killed 2 monitors in 2 weeks...

[alexh]

A1260 wrote:
that HighRes Interlaced, 50 Hz / 15 kHz screen mode. Is one "unhealthy" mother thats for sure, you should not use it on old monitors...

Another great reasoned, technical answer from the master.

[McVenco]

A1260 wrote:

that HighRes Interlaced, 50 Hz / 15 kHz screen mode. Is one "unhealthy" mother thats for sure, you should not use it on old monitors...

The only 'unhealthy' thing about Interlaced screenmodes is that it's impossible to look at for longer than 10 seconds without getting some sort of pain behind your eyes. It doesn't do any more harm to the monitor than other screenmodes.

The best thing to do to save your old monitors is not using them. :-)

[pulppure]

I'm an old amigan and I saw that some of you have the schematics for the Philips CM8833-II (1083s like) can you PM me please ?

I haven't found them on the web (only the ones for the Commodore and I'm not even sure they are the right ones as there were different models of the 1083s)

So this monitor went dead a month ago, now the only thing it does is a black screen and whistling noise, which makes nice fading modulations when I turn it off... you can listen to it here :

http://pulppure.free.fr/amiga/moniteur.wav

Do you have an idea of what I should replace first : flyback transformer, capacitors, transistors ? How to diagnostic ?

[CLS2086]

Hi,
change the flyback transformer and the transistors, and if you can also change the diodes.
It's quite cheap in France.
flyback transformer HR7533 (for 1084S-P1 and lot of others made by philips) : 22 euros

[AmigaMance]

alexh wrote:

A1260 wrote:
that HighRes Interlaced, 50 Hz / 15 kHz screen mode. Is one "unhealthy" mother thats for sure, you should not use it on old monitors...

Another great reasoned, technical answer from the master.

:-D

[Tomas]

Give it a light smack and see if that does anything  :-P
If it does, then it is most likely just some bad solder joint somewhere.

[taunusand]

Tomas wrote:
Give it a light smack and see if that does anything  :-P
If it does, then it is most likely just some bad solder joint somewhere.

I agree :-)

My CM8833 had EXACTLY this problem, after I soldered the transformer the problem was solved.

[A1260]

by alexh on 2007/12/19 3:35:39


Another great reasoned, technical answer from the master.

thanks and that answer was a joke, but some must take everything seriously i guess...  :lol:

[Plaz]

I also guess it's that transformer (whistling noise).

Common "whistlers" are large caps gone bad. I don't recall from memory if that model has a bi-polar cap or not. If so, it's the first one to replace. It will be sort of large, near the flyback, and labled some thing like 4.7UF 160V BP. If you haven't blown a fuse then the flyback is likely still good. There is also a lage transistor near the flyback attached to a heatsink. Make sure the legs of that transistor are well soldered too. It's difficult (and dangerous) to try and talk someone through a monitor repair. If you're not experienced, then it's probably best to take it to a good repair shop.

Why might you pay attention to all of the above? I have 3000+ repairs of video displays of every type, model and manufacture over my career. :-P

Plaz

[da9000]

I fully endorse what Plaz wrote, word for word, except his last paragraph :-) I'm no expert like him, but whistling or whizzing noises are very often big ol' caps from my personal experience.

And be careful!

@alexh:
 :hammer:

[rkauer]

 ...or a broked insulation of the flyback.

[AMC258]

Or a bad horizontal sweep oscillator output.  But, that would be extremely rare.  That is usually only the case if it's an all-tube TV.

[circlip]

Man, I used to have an old commodore 64 monitor (can't remember model.) It died a year ago, I was sad. I pretty much used it for everything, DVD, playstation, video recorder, etc.

I now own a very crappy tv for all of the above plugged into it, and my A500 has an old "green screen" as you can see. VERY retro!

[da9000]

@rkaur:

From my experience the flyback will more likely cause snapping sounds as it arcs. Or sound distinctly different.

circlip wrote:
I now own a very crappy tv for all of the above plugged into it, and my A500 has an old "green screen" as you can see. VERY retro!

AHAHAHAHAHA! VERY retro indeed :-)

But Circlip, there's not excuse for not getting another C= monitor. There are plenty around still. I myself only have about a dozen! Too bad you're down under... I'd sell ya one if you were closer!

[rkauer]

da9000 wrote:
@rkaur:

From my experience the flyback will more likely cause snapping sounds as it arcs. Or sound distinctly different.

 Your comments are right, but my name is Kauer, Rogério Kauer...

[da9000]

My sincerest apologies Rogério! The spellchecker doesn't know you by name I guess!!! :-)