Thus begins my first thread on the new forum...:D

So I rescued a model year 2000 55" Philips Magnavox rear-projection television set two nights ago, fully five minutes before the trash truck came rolling by. I couldn't bear to see the TV suffer the same fate as the nearby range, you know me. :D

So I get the beast situated outside the garage the next day. I plug it in and immediately get HV whine and sound. However, as soon as the screen is bright enough to see, I am horrified to see the infamous fuzzy picture associated with bacterial growth in the CRT cooling fluid in these sets. :dammit: Off goes the back cover.

Being relatively inexperienced with how to actually deal with this problem, I proceed to remove the lens from the blue CRT (it was surprisingly the only one with growth in the fluid), not realizing that the same screws that hold the lens on also secure the fluid tank seal. Cooling fluid goes everywhere, including all over the mainboard. :gigglemad Realizing my grave error, I immediately replace the seal and lens, then set about using the nearby leaf blower to banish the fluid from the circuitry. I hope I got most of it off, as I have been told that it will not evaporate.

So after waiting about ten minutes, I plug the set back in and try it. Sound, but no picture at all. :bs: I can hear the HV but there are no CRT filaments burning. Five minutes later I get faint wisps of white smoke coming from somewhere over the mainboard, so I freak out and unplug the set again. So now I have a 30 percent loss of cooling fluid in one CRT AND no picture. Worse than what I started with! :finger: Is there hope, or should I just part out the set and get it over with? :thumbsdn:

Another thing: The cooling fluid (Glycerol, apparently) is nowhere to be found. I was able to locate exactly one supplier online that had it, and they had discontinued it and were out of stock. I have been told that the process of replacing the cooling fluid is long and tedious, but as I need only replace one CRT's worth, I might try. Help! :banana:

000

If you have waited any length of time to clean the boards that were spliied on you will experience repeated failures as the glycol is very(!) corrosive. It will eat the board up slowly. We don't take them in any more because it is a sure comeback once the corrosion starts.:thumbsdn:

Thanks for the info, guys. I really hope it's not too late for me to remove the Glycerol! (it's been about two days now) Also, andy, would one bottle be adequate, and will I need any special tools to inject the new fluid?

P.S.--You mention removing the old fluid by using water. Should I be careful, or do you recommend a special way to do this? I mean, I shouldn't be just removing the board and spraying it with the hose, should I? :eek:

000

Good learning experience here. It's be a miracle if you get it going again. Keep us posted!

Good learning experience here. It's be a miracle if you get it going again. Keep us posted!

I was dreading that phrase. :D Well, it's DUMPING rain here right now, so there's no way I can get into the set now. (don't worry, it's covered!) I really hope I can get it working again...:))

we use windex and water it works 100% of the time in getting coolant off. then use a heat gun or hair dryer on the board.........

we use windex and water it works 100% of the time in getting coolant off. then use a heat gun or hair dryer on the board.........

Just spray the board down with Windex, let it sit for a few seconds, and hit it with the water?

I removed the board today and sprayed the entire thing down with the 'mist' setting on my garden hose. I covered the openings on the flyback and HV distributor so as not to let moisture in. Then I used a combination of a hair dryer and leaf blower to dry the board thoroughly(hair dryer wasn't moving enough air!). Thank God they numbered all of those zillions of wires connecting to the board, by the way. :D

So it's all back together. Now I try it again. When I hit the power button for the first time, the flyback (I think) makes a buzzing like a bug stuck in a zapper, so I unplug the set. I also notice a good amount of smoke coming from behind a side panel that I can't tell what's on the other side of. I remove said panel and thankfully can't find anything charred or smelly. So I try it again. (bad idea?) This time I hear a low-pitched whine for about a second, then the flyback tries to start up but cuts off within a quarter second. No smoke at all this time. I try this several more times always with the same result. My guess is that there is some moisture inside the flyback that is causing a short, which in turn is causing the power supply to shut itself off to prevent damage. Do you think that if I give it some time, the moisture in the flyback will evaporate and I might get better results?

