Hey everyone, I stumbled upon this great resource and am looking for some help. I have worked on all different kinds of electronics, but never a TV, so I am having fun learning all new things.
I was given a samsung plasma because it wasn't turning on. When I first plugged it in, the Samsung start up chime would happen, but no image. The red LED on the front would blink 6 times and stop. My first thought was bad caps or blown fuse, being inexperienced with this kind of stuff. So, I pulled off the back, inspected all the caps and checked the fuse, all seemed to check out. THe logic board LED stayed on for 5 secs, turned off for a second or two, then back on for 5. I began doing research, and first tested the Vs and Va voltages. After checking it a few times, I realized that the power supply was shutting down very soon after the chime, so I only had a few seconds each time to check the voltages. The Vs hit 209v and the Va was 59v, per spec. So that was good. Next, I tried checking the Vscan and Ve, I found the Vscan, but really didn't seem to get the -187v. I didn't get a negative at all actually, it was something like 5v. I couldn't find the Ve (yet).
So, not knowing where to go next and watching tons of videos/reading tons of forums, I started pulling apart the y buffer to test the chips. They seemed ok, but my multimeter isn't very fancy.
Next, I decided to pull the X-buffer off and inspect it all thoroughly, nothing obvious.
So, now I'm here today. I put everything back together, but some new behavior is happening. Once everything is connected, the TV will not chime at all, and the logic board just flashes occasionally. If I disconnect the X-buffer from the power supply, the TV will then chime when plugged in, and then chimes a few more times. Another thing is the Vs and Va voltages are gone. I noticed one thing. With the X buffer, there is continuity between Vs and ground. The moment I plug in the power supply to the buffer, the Vs grounds. There is nothing visibly wrong with the buffer, and I am not sure why it would have changed after disconnecting it.
I would love to solve this. It's an interesting and new challenge. Please, if anyone could help me, I would be greatly appreciative.
I was given a samsung plasma because it wasn't turning on. When I first plugged it in, the Samsung start up chime would happen, but no image. The red LED on the front would blink 6 times and stop. My first thought was bad caps or blown fuse, being inexperienced with this kind of stuff. So, I pulled off the back, inspected all the caps and checked the fuse, all seemed to check out. THe logic board LED stayed on for 5 secs, turned off for a second or two, then back on for 5. I began doing research, and first tested the Vs and Va voltages. After checking it a few times, I realized that the power supply was shutting down very soon after the chime, so I only had a few seconds each time to check the voltages. The Vs hit 209v and the Va was 59v, per spec. So that was good. Next, I tried checking the Vscan and Ve, I found the Vscan, but really didn't seem to get the -187v. I didn't get a negative at all actually, it was something like 5v. I couldn't find the Ve (yet).
So, not knowing where to go next and watching tons of videos/reading tons of forums, I started pulling apart the y buffer to test the chips. They seemed ok, but my multimeter isn't very fancy.
Next, I decided to pull the X-buffer off and inspect it all thoroughly, nothing obvious.
So, now I'm here today. I put everything back together, but some new behavior is happening. Once everything is connected, the TV will not chime at all, and the logic board just flashes occasionally. If I disconnect the X-buffer from the power supply, the TV will then chime when plugged in, and then chimes a few more times. Another thing is the Vs and Va voltages are gone. I noticed one thing. With the X buffer, there is continuity between Vs and ground. The moment I plug in the power supply to the buffer, the Vs grounds. There is nothing visibly wrong with the buffer, and I am not sure why it would have changed after disconnecting it.
I would love to solve this. It's an interesting and new challenge. Please, if anyone could help me, I would be greatly appreciative.
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