Oh, I forgot to post this... only sent it to John.
----- Original Message ----- From: "Stephan Hachinger" <[EMAIL PROTECTED]> To: "John Pearson" <[EMAIL PROTECTED]> Sent: Wednesday, August 02, 2000 12:49 PM Subject: Re: noise from monitor, HELP! > Hello! > > > > > Now all of a > > > sudden I get a VERY high pitched noise from it when in X. It does not do > > > this on the console! It has become more and more frequent and is > > > starting to drive me nuts (well more then usual :) I know it's the > > > monitor because I can turn it off while it's doing it and the noise > > > stops. Does anyone know what the problem might be? > > > > > > > If it is a regular CRT-style monitor, there are wire coils > > wrapped around the CRT to deflect the electron beam to provide > > horizontal & vertical deflection; these are probably glued in > > place (or at least, in bundles) using epoxy resin or something > > similar. > > > > Probably, the epoxy has cracked or come loose from whatever it's > > anchored to at some point and what you can hear is some or all > > of the windings on the horizontal deflection coil rattling back > > and forth in time to the horizontal scan, in accordance with > > Newton's laws ("For every action there is an equal and opposite > > reaction"). Just maybe, it's some other part of your monitor's > > yoke doing the same thing. It's irritating as hell if you can > > hear it, but it shouldn't affect the monitor's performance or > > reliability. > > John is right! It's probably one of the wire coils, as I just read on a > German homepage. > > Andrew wrote: > > I usually just hit mine :) > He's wrong, I think. Hitting electronic components indeed stops many > problems, but in this case, the deflection coils get even more loose and so > it's just a temporary solution. > > > > Possible solutions: > > - Pay someone to fix it. If you take it in for a service, be > > *very*clear* about the problem or it probably won't get fixed > > (chances are, most of their techs won't be able to hear it). > This is the only one I suggest! > > Or perhaps, at a lower or higher vertical frequency, the noise does not > appear any more. > > You can also try to fix the coils yourself. But be aware of HIGH VOLTAGES > appearing in monitors even if they are plugged off. There are capacitors > installed. So, if you wanna fix them, put on rubber gloves. And start the > repair after you have plugged it off for some hours. Don't touch any metal > parts if possible, because there are maybe still parts carrying high > voltage. > > To repair it, simply open the case, locate the coils and fix them using > epoxy 2-component glue. > > If the problem does not disappear after this action, maybe it wasn't caused > by the deflection coils but by the "line transformer" (this is how Germans > call it, I don't know if this is good English). I've read that this > transformer can be located by backtracing the thick anode cable starting at > the picure tube. The site said you can fix the parts of this transformer > using "plastic spray". Does anyone know if epoxy also works? I think so. > > *IMPROTANT* If you open the monitor case, the granted guarantee period is > definitely aborted and over. And I have once opened a monitor using thick > rubber gloves, but never done the above to any. So I do not know what the > result will be. If you don't know about electronics, you should better have > it fixed by anyone else instead of lying kind of "ESD-demaged" besides your > monitor and not moving any more. But it is very likely that fixing the > deflection coils will fix the problem for the next years. About the plastic > spray: I do not know what it is and if it works and what happens if you > don't spray it only on your trafo but also on the rest of the electrics by > accident. I've only read about it. > > > Regards, > > Stephan Hachinger >