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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Philski on January 19, 2010, 04:14:08 PM
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Hi there,
I just picked up one of these monitors from eBay and just had a question about it.
Is it usual for these monitors to make a crackling sound (a little like static) or is it defective?
Regards,
Phil
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Powering up and/or down, sure, that's normal. While it's running, generally no.
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Thanks for the reply!
Hmm, I'll leave it on for a bit and see how it goes - it might just be through lack of use.
P.S. Is there a knack to getting the power button to work?
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Pop it open and blow out all the dust. Take a slightly damp rag and clean off the accumulated crap on the back of the tube where the wires harness it. Keep one hand in your back pocket when you're working on the thing.
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Thanks for the tip! :)
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Pop it open and blow out all the dust. Take a slightly damp rag and clean off the accumulated crap on the back of the tube where the wires harness it. Keep one hand in your back pocket when you're working on the thing.
LOL! Are you sure you didn't mean to say 'front pocket'? lol Umm... to the original poster, the advice above is a surefire way of getting zapped! lol
If you're going to be taking a damp anything near the back of the electron tube, you'd better be sure you discharged it first. Easy to do and will save you the risk of potential shock. Personally, I'd just take a can of air spray, or better yet, take a vacuum cleaner hose w/ brush attachment to the guts of the monitor to get up any dust, webs, etc. Those cans of air just end up making a mess out of your house and eventually back into whatever you were "cleaning", but people still buy the things.
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pop it open and blow out all the dust. Take a slightly damp rag and clean off the accumulated crap on the back of the tube where the wires harness it. Keep one hand in your back pocket when you're working on the thing.
noooooo!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
do not do this unless you are an experienced technician!! There is potentially lethal voltage at the back of the tube!!!
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Thanks for the safety tips!
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Holy crap Red! IF he didn't get the idea from my response, he'll surely see this one!!!! lol
To the OP, if you want to discharge your tube and eliminate the risk of getting fried - get yourself a long/thin flat blade screwdriver and a jumper wire with alligator clips on each end. Secure one end of the jumper wire to the chassis (ground) of the monitor and the other to the conductive part of your screwdriver. You of course, are only gripping the handle of the screwdriver at this point (common sense eludes us sometimes)... Next, (and with the monitor off of course), find the suction cup attached to the tube which usually has a thick red wire coming from it and going to the HV section of the chassis. With the alligator leads connected like I said, sneak the screwdriver underneath the suction cup toward the middle and wait for a loud (or soft sometimes) cracking/snapping/popping sound. Repeat until you hear nothing. There... that's all there is to discharging a picture tube. Don't be a careless monkey about it and you'll be fine.
Oh and the power switch on these models do tend to get sticky, making it difficult to easily turn on and off. I usually (and very carefully) just spray a tiny amount of WD-40 on each side of the switch (facing the front of the monitor) and wipe any excess off with a rag.
NEVER, EVER use WD-40 near circuit boards however. That's what contact cleaner is for.
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I had to take my power switch out and solder the wires together to keep it on. The power connects to the back of the Amiga anyway, so it's quite handy.
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LOL! Are you sure you didn't mean to say 'front pocket'? lol Umm... to the original poster, the advice above is a surefire way of getting zapped! lol
If you're going to be taking a damp anything near the back of the electron tube, you'd better be sure you discharged it first. Easy to do and will save you the risk of potential shock. Personally, I'd just take a can of air spray, or better yet, take a vacuum cleaner hose w/ brush attachment to the guts of the monitor to get up any dust, webs, etc. Those cans of air just end up making a mess out of your house and eventually back into whatever you were "cleaning", but people still buy the things.
The popping is caused by one of two issues. One is a break down of the dielectric material in the flyback, the other is poor contact with the back of the tube (the conductive paint on the glass) and the grounding harness. You can spray air all you like on a decade old + tube and it won't make a better ground path.
Yea, I get your joke about the front pocket thing. Huhuhuhuhuh "pocket pool". The point of the "pocket rule" is that you don't make a circuit from one hand to the other thus zapping your heart. I don't think anybody ever got killed from a finger to finger zap.
Yea, working on monitors can be dangerous. If you're uncomfortable with it, or don't have a clue about electronics then by all means, stay away from it. Else, proceed and keep your gear up and repaired. Working with old, classic equipment means you spend a lot of time fixing your gear.
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Holy crap Red! IF he didn't get the idea from my response, he'll surely see this one!!!! lol
To the OP, if you want to discharge your tube and eliminate the risk of getting fried - get yourself a long/thin flat blade screwdriver and a jumper wire with alligator clips on each end. Secure one end of the jumper wire to the chassis (ground) of the monitor and the other to the conductive part of your screwdriver. You of course, are only gripping the handle of the screwdriver at this point (common sense eludes us sometimes)... Next, (and with the monitor off of course), find the suction cup attached to the tube which usually has a thick red wire coming from it and going to the HV section of the chassis. With the alligator leads connected like I said, sneak the screwdriver underneath the suction cup toward the middle and wait for a loud (or soft sometimes) cracking/snapping/popping sound. Repeat until you hear nothing. There... that's all there is to discharging a picture tube. Don't be a careless monkey about it and you'll be fine.
