[Coco] Can I fix an old monitor?

[Dave Philipsen]

Sounds like a power supply problem that is possibly tied to the backlight. Some of these older monitors used a CCFL (cold cathode fluorescent lamp) for the backlight. I’d look for bad caps, as suggested. 

-Dave Philipsen

> On Apr 27, 2020, at 10:26 AM, Walter Zambotti <zambotti at iinet.net.au> wrote:
> 
> The symptom it displays is a little odd.
> 
> It has trouble turning on and trouble coming back out of sleep mode.
> 
> I can use it for hours and hours but go away for twenty minutes and
> it wont redisplay.  I can see it is trying because I get some screen
> flashing.
> 
> And sometimes after several flashes it might come back on.
> 
> But once it's on its stays on until I stop using it a let it sleep.
> 
> Walter
> 
>> On 2020-04-27 23:09, Arthur Flexser wrote:
>> Two things that come to mind:
>> 
>> First, look for capacitors that are swollen or leaky.  Though I don't know
>> that the symptom there would be dying after a few minutes rather than just
>> not working at all.
>> 
>> The dying after a few minutes sounds more characteristic of a chip
>> overheating.  Carefully feel if any chip has gotten very hot after the
>> thing dies.  (Be careful to avoid high voltages!)  That chip would be a
>> prime suspect.  You might time how long it takes for the thing to die after
>> you turn it on, and see if holding an ice cube in a plastic bag against the
>> suspect chip lengthens this time significantly.
>> 
>> Good luck!
>> 
>> Art
>> 
>> On Mon, Apr 27, 2020 at 10:55 AM Walter Zambotti <zambotti at iinet.net.au>
>> wrote:
>> 
>>> I have an old 4x3 1280x1024 LCD monitor that is still working but is
>>> loses picture when it has been on for a few hours. It's an ACER AL1916 A.
>>> 
>>> I would like to repair the thing to use with my CoCo but I have no
>>> hardware experience with these things.
>>> 
>>> How hard is it to diagnose what the problem is?
>>> 
>>> And what are my chances of fixing it?
>>> 
>>> Walter
>>> 
>>> 
>>> 
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> 
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