you specify about 10 different parameters, but it's best to
specify just the capacitance and voltage because their online catalogs
don't let you specify the maximum temperature without also specifying
the minimum temperature or the diameter without also giving the height.
I don't understand why modern computerized catalogs are so much slower
to use, compared to paper catalogs. And while low ESR and impedance are generally good, don't go too low because some circuits will oscillate
badly. The safest thing to do is check the existing caps of your monitor
and go to their manufactures' websites to find their characteristics and
get caps that match...or buy a capacitor kit specifically for your monitor from a reputable parts supplier. :)
 
G

Gabriel Knight

Hay Paul I got you some pictures of the (video?) baord and the surface mount
crystal I will very soon remove the crystal to see if the sound is coming
from inside the crystal. I will aslo buy a capacitor tester befor I get a
capacitor kit and test them one by one after I have removed them from the
board. If you need any better shots I will borrow my friends camera as mine
is a 10 mega pixel and his is about 16 mega pixel. Could this crystal if
faulty be the component to cause the long time on and then the two second
delay to auto off and not the caps like many people were saying though on
the power board? They all said it was the power baord and caps and that this
was a very common problem with the 2493HM construction. Regards GK.

http://s836.beta.photobucket.com/user/sierragames/library/Samsung 2493HM PCB with ballbearing sound
 
P

Paul

Gabriel said:
Hay Paul I got you some pictures of the (video?) baord and the surface mount
crystal I will very soon remove the crystal to see if the sound is coming
from inside the crystal. I will aslo buy a capacitor tester befor I get a
capacitor kit and test them one by one after I have removed them from the
board. If you need any better shots I will borrow my friends camera as mine
is a 10 mega pixel and his is about 16 mega pixel. Could this crystal if
faulty be the component to cause the long time on and then the two second
delay to auto off and not the caps like many people were saying though on
the power board? They all said it was the power baord and caps and that this
was a very common problem with the 2493HM construction. Regards GK.

http://s836.beta.photobucket.com/user/sierragames/library/Samsung 2493HM PCB with ballbearing sound
Other than the crystal, another idea that comes to mind, is perhaps
the monitor has portrait-landscape capability ? Perhaps there is a
component on the board which senses monitor orientation, and switches
between portrait and landscape ? You'd think they could do that
with a mercury switch (which would be silent), but a ball bearing
in a precious metal plated base, might also be used.

I see a black thing, just below the chip with the heatsink (probably
a memory). It has four leads on it. I don't think it's a transformer,
but I could be wrong.

The main chip is made by mstarsemi.com but they don't offer any
datasheets. Apparently that company was just bought by MediaTek.
To support my portrait-landscape theory, I'd be looking for
a pin on it that senses such things.

Paul
 
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L

larrymoencurly

I will aslo buy a capacitor tester before I get a
capacitor kit and test them one by one after I have
removed them from the board.
I hope you mean an ESR meter and not a capacitance meter
because I've found that lots of caps will measure OK for
capacitance but are bad because their ESR is sky-high.
However an ESR meter is more expensive than a capacitor
kit.

I would also resolder the circuit board because sometimes
a microscopic solder crack can delay turn-on until a
component heats up moves enough to close the solder crack.
Typically it's not necessary to resolder every joint, only
those around high power components, heavy components, and
places of mechanical stress, like connector pins.
 
G

GMAN

I hope you mean an ESR meter and not a capacitance meter
because I've found that lots of caps will measure OK for
capacitance but are bad because their ESR is sky-high.
However an ESR meter is more expensive than a capacitor
kit.

I would also resolder the circuit board because sometimes
a microscopic solder crack can delay turn-on until a
component heats up moves enough to close the solder crack.
Typically it's not necessary to resolder every joint, only
those around high power components, heavy components, and
places of mechanical stress, like connector pins.
Also, when my 24" Acer monitor went out, it wasnt the control board that went
out, but the 8 capacitors that controlled the backlights along the edges of
the monitor.
 
G

Gabriel Knight

Hi Paul I found a service manual and put it on a file sharing site it is
only there for 7 days here:

http://wikisend.com/download/864364/Troubleshooting.pdf

on page 7 (4-7) there is mention of the crystal called "X300" with page 8
showing its value of 14.31818MHZ it is spot on for the crystal I have at
14.318180MHZ but the second digits under the 14.31818MHZ on the PDF have
"HC-49/S-SMD" mine is different as it has "KONY 0832" I dont think it has a
sensor for the tilt portrait/landscape but If im to replace this crystal
where do I get one? Thank you, GK.
 
