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Discussion Starter · #1 ·
So my ECP 4000 has been down for a while. At first I thought it was my neck board - but I have changed them and decided that is not the problem. I finally got a video camera so here is a video of the problem. Any help is appreciated.

projector.asf


Thanks in advance.

-Brian
 

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Well that was cute! My Windows player showed that on about a 1" X 1" screen!


It sounds like your one CRT is arcing. If so, you have to change it.


Disconnect the red HV lead to each tube one at a time to see which tube is causing it. (You might already know, the resolution and the pix on my screen was too small to see)


The noise gives it away; find the source of the noise and you have found your problem.


Curt
 

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Curt- That's odd, the video took up half my screen. Im using MP7. :-?


Brian-


In one of the scenes, the arcing is occurring in the spark gap of the CRT connector, not in the CRT. Arcing in the spark gap is generally caused by excessive dust buildup or excessive voltage. Since it is happening on more than one CRT you can basically rule out the dust issue.


In another scene you can see arcing on the circuit board- but I cant see what exactly it is because the video is not zoomed in enough. This arcing could be from a cracked/broken component, excessive voltage, etc. Most likely the arcing at the CRT and one this board are being caused by the same failed component/module.


Ive seen similar arcing in several RPTV over the years which was caused by a bad focus module. I'm not familiar with ECP, but based on what I saw I would be suspicious of any focus/voltage divider components.


Hope this helps- let us know what you find.

--Kieth
 

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Discussion Starter · #4 ·
Kieth - yes thank you.


The arcing does occur at both the blue and red tube connectors.


I do believe it is a problem w/ bias module because shortly after I did the focus mod and messed around w/ bias board the arcing occurred.


The sparking you see on the "unknown" board is actually the neon lights on the bias board flashing - there really is no arcing going on there.


So now - what could be wrong with the bias board?


-Brian


Oh and Curt - maybe if you save the file to the hard disk and open in media player from there - it should take up most of your screen.


Thanks for watching my video.
 

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Neon bulbs are sometimes used as a type of voltage regulator/surge supressor. If they are arcing it just helps to confirm that something has failed and is allowing voltages to reach levels one would not normally see. I still have that feeling of a bad focus/divider based on my previous encounters...


Did you remove any boards? If you removed any boards you might take the board back out and look for physically shorted components. Sometimes component legs or the components themselves can be bent - shorting against something they shouldn't...


Perhaps someone with some ECP experience has some more ideas?


--Kieth
 

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Discussion Starter · #6 ·
Thanks Kieth -

I am gonna check out your suggestions.

If I can't figure it out - I am gonna scrap it and sell off the parts - it is too frustrating.


-Brian
 

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This is pretty simple Brian, If your PJ wasn't arcing before you did your "mods" to the bias module, and started arcing afterwards, then all fingers point to your "mods" and any other re-installation error that may have happened. The CRT's are arcing in the sockets because they are now seeing too much voltage, indicating that the mod you probably performed was the 44meg resistor, and you got the values wrong, thereby sending too much focus voltage to the CRT's. This is just a hypothesis - it could be something totally different, but it IS stemming from the bias module. I'd suggest obtaining a known good used one from someone who maintains a parts PJ and just throw this one away at this point.
 
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