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Discussion Starter #1
Can anyone please advise me on a problem I have had for a while on my ecp4000. basically the picture is way to bright as if the contrast is turned way up, on images with sky in them, it is un-watchable, using the contrast control does not help, with it turned down the picture just blacks out, its as if the contrast control only adjusts the brightness? This fault seems to appeared after the resistor on the focus board was replaced. I`ve tried to follow the service manual to re-set the unit, ie 140v at K etc. etc.The picture was still the same after a evenings work. :(

Any advise gratefully received.

Gary.
 

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I'd say that your G2 is cranked too high (pots on the focus board that aren't the focus pots) but you say that it goes dark when the contrast is down. What about the brightness control on the remote? Does it do anything? You've got the cathode set to 140V brightness probably isn't it. What about the source? Has anything changed there? Cable termination?


Cary
 

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Did it happen all of the sudden or has it been this way for awhile? An interesting thing just happend with Jeep Lover and I...I bought an extra input board from him, and it turns out that the 75 ohm terminating resistors on the one I got, as well as the other ones he had, had all been lifted on one side. These boards (according to Sean's source) had been in a switcher. Sean is now having problems with one he is modding because the pix is so bright that it is blooming and crushing with C/B at less than 3. You didn't happen to put in a new board or anything lately did you?
 

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Jay is right,

I got the boards out of a switcher. Interestingly enough, though, the board that came with my 3000 had the resistors this way. That is why I thought it was normal. Look for the resistors to still be in place with one end sticking straight up.


Sean


I just reconnected the resistors and will do some re-calibrating tonight...
 

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Discussion Starter #5
The unit was working OK when I got it several years ago, I always use composite input that hasn't changed, the fault happened after the unit was taken down and the resistor on the focus board was changed as the focus was out on all three tubes. The unit has been rarely used since then as the picture was only good for a play-station.

As far as the controls, brightness and contrast seemed to do the same job picture goes light and dark at about the same rate. I`ve tried what seems like all the combinations with the on screen controls. But since going through the set up manual the brightness control seems to make no difference where its set.

But as I said the picture is still the same as when I started.

Thanks for help.

Gary
 

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if you are using a composite/S-video input board, make sure that you terminate the unused input. It's been a long time since I had one of those, but my memory is that there was an actial terminator for composite and a switch for S-video. Maybe they were used in conjunction...I can't remember...but that definately sounds like an unterminated input. Who took the pj down as if it was a switch on the board it could have easily been hit. My memory is that the switch is exposed on the rear of the unit.

Check it out and let us know!
 

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I believe you need the terminator on and the switch set to 75 ohms.


Chip S.
 

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Discussion Starter #8
The unit only has composite input or RGBHV there is no svideo input and I cant find any switches on the rear.

I will re-do the G2 pots and try again.

thanks

Gary.
 

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The S-video is a dual BNC connection, NOT a typical 4 pin connection that you're used to. You need a terminator on the "loop out" side of that video connector. You can use an antenna type, "F' connector terminator with a "F" to BNC adaptor, available at radio shack.
 

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Hell,

I have a real S-video card with the standard connector if you want it. I'd like to get 50 dollars for it. Let me know. I'm starting to feel like a used car salesman...


I guess that's what you get when you buy 2 back up machines due to obsesion!


Sean
 

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Discussion Starter #11
Well further to my last post last night I adjusted the G2 pot as per the service manual, still the same :( When operating the controls the brightness has NO effect on the display min or max it stays the same. Only contrast seems to work BUT that looks like its adjusting the brightness ? maybe just me, anyway, I thought nothing to loose, wound up the G2 pot to almost max and the picture is the best so far looking almost normal.

Now have I caused the fault in messing with the service settings OR has something failed on it ????

Help !!

Thanks

Gary.
 

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Gary,

When you say you adjusted the pot...and that you have it up to max...you are adjusting all 3 correct? My pots are nowhere near max. Did you terminate the other BNC connector on the input board? And I know you said you tried to adjust 140v at k...what did you end up with? See, the the picture is best when the voltage at k is lowest. Kind of backwards to what you would think. If you kept turning and turning and never could get to 140v, that could be the probelm. I remember a post that with this voltage incorrect, the brightness controls would not work. Just a thought you might want to double check.
 

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Not only that, those pots aren't the greatest (the ones that adjust the K cathode bias) so you coul end up with it being something lower than 140V (bright screen) when you thought you had it. Check it again. Those pots have flaky spots in them at some points in their rotation (mine do). You have to crank them left/right a few times to clean the spot for the wiper in the pot.


Cary
 
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