G

Gabriel Knight

I removed the component that was making the sound it is not the crystal but
on the schematic diagram uploaded here:

http://wikisend.com/download/779270/Schematic Diagram.pdf

on page 4 (7-4) there is a red boader around the main "IC300" and on the top
righ of the boarder is a component called "S301" this is the part with the
sound, what is this thing?

the part has no numbers or id but it has a "D" on top and thats it. Where
can I get a replacement for this part? Thanks all, GK.
 
G

Gabriel Knight

I found a data sheet for this part and it IS a tilt sensor found here:

http://datasheet.octopart.com/SPSF100100-ALPS-datasheet-57855.pdf

now that I have removed it is there a way to link the four contacts on the
PCB so I dont have to resolder it back on as the data sheet says to use hot
air heating to put it on thats something I dont have unless its safe to use
a soldering iron I will put it back if its safe to use a soldering iron or I
will have to find an electronics tech. in a store to help me. GK.
 
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R

Rene Lamontagne

I'm not familiar with that Ebay dealer, but it may help if you can
get pictures of their capacitors and compare them to the illustrations
given here:

http://capacitor.web.fc2.com/

Each electrolytic capacitor has a pattern stamped on top, to let it
explode more safely (really), and that pattern may help identify
fakes, emphasis on "may". For example, DealExtreme.com has
sometimes offered Sanyos, which are normally stamped with a "K" or
funny cross that looks like "><", but DealExtreme's were stamped
with 3 equal pie slices with a dot in the middle of each slice
(Teapo, an inferior brand) or with an ordinary "X" or "+" (probably
the most common stamping pattern, used even by some good caps).
There was one Ebay dealer that sold counterfeits with new heatshrink
plastic over them and over the original heatshrink.

You want choice "b", the aluminum capacitors. Places like Digi-Key and
Mouser let you specify about 10 different parameters, but it's best to
specify just the capacitance and voltage because their online catalogs
don't let you specify the maximum temperature without also specifying
the minimum temperature or the diameter without also giving the height.
I don't understand why modern computerized catalogs are so much slower
to use, compared to paper catalogs. And while low ESR and impedance are generally good, don't go too low because some circuits will oscillate
badly. The safest thing to do is check the existing caps of your monitor
and go to their manufactures' websites to find their characteristics and
get caps that match...or buy a capacitor kit specifically for your monitor from a reputable parts supplier. :)
Hi Gabriel, Sorry to catch this thread so late. Paul is correct in his
assumption that this monitor can be landscape or portrait, Yes this is a
rotational monitor and it can sense is orientation.

In electronics diagrams Switches are usually denoted with the letter S,
as in S301, so I think your clicking part is an orientation sensing
switch and may not be faulty.
Did the monitor work in Both positions before removing the switch?
It looks like it could be a DPST unit where it makes 2 contacts in one
position and the 2 other contacts in the 90 deg position, if the switch
is OK you can check this with an ohmmeter. if the above proves true you
could jumper the 2 landscape pads together on the motherboard and use it
in that position only. the other 2 pads would remain disconnected.

Hope this helps a little with your problem.

Good luck and A Happy New Year, Rene
 
P

Paul

Gabriel said:
I found a data sheet for this part and it IS a tilt sensor found here:

http://datasheet.octopart.com/SPSF100100-ALPS-datasheet-57855.pdf

now that I have removed it is there a way to link the four contacts on the
PCB so I dont have to resolder it back on as the data sheet says to use hot
air heating to put it on thats something I dont have unless its safe to use
a soldering iron I will put it back if its safe to use a soldering iron or I
will have to find an electronics tech. in a store to help me. GK.
Compare the soldering profile, to other components and their soldering profile.
Unless there is a limit to the number of cycles the thing can sustain,
you might be able to get away with putting it back. Try using your lower
power iron. For example, if I used my 80W iron, there'd be no way for
me to touch it fast enough, to prevent a temperature overshoot. I'd probably
try my 15 watt iron.

You could tin the board with ChipQuik or other low temperature solder,
and reapply the sensor that way.

Did you manage to find an application note for it ? Nothing popped up
in my search engine.

So going on intuition, it could consist of a circular race track, inside
a top half and bottom half plastic section. The top half, has two 180 degree
gold plated contact areas. The bottom half has two 180 degree gold plated contact
areas, but they're rotated 90 degrees to the top half. As the ball rotates in
the race track, it touches one top half and one bottom half contact. As the
ball rotates around the compass points, it closes the contact in the
1-2, 2-3, 3-4, 4-1 sequence. What I couldn't figure out, is the "cheapest"
way of using it as a sensor. The contacts are likely "noisy", so as the
ball moves around the racetrack, the pins could be momentarily all open
circuit, until the ball again touches a top and a bottom gold contact.
Max current flow is 1 milliamp, likely intended to prevent the ball
from "welding" to the rings.

