Author Topic: Water damaged CRT TV  (Read 11034 times)

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Offline stj

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Re: Water damaged CRT TV
« Reply #50 on: August 07, 2016, 03:52:45 pm »
a trick i used to use is swapping 2 colours over at the point of origin - in this case the rgb matrix decoder - to see if the colour on the screen changes.
 

Offline Srbel

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Re: Water damaged CRT TV
« Reply #51 on: August 07, 2016, 04:04:12 pm »
Ah, the connector is asymmetrical, so it only fits in one orientation.

The problem is that I only get something on the screen if those colour signals are disconnected. When I plug them back in, I get nothing on the screen. :/
 

Offline stj

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Re: Water damaged CRT TV
« Reply #52 on: August 07, 2016, 06:00:49 pm »
check any white or gray resistors on the rgb pcb, philips used resistors as fuses.
 

Offline Srbel

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Re: Water damaged CRT TV
« Reply #53 on: August 07, 2016, 06:07:20 pm »
There is one, and it is fine. Measures 15 ohms.
 

Offline Srbel

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Re: Water damaged CRT TV
« Reply #54 on: August 09, 2016, 10:42:55 am »
Any more ideas?
 

Offline Srbel

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Re: Water damaged CRT TV
« Reply #55 on: August 11, 2016, 07:10:58 am »
I am stuck. I don't know what board is at fault. I don't know how CRT should behave, what signals it should get and so on. And this is the last day I can use for repair. After this, I have no more time for it. :(
 

Offline stj

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Re: Water damaged CRT TV
« Reply #56 on: August 11, 2016, 02:02:51 pm »
check all the psu voltages against the schematic.
if you have HT then the problem is in the decoding or gun-drive area.
 

Offline Srbel

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Re: Water damaged CRT TV
« Reply #57 on: August 11, 2016, 02:43:01 pm »
There are hundreds of voltages in schematics. They are not accessible (no test points). I would need to hunt down a certain capacitors on the PCB and then solder a wire on the bottom side, then get everything back in place in order to measure it. I dont want to poke around with a few 10s of KV present.

I don't know what HT stands for.

Thanks for help, but time is up. So, I have to give up. :(
 

Offline MosherIV

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Re: Water damaged CRT TV
« Reply #58 on: August 11, 2016, 03:08:50 pm »
Quote
I don't know what HT stands for.
High Tension.

Tension is another term used for very high voltages.
 


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