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Discussion Starter #1
My hitachi rear projection tv will turn on and work fine for about ten seconds the it looks and sounds like the tv shuts off I have no picture or sound but the red indicator light on the front of the tv is still on like the tv is still on. This is the only tv I have. I would greatly appreciate it if someone could help me try to figure out what's going on with so I can have tv for me and my kids again.

Thank you Brad
 

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Check the state of the LEDs on the power supply.
 

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Discussion Starter #4
What do the LEDs on the power supply mean. All of them are on when I turn the tv on and they all stay on even when the picture goes away
 

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The LEDs tell you that each supply is up. If they all stay lit the set is powered and you likely have a signal routing or processing related problem.
 

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Discussion Starter #7
lcaillo said:
The LEDs tell you that each supply is up. If they all stay lit the set is powered and you likely have a signal routing or processing related problem.
Ok what should I be looking for to try to fix it I know a little bit about soldering and repair but not so much about disguising what's wrong that's what I would like the help with

Thanks brad
 

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What should I be looking at or testing to try to figure out what I might need to replace and does anyone have schematics for this model tv or where I can look at a free one online
 

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We have links to sites with manuals in the stickies in the service and support forums and we have sources for manuals in the vendor listings.

Do you get menus? PIP? Same on all signal types.
 

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Discussion Starter #10
lcaillo said:
We have links to sites with manuals in the stickies in the service and support forums and we have sources for manuals in the vendor listings.

Do you get menus? PIP? Same on all signal types.
No once the picture goes out I don't have anything it's just a black screen. It's like the tv shut off but the power light remains on. I lose sound when the picture goes too
 

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Do you have a raster at all? Is the high voltage present and H&V scanning? Are filaments lit?
 

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Discussion Starter #12
lcaillo said:
Do you have a raster at all? Is the high voltage present and H&V scanning? Are filaments lit?
I'm not sure what a raster is and how do I tell if the high voltage present and H&V are scanning and yes the filaments are lit all three stay on just no picture

Thanks for the help so far
 

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A raster is the background scanning of the phoshphor. If you turn up one of the screen controls and see a full field of light, you have a raster, which means that HV, scanning and filaments are present. HV can be tested in several ways, but the most obvious is the static charge that you hear as the HV comes up or goes down. Scanning can be checked with a scope or with a multimeter, but you have to be careful with horizontal measurements as they are often out of the range of most meters and scopes for direct measurement. Filaments are easy to see as the glowing element at the base of the CRTs.

If you are not familiar with these aspects of TV repair, troubleshooting these areas is not recommended. It can be dangerous and critical work if it goes beyond a simple repair. If you have a raster and no video nor OSD or menus, and you know your sources are not the problem, you will have to troubleshoot the signal path. Some of that can be done with a good meter, but a scope is best (and necessary for some checks). Having a service manual and knowing how to read a schematic may be essential.
 

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Discussion Starter #14
Is it possible that there could be a bad connection on one of the boards because i tapped on the board on accident and it made the tv work for about 3 weeks then it started acting up again and I would tap on the board again and it would work again but now it won't work. Turns on with no sound or picture. Or could this be a bad part on the board that when I tapped on the board it caused it to work temporarily?
 

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Is it possible that there could be a bad connection on one of the boards because i tapped on the board on accident and it made the tv work for about 3 weeks then it started acting up again and I would tap on the board again and it would work again but now it won't work. Turns on with no sound or picture. Or could this be a bad part on the board that when I tapped on the board it caused it to work temporarily?
I know nothing about CRTs or your particular model but perhaps you have a loose ribbon or wire. When you "tapped" it (are you sure you didnt do more than that? :whistling:) maybe the wire or ribbon made contact again. I would open her back up and (with the TV unplugged) go through and jiggle/reseat as many components as you can put your hands on. If anything is unseated this could help. If nothing else you would have gotten to see and touch each component so when you are going through the service manual it will be easier for you to understand the repair. Leonard maybe right about needing about specialized equipment to troublshoot this one if the problem isnt as simple as a loose wire or doo-dad.

Good luck
 

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Discussion Starter #16
What would make the set shut down right after i tern it on. I just tried to turn it on again just to see if it would decide to work and now once it come on it's on for about 2 seconds and then it completely shuts down and the only way to get it to try to turn back on is to unplug it and plug it back in.
 

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What would make the set shut down right after i tern it on. I just tried to turn it on again just to see if it would decide to work and now once it come on it's on for about 2 seconds and then it completely shuts down and the only way to get it to try to turn back on is to unplug it and plug it back in.
It could be a fail safe to prevent the tv from short circuiting or burning itself out. I would scour the net and try to find a service manual with troubleshoot from there. Without a service manual you are really shooting in the dark.
 

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These sets have been known to have leaky caps sometimes. Look for wet spots on the boards and dark legs and circuit traces.
 
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