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Envision EFT720 Monitor

 
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DJFreekSh0w



Joined: 26 May 2008
Posts: 8

PostPosted: Mon May 26, 2008 6:55 pm    Post subject: Envision EFT720 Monitor Reply with quote

Hello, I'm new here. I have a CRT monitor (Envision EFT720) that is broken.

This monitor belongs to a friend of mine, when he's frustrated with his PC he tends to hit the case or monitor. Confused It seems he's knocked something loose in the monitor, because it now has a rolling jumpy screen and emits a buzzing sound. However, when direct hard pressure is applied to the mid-top of the monitor top (the plastic casing) the screen becomes normal and the buzzing sound goes away. As long as the pressure is kept in place, the monitor works fine.

So, my question is, what's likely to have come a loose inside the monitor? A wire? Like at the anode cap? Or some plastic clip holding something in place? I also want to note, when you press down, you can hear and feel something sounding like it's pushing back in place.

I'm going to open it later, wanted to let it set a few days not connected to power, then discharge it using the most popular method, screwdriver, ground to metal chassis in the monitor, a few times to be sure it's properly discharged. This will be my first time doing this, so I'm a bit nerves. But I have been reading all I can on the subject, getting myself ready, etc.

I would like some input from people here, about what may be the issue. Could it be as simple as a loose wire, or something broke off holding a piece in, etc?

Thanks in advance for any helpful advice.

DJ Smile
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PostPosted: Mon May 26, 2008 7:46 pm    Post subject: Reply with quote

Look in the area where when you put pressure on it it goes normal again and solder up that area.
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DJFreekSh0w



Joined: 26 May 2008
Posts: 8

PostPosted: Thu Jun 05, 2008 8:20 am    Post subject: Reply with quote

I believe I found the problem. It's the anode cap. I was getting ready to do my discharging, but first I hooked the monitor to my PC, with the plastic housing off, turned it on, and used a piece of dry wood to press down on the top of the anode cap, and sure enough the monitor cleared of it's problems. So it must have been a loose anode cap, so I thought.. I turned it of, unplugged all, and was slightly pulling back the rubber cap to get the discharge tool's tip under the edge of the cap, and the cap popped off! I was scared at first, with visions of nasty shocks coming my way.. But I cooled down, and took a careful closer look, and saw this..
.. it seems the prongs inside have broken/worn into, or something. I guess that's what the problem was. Now, how to fix it? I stopped with my discharging plans, not sure which end, or both, or even if I have to now. I just put the plastic housing back on, and will do some more research. Man, I sure wish my local library had some monitor repair books! Confused I have a few old monitors, I wonder if I could use the anode cap and wire from one of them? Or is it a model fit type thing only?
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DJFreekSh0w



Joined: 26 May 2008
Posts: 8

PostPosted: Thu Jun 05, 2008 11:00 pm    Post subject: Reply with quote

Well, today I took a closer look at the anode cap and wire, it's a mess! The wire is not removable, it's built into a plastic piece, that is surrounded by a metal brace, all appear to be soldered to the circuit board. How do you get to that safely? Shocked I don't know enough about it to feel I should try to disassemble all of the stuff to get to it. So, maybe somehow get the left over prong bits out of the suction cup anode cap, and replace it with one from one of my old junk monitors. I pulled the suction cup back to look, and I see the prongs were soldered onto the wire. So, I'll have to do some solder removing and re-soldering. Confused Or, cut the wire into, and just redneck it and cut the wire off the old monitor and splice it together. Razz
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DJFreekSh0w



Joined: 26 May 2008
Posts: 8

PostPosted: Mon Jun 09, 2008 4:54 am    Post subject: Reply with quote

I did it! I fixed the monitor. Very Happy

I pulled the old broken clip through the suction cup, removed it, and replaced the clip with one from a much older monitor (1992). It looked a bit different, but it worked great! The monitor works like new.


the old broken clip on the wire


the pieces of the broken anode clip


the wire with the anode clip from the older monitor, a bit different, but it worked
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vtech



Joined: 08 May 2006
Posts: 1264
Location: USA

PostPosted: Mon Jun 09, 2008 6:36 am    Post subject: Reply with quote

As the saying goes, if there is a will, there is a way... Good job

---have to always be cautious around HV though Cool
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DJFreekSh0w



Joined: 26 May 2008
Posts: 8

PostPosted: Mon Jun 09, 2008 5:17 pm    Post subject: Reply with quote

Thanks. I was nerves, this was the first time I have ever opened a monitor up and messed around inside. I was always afraid after I learned they can carry such a strong charge, even when off. And I have no official training in the area. So, it was a matter of mind over fear here. Wink
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