I know that others have said that using water on electronic circuitry is not harmful, but I would never have done that on purpose - there are circuit board cleaning and degreasing sprays that are non-conductive and they evaporate very quickly so that they can be sprayed on live powered circuitry with no danger or damage at all. Since you did use water, it would have been a good idea to let them dry completely for a few days before trying to power them up.

Unfortunately, you let the smoke out of at least 1 or more components - and even though nothing looks burnt, they are damaged and will no longer work properly, or even within critical safety specifications. On all manufacturer service documentation, and even third party service manuals, critical safety components are usually identified as such with at least an exclamation point symbol.

If you do attempt to continue troubleshooting this set, PLEASE proceed with extreme caution from this point on.

I know that others have said that using water on electronic circuitry is not harmful, but I would never have done that on purpose - there are circuit board cleaning and degreasing sprays that are non-conductive and they evaporate very quickly so that they can be sprayed on live powered circuitry with no danger or damage at all. Since you did use water, it would have been a good idea to let them dry completely for a few days before trying to power them up.

Unfortunately, you let the smoke out of at least 1 or more components - and even though nothing looks burnt, they are damaged and will no longer work properly, or even within critical safety specifications. On all manufacturer service documentation, and even third party service manuals, critical safety components are usually identified as such with at least an exclamation point symbol.

If you do attempt to continue troubleshooting this set, PLEASE proceed with extreme caution from this point on.

This is not encouraging. I needed to use water because the coolant was everywhere, and probably would have been near impossible to completely remove otherwise. I'm not sure where the smoke came from, but I will take a closer look tomorrow. It seemed to emanate from the general vicinity of the audio amplifier. Hopefully, it's something simple(capacitor, resistor, etc.).

Does anyone know of a place where I might find schematics for this set? :scratch2:

P.S.--Is that a CRT from a video camcorder viewfinder in your avatar? :D

The MSDS for the replacement coolant says that it is about 75% ethylene glycol and 25% glycerine. I'm not sure there's much besides water that would have worked.

While letting it dry longer might have been prudent, any damage done probably occurred when you turned the set on right after the leak.

You could try partsrruss.com for the service info or use google with the the model number and "service manual" as the keywords.

John

000

The MSDS for the replacement coolant says that it is about 75% ethylene glycol and 25% glycerine. I'm not sure there's much besides water that would have worked.

While letting it dry longer might have been prudent, any damage done probably occurred when you turned the set on right after the leak.

You could try partsrruss.com for the service info or use Google with the the model number and "service manual" as the keywords.

John
I guess I should have stated the little detail that the set was up and running when the spill occurred. FWIW, nothing wrong AT ALL happened until I turned the set OFF. :D

andy, I'm still hoping that if I let it dry for a few more days, I'll get somewhere. If not, it's looking more and more like the scrap heap for this set. :sigh:

If you're lucky, the smoke came from a wet power resister, or another component that normally operates hot. I wash stuff regular with heavily-deluted dish soap, or Windex, but it has to be bone-dry before power is applied. I had to replace contaminated coolant in a Phillips set years ago.
Blue also. That was back when a local TV shop sold the coolant over the counter. They told me that the blue was the first to fail, and the theory was
that the blue CRT assembly area was closest to the cabinet assembly area.
Hence, more dust & contaminants in the air.
Freak accident years ago... A full can of beer was batted off of a counter, and landed upside-down inside of a computer, while the computer was in use.
You had to see it to believe it. What a shot! Entire mother board & every card in the expansion slots was frothing like a rabid dog. I immediately unplugged it and sprayed everything down in the kitchen sink. I blew as much water out that I could, put it on the heating register, covered it with a blanket, and let it sit for a few hours. The clock lost 15 minutes, but otherwise it worked fine.

This is not encouraging. I needed to use water because the coolant was everywhere, and probably would have been near impossible to completely remove otherwise. I'm not sure where the smoke came from, but I will take a closer look tomorrow. It seemed to emanate from the general vicinity of the audio amplifier. Hopefully, it's something simple(capacitor, resistor, etc.).