Maybe a criss-cross ? Connect contacts 1 and 4. Connect contacts 2 and 3.
That makes an SPST switch, which is closed in horizontal orientation
or when rotated 180 degrees (still horizontal but upside-down). That
makes an active low logic signal to some chip, whenever the panel is
horizonal. If the panel is vertical, the signal goes high, whether
vertical right-side-up or vertical upside-down. I suppose a "deluxe"
product would display data correctly in any orientation, in which case
you'd end up wiring the contacts independently. A hint as to intention,
would be the design of the support for the panel. Whether it only
has a 90 degree rotation in a preferred direction supported or not.
If the panel supports free rotation with respect to the base,
maybe the panel even reverses the data when rotated 180 degrees. To
support perfectly free rotation, wiring like this wouldn't work right.

+5V
|
Pullup 10K
|
+-------+-------+-----------> HORIZONTAL#
| |
Pin1 Pin4

Pin2 Pin3
| |
+-------+-------+
|
Gnd

Wiring it as I've shown there, would only support two compass points,
and not support reversing the order of pixel presentation.

If the tracks to it are on the top layers of the PCB, perhaps you can
check for the joining of the pins. That would indicate intent.

If it is a crisscross, wire a switch in its place. Turn on the monitor
with the switch open. Check "sanity" of display. If not correct,
flip the switch to the clsoed position. Note - the switch idea is only
reasonable if you find the specific crisscross style solution. If the
panel supports perfectly free rotation, you'll need four switches,
to emulate 1-2, 2-3, 3-4, or 4-1 contact closures.

Paul
 
G

Gabriel Knight

Thanks very much Rene I tested the switch (S301) with an ohmmeter it still
works in all 4 directions so I will put it back on the board and continue to
buy a caps kit. In the troubleshooting pdf on page 7 :

http://wikisend.com/download/864364/Troubleshooting.pdf

it mentions the crystal as a possable fault and to check if it is
oscillating normally how does one check this? If I buy a capacitor tester do
I really need to by an ESR as well as these are worth more than the monitor
and time I have to get one.

I will post a picture of the contacts very soon and the board direction when
its in the horizontal position to make sure im bridging the two contact
correctly, I am getting rid of the switch till I replace the caps as I had
to use a bit of heat with solder wick to remove the switch and it might not
be working at 100% as the data sheet said "use hot air to solder". I know is
elementry for how the switch works but I ask to make sure. Thanks, GK.
 
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P

Paul

Gabriel said:
I removed the component that was making the sound it is not the crystal but
on the schematic diagram uploaded here:

http://wikisend.com/download/779270/Schematic Diagram.pdf

on page 4 (7-4) there is a red boader around the main "IC300" and on the top
righ of the boarder is a component called "S301" this is the part with the
sound, what is this thing?

the part has no numbers or id but it has a "D" on top and thats it. Where
can I get a replacement for this part? Thanks all, GK.
OK, I had a look at the pullup-pulldown pattern around the SPSF100100
and now I'm even more confused :) There are four "pivot" signals
coming from the thing, implying it reverses display order in a
couple of the orientations. Pretty fancy.

If you wanted to emulate the device, you'd simply wire together a specific
pair of terminals. If the device supports 1-2, 2-3, 3-4, 4-1 as
contact closures, you'd select one of those and say, wire 1 to 2 to make
the first one without the sensor in place. If the display didn't look right,
wire 2 to 3 and try again. Or, grab a four position DIP switch, run wires into
the display, and close one of the four DIP switch positions, to select
one of the 1-2, 2-3, 3-4, 4-1 possibilities. Since those signals would be
ESD sensitive, you wouldn't want to allow too much handling of the wiring.
I notice the design makes extensive use of clamps for ESD protection.

*******

IC300 has the 14.318180MHZ crystal, a two lead device with "non-logic"
levels. It's an analog component, part of the oscillator on the logic
chip. It establishes the digital clock the chip uses. It could be
multiplied up inside the chip with a PLL, so in fact the chip could
be running at a much higher frequency than that. Crystals like that
are selected for least cost.

The 14.318 value is mentioned here, and is used for TV colorburst.
If half a billion TVs use such a crystal, the crystal ends up being
dirt cheap, and suitable for building half a billion more computer
monitors.

http://en.wikipedia.org/wiki/Colorburst

Using a PLL and multiplication techniques, they could operate at
16 times that frequency if they wanted. Or, whatever.
 

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