Wow, the grand master of electronics advocates shorting parts to ground with a screwdriver. :roflmao: Yea, folks do it, but it's not something to brag about. Most folks don't screw with alligator clips discharging a tube. Just one screwdriver under the suction cup and another screwdriver pushed against it to the conductive paint on the glass. Not that any of this crap matters since I doubt the original poster is interested in extricating his tube.
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noooooo!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
do not do this unless you are an experienced technician!! There is potentially lethal voltage at the back of the tube!!!
even when disconnected!!!!!
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Wow, the grand master of electronics advocates shorting parts to ground with a screwdriver. :roflmao: Yea, folks do it, but it's not something to brag about. Most folks don't screw with alligator clips discharging a tube. Just one screwdriver under the suction cup and another screwdriver pushed against it to the conductive paint on the glass. Not that any of this crap matters since I doubt the original poster is interested in extricating his tube.
??
Handling two screwdrivers is less safe than one with a jumper lead (duh) and besides, in the arcade world where people work on monitors all day long (I work on at least a couple of monitors a week), that's the quickest and easiest way to discharge a tube. Nothing wrong with that practice and I don't see why anyone would "need" to brag about it or post your "grandmaster" comment either. It is what it is. You guys are making a mountain out of a mole hill. Especially the dude that copied Red's GIGANTIC warning... lol
Recommending that the OP take a damp cloth to the back of the picture tube was silly at best (if it was meant to be serious that is) and dangerous at worst. I provided a simple step by step outline that would curb the liability of shock was all.
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Do you have a better suggestion for cleaning the muck off the back of the conductive paint on the tube which frequently leads to popping on old monitors because it interferes with the ground path through the wiring harness? Yea, I was a monitor repair guy too back in the day.
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Do you have a better suggestion for cleaning the muck off the back of the conductive paint on the tube which frequently leads to popping on old monitors because it interferes with the ground path through the wiring harness? Yea, I was a monitor repair guy too back in the day.
Your method was fine (damp cloth), but you forgot to mention that the tube needed to be discharged first, which caused me to laugh out loud when I read it :P Personally, I vacuum the surrounding area first (it's usually coated in black fuzz) and then spray contact cleaner on a cloth to tack that crap up.
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Your method was fine (damp cloth), but you forgot to mention that the tube needed to be discharged first, which caused me to laugh out loud when I read it :P Personally, I vacuum the surrounding area first (it's usually coated in black fuzz) and then spray contact cleaner on a cloth to tack that crap up.
Yes, I should have mentioned to discharge the tube. Probably shouldn't have even posted, but part of me wants to help out.
Contact cleaner is probably a good idea though I never used it because I've seen contact cleaner degrade some kinds of plastic, probably would have helped a lot when working on sets folks have smoked around. All that greasy crap from cigarettes coats everything and the dust has a party in it.
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Contact cleaner is probably a good idea though I never used it because I've seen contact cleaner degrade some kinds of plastic, probably would have helped a lot when working on sets folks have smoked around. All that greasy crap from cigarettes coats everything and the dust has a party in it.
The thing about using contact or "tuner" cleaner is that it acts as both a degreaser and a cleanser, but also dissipates rather easily. Great stuff. Never ate away anything that didn't belong from my experience anyway.
And very true about cigarette smoke. If anyone ever has any doubts as to the damage it causes to the human body - try looking inside of certain electronics like picture tubes or even CD laser assemblies. That shit literally cakes and coats everything and attracts dust and even more tar and crap as time goes on. RARE is the classic arcade machine NOT completely coated in the stuff.
Similarly, did you know that the fumes of Kerosene literally eat away wiring and circuit board traces? That's some pretty potent stuff. And yeah, it's hardly used anymore to heat peoples homes, garages, or whatever - but back in the 70's and 80's, I knew a few families that had those things running as their main source of heat. My dad even tried it for a short stint in his stubborn refusal to get the old oil radiators repaired, so I've seen first hand the damage those fumes can cause. Yuck!
BTW: nothing wrong with giving advice, just have to remember to warn about the perils of this sort of thing. lol I like to chime in once in a while about hardware dealings because I'm not so good with the software side of it. Countless people here have helped me with configuration or software probs, so I figure if I can help out in anyway with hardware - that some of the Karma and gratitude gets paid back. :)
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Contact cleaner is probably a good idea though I never used it because I've seen contact cleaner degrade some kinds of plastic, probably would have helped a lot when working on sets folks have smoked around. All that greasy crap from cigarettes coats everything and the dust has a party in it.
Helping out is a good thing. IMHO you just have to be careful with advice on forums. There is a long history in the Amiga community of people with no electronics experience misunderstanding advice and toasting expensive hardware, so my first fear was someone putting a wet rag to an energized tube.
Us oldtimers remember thinsg like an AmigaOne user prying SMD chips off his board with a screw driver, or something along those lines. Voiding his warranty and toasting the $1000 board.
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Thanks for the suggestions everyone!
At the moment I'll probably leave things as they are as after the first ten minutes or so of use it hasn't repeated, however if it does need a bit of a service I have plenty of info to go on here :)
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Glad to be of service! Oh yeah... one last bit of advice: don't fry bacon in the nude! :lol:
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Glad to be of service! Oh yeah... one last bit of advice: don't fry bacon in the nude! :lol:
And never laminate whilst wearing a tie.
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Hi Guys,
To anyone living in the Norwich area, there's a working 1084 Monitor going FREE!
Tim.