Does anyone know of a place where I might find schematics for this set? :scratch2:

P.S.--Is that a CRT from a video camcorder viewfinder in your avatar? :D

Yes - that is a 1/2 inch B&W CRT from a camcorder. I collect mini TV sets and micro CRTs and EVF units. I would love a 1/2 inch COLOR CRT, but the smallest ever made was 1.5 inches.

BTW - I was not chastising anyone for suggesting using water on circuit boards, but I have seen what damage water can do, especially to solder joints, and I would never use it - I would use isopropyl alcohol instead in an emergency situation because it evaporates very quickly.

At the very least, you will get some very good experience working on a set that you got for free - and if you do get it working properly, it will give you lots of satisfaction. Again, just be careful - regular CRT sets have lots of very high voltage in and around the CRT, but these projection sets have triple the amount.

If you're lucky, the smoke came from a wet power resister, or another component that normally operates hot. I wash stuff regular with heavily-deluted dish soap, or Windex, but it has to be bone-dry before power is applied. I had to replace contaminated coolant in a Phillips set years ago.
Blue also. That was back when a local TV shop sold the coolant over the counter. They told me that the blue was the first to fail, and the theory was
that the blue CRT assembly area was closest to the cabinet assembly area.
Hence, more dust & contaminants in the air.
Freak accident years ago... A full can of beer was batted off of a counter, and landed upside-down inside of a computer, while the computer was in use.
You had to see it to believe it. What a shot! Entire mother board & every card in the expansion slots was frothing like a rabid dog. I immediately unplugged it and sprayed everything down in the kitchen sink. I blew as much water out that I could, put it on the heating register, covered it with a blanket, and let it sit for a few hours. The clock lost 15 minutes, but otherwise it worked fine.

Now THAT is encouraging! :D I think that you might be right about the smoke, as it never really smelled. I'm letting the board dry for a few days; should I put it in the sun?

This happened to my parents set last year with a Samsung 65" RP HDTV. You might be okay still, but having smoke come up is never good... The intermittant issues you are having I hate so say will most likely be there for a long time.. Mine still glitches and the remote wont operate the set and it turns on and off on its own.. And blue convergence tweaks out and comes back.. Thats a convergence IC for sure. Mine was the blue gun too. They were heavy smokers in the house. The smoke nicotine affects the blue coolant for some reason..YOurs might have come from a smokers house as well. Good luck.. Just use windex and dry the boards for like a few days, couple hours under a heat lamp couple hours w/o the lamp, and back and fourth. Hopefully youll be ok. Good luck, that glycol is hell on circuitry and it takes a long time for the circuitry to dry out, transformers including the flyback can retain moisture especially under it where you cant access the traces.

This happened to my parents set last year with a Samsung 65" RP HDTV. You might be okay still, but having smoke come up is never good... The intermittant issues you are having I hate so say will most likely be there for a long time.. Mine still glitches and the remote wont operate the set and it turns on and off on its own.. And blue convergence tweaks out and comes back.. Thats a convergence IC for sure. Mine was the blue gun too. They were heavy smokers in the house. The smoke nicotine affects the blue coolant for some reason..YOurs might have come from a smokers house as well. Good luck.. Just use windex and dry the boards for like a few days, couple hours under a heat lamp couple hours w/o the lamp, and back and fourth. Hopefully youll be ok. Good luck, that glycol is hell on circuitry and it takes a long time for the circuitry to dry out, transformers including the flyback can retain moisture especially under it where you cant access the traces.

At this point, all I can really do is wait and hope for the best. :) I managed to procure the original remote from the folks that tossed it. BTW, I know them personally and the TV was never smoked around, so nicotine smoke isn't a problem.

Well, the book has been closed on this set, apparently the parents thought it would be a good idea to curb it while I was away from home. I was going to maybe get the speakers and some other things out of it, but of course I can't do that now. :grumpy: It's a damn good thing I hadn't put any money into it yet! :yikes: