Let me take a moment to thank you all for your help on past issues.
I have no verifiable history on this TV. I'm near/in Houston so anything a few years old has seen plenty of opportunity for wet.
There are no telltale signs of any moisture at this point.
The TV has standby light and one quiet click at power on attempt and Samsung logo glows blue.
Panel stays black, w/o backlight.
____
A T-shoot as opposed to checking the record for similar faults, is newish to me but here goes:
The big caps on PSB are behaving themselves. 160 volts and change in standby, 380+ volts at power on. Takes plenty of time to drop back as the panel is switched off and main power cord disconnected.
The PSB > Main board cable is 20 pin. I can get to the odd stack simply enough and B5v and B13v are right there. A bit over on the 5V and just a bit under 13. (I know there are routinely suggestions to supply all voltages, my assumption was to disconnect at the Main and probe the female connector the for the even stack. And then I didn't.)
In any event, my search fu was suggesting this was going to be Tcon or worse, so I headed south.
I disconnected the (I assume) LVDS cable from the Tcon. In that configuration, on power up attempt I HAVE my backlights.
More reading and I locate and test F100 to see it's served it's purpose. The original 125V, 5A is blown.
Yes, testing the north/power side shows the 12.8 supply volts.
I made it to the big city in time to grab some SMD fuses for the weekend. I couldn't get the 5A in the existing form factor, but the wee cylinders fit fine. I did grab some rectangular white ones but they were 2.5A.
(Just hedging my bets. I hoped they could at least help in proof of concept, if everything continued to pear shape.)
_____
So unfortunately, the newly soldered fuse must have blown instantaneously, on it's only power up. Yes I had the ribbons exiting the Tcon connected.
Rather than try running the Tcon with another fresh fuse, but with ribbons disconnected I decided to try and see if I could find a Tcon board problem. I am delaying pulling the black tape and fussing with what is beyond the bit of ribbon I can see.
This is where my info searches diminish, and all help
would be very much appreciated.
I don't have a variable DC PS. (The stuff I have is 12v or better, and plenty of current, but...)
I don't know much of anything about circuit/board design, so I just look at all of it. (And Hope.)
I have attempted to look for Tcon SMD cap shorts to ground. I did most of the top side. Just about all acted as I hoped with ONLY the ground plane side beeping continuity at about 1 ohm.
Then I realized, I was ignoring some things that looked like tantalum caps. They are a CD prefix rather than C, and I apparently can't find that definition either.
Both CD12 and CD13, marked 33-1E20 have continuity to ground on both ends. They are about an inch and a half below the almost 13V IN fuse.
I have no idea if that is their behavior.
The Tcon board model is BN41-01790
____
Naturally any ideas on improving my next steps are welcome. ( I don't even know who the usual suspects are? )
I have no verifiable history on this TV. I'm near/in Houston so anything a few years old has seen plenty of opportunity for wet.
There are no telltale signs of any moisture at this point.
The TV has standby light and one quiet click at power on attempt and Samsung logo glows blue.
Panel stays black, w/o backlight.
____
A T-shoot as opposed to checking the record for similar faults, is newish to me but here goes:
The big caps on PSB are behaving themselves. 160 volts and change in standby, 380+ volts at power on. Takes plenty of time to drop back as the panel is switched off and main power cord disconnected.
The PSB > Main board cable is 20 pin. I can get to the odd stack simply enough and B5v and B13v are right there. A bit over on the 5V and just a bit under 13. (I know there are routinely suggestions to supply all voltages, my assumption was to disconnect at the Main and probe the female connector the for the even stack. And then I didn't.)
In any event, my search fu was suggesting this was going to be Tcon or worse, so I headed south.
I disconnected the (I assume) LVDS cable from the Tcon. In that configuration, on power up attempt I HAVE my backlights.
More reading and I locate and test F100 to see it's served it's purpose. The original 125V, 5A is blown.
Yes, testing the north/power side shows the 12.8 supply volts.
I made it to the big city in time to grab some SMD fuses for the weekend. I couldn't get the 5A in the existing form factor, but the wee cylinders fit fine. I did grab some rectangular white ones but they were 2.5A.
(Just hedging my bets. I hoped they could at least help in proof of concept, if everything continued to pear shape.)
_____
So unfortunately, the newly soldered fuse must have blown instantaneously, on it's only power up. Yes I had the ribbons exiting the Tcon connected.
Rather than try running the Tcon with another fresh fuse, but with ribbons disconnected I decided to try and see if I could find a Tcon board problem. I am delaying pulling the black tape and fussing with what is beyond the bit of ribbon I can see.
This is where my info searches diminish, and all help
would be very much appreciated.
I don't have a variable DC PS. (The stuff I have is 12v or better, and plenty of current, but...)
I don't know much of anything about circuit/board design, so I just look at all of it. (And Hope.)
I have attempted to look for Tcon SMD cap shorts to ground. I did most of the top side. Just about all acted as I hoped with ONLY the ground plane side beeping continuity at about 1 ohm.
Then I realized, I was ignoring some things that looked like tantalum caps. They are a CD prefix rather than C, and I apparently can't find that definition either.
Both CD12 and CD13, marked 33-1E20 have continuity to ground on both ends. They are about an inch and a half below the almost 13V IN fuse.
I have no idea if that is their behavior.
The Tcon board model is BN41-01790
____
Naturally any ideas on improving my next steps are welcome. ( I don't even know who the usual suspects are? )
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