Ok as the titles says, I'm working on a Insignia NS-LTDVD26. Everything seems to work fine (DVD player, antenna, rca, vga, blah blah) for about 3-6 minutes and it turns off, sorta.
So let's start: standby LED comes on "red" voltage checks good.
Turn on the set, LED turns blue, good to go.
When the set "turns off" audio and video turn off, but blue LED stays lit. Doesn't go back to standby red, doesn't turn off, stays blue.
The unit won't turn off when I hit the power button, I have to literally unplug it (or turn off the power strip it's plugged into)
Now I say to myself, "this seems like a classic cap issue", especially after seeing a power board full of Capxon caps. eekk! So... I order my caps get them in and change out all but the main. (actually I ordered the wrong size diameter cap for C113. Left the original cap [samxo 220uF 16v] in the board. I could get the one I ordered to fit if I need to but there is going to be some rigging. If not, i'll order another. But at this time I'm not sure it's really the problem.)
Ok so I power up the unit knowing I just brought the nearly dead back to life. Wrong! It does the same thing by shutting off after 5 mins. So I crack open the back, plug the unit back in, turn it on and observe, listen and smell. Well after 5 mins. it shuts off again, but that's when I saw something really cool. A green LED on the power board "DB9A" is blinking in reps of 8, then pausing a second, then repeats as long as I keep the power on. I haven't found anything online about what that green LED is trying to tell me, but besides the blue power LED, this green LED is letting me know there is still power working.
In the mean time I find a schematic for this power board at:
http://monitor.net.ru/forum/files/mi..._______205.pdf
For me it's like reading another language that you only know how to read "hello", "goodbye", "what time is it" and all of the main curse words (hey those are important to know).
OK now it's time to test transistors. I haven't messed with them before. I test everything that looks like a transistor only to realize they're not all transistors....I think. I'm testing in board with my multimeter set to diode. OK I test:
Q102(transistor)
1-3=109
1-2=530
2-3=OL
3-1=109 (UH OH!)
3-2=410
2-1=OL
Q103(transistor same type as Q102
1-3=109
1-2=527
2-3=409
3-1=108 (HMMM!)
3-2=409
2-1=OL
Q104 (transistor)
1-3=OL
1-2=OL
2-3=559
3-1=719 (LOOKS GOOD)
3-2=559
2-1=OL
BD1 (Bridge rectifier)
1-2=550
1-3=550
1-4=520
2-3=530
3-4=550
4-3, 4-2, 4-1, 3-2, 3-1, 2-1 = OL
Seems good
Q101 (transistor)
1-3=694
1-2=519
2-3=OL
3-1=1013 (OH CRAP!!)
3-2=1979
2-1=OL
D101 (I think it's a diode rectifier)
1-2=416
2-1=OL
Seems good
D103 (I think it's a diode rectifier and a zener *what ever that is*)
1-3=001
1-2=173
2-3=(number climbs up past 2000 then OL)
3-1=001
3-2=170
2-1=OL
Not sure if this is testing good, rather what to be looking for to know that it's testing good.
Q8 (transistor) *backside of the board*
1-3=OL
1-2=OL
2-3=OL
3-1=OL
3-2=556
2-1=OL
Is that testing good?
Q101, Q102 and Q103 seem bad to me. I haven't pulled them out of the board to test yet. As you can see they are attached to heatsinks. I don't have any thermal paste except the arctic silver I bought long ago for my PC CPU/Heatsink. Not sure if I want to really use the good stuff on this project or if that is even stuff that should be used on this.
So.. beyond the first question of whats the conclusion of my tests, the 2nd question would be what paste do I use when I replace the transistors?
3rd question would be; how do you order the resistors? I guess better, what type are they? When I go to DigiKey and type in K3316 it comes back with the message "your a moron, try again", when I do a search of transistors, there are a bunch of different types. I could go through looking at the pictures to determine which types I'm looking for, but could still be wrong.
Q102 & Q103 clearly say on them:
K3316
8C
As for Q101, I think it says:
FB G53
FOFF
13N5CC
I'm sure I will be able to see that one better when I pull it out. Well, that's where I'm at. I'd rather not go any further without advice.
Hope the pics are good enough. Tried to help a little and explain better with the last 4 pics
So let's start: standby LED comes on "red" voltage checks good.
Turn on the set, LED turns blue, good to go.
When the set "turns off" audio and video turn off, but blue LED stays lit. Doesn't go back to standby red, doesn't turn off, stays blue.
The unit won't turn off when I hit the power button, I have to literally unplug it (or turn off the power strip it's plugged into)
Now I say to myself, "this seems like a classic cap issue", especially after seeing a power board full of Capxon caps. eekk! So... I order my caps get them in and change out all but the main. (actually I ordered the wrong size diameter cap for C113. Left the original cap [samxo 220uF 16v] in the board. I could get the one I ordered to fit if I need to but there is going to be some rigging. If not, i'll order another. But at this time I'm not sure it's really the problem.)
Ok so I power up the unit knowing I just brought the nearly dead back to life. Wrong! It does the same thing by shutting off after 5 mins. So I crack open the back, plug the unit back in, turn it on and observe, listen and smell. Well after 5 mins. it shuts off again, but that's when I saw something really cool. A green LED on the power board "DB9A" is blinking in reps of 8, then pausing a second, then repeats as long as I keep the power on. I haven't found anything online about what that green LED is trying to tell me, but besides the blue power LED, this green LED is letting me know there is still power working.
In the mean time I find a schematic for this power board at:
http://monitor.net.ru/forum/files/mi..._______205.pdf
For me it's like reading another language that you only know how to read "hello", "goodbye", "what time is it" and all of the main curse words (hey those are important to know).
OK now it's time to test transistors. I haven't messed with them before. I test everything that looks like a transistor only to realize they're not all transistors....I think. I'm testing in board with my multimeter set to diode. OK I test:
Q102(transistor)
1-3=109
1-2=530
2-3=OL
3-1=109 (UH OH!)
3-2=410
2-1=OL
Q103(transistor same type as Q102
1-3=109
1-2=527
2-3=409
3-1=108 (HMMM!)
3-2=409
2-1=OL
Q104 (transistor)
1-3=OL
1-2=OL
2-3=559
3-1=719 (LOOKS GOOD)
3-2=559
2-1=OL
BD1 (Bridge rectifier)
1-2=550
1-3=550
1-4=520
2-3=530
3-4=550
4-3, 4-2, 4-1, 3-2, 3-1, 2-1 = OL
Seems good
Q101 (transistor)
1-3=694
1-2=519
2-3=OL
3-1=1013 (OH CRAP!!)
3-2=1979
2-1=OL
D101 (I think it's a diode rectifier)
1-2=416
2-1=OL
Seems good
D103 (I think it's a diode rectifier and a zener *what ever that is*)
1-3=001
1-2=173
2-3=(number climbs up past 2000 then OL)
3-1=001
3-2=170
2-1=OL
Not sure if this is testing good, rather what to be looking for to know that it's testing good.
Q8 (transistor) *backside of the board*
1-3=OL
1-2=OL
2-3=OL
3-1=OL
3-2=556
2-1=OL
Is that testing good?
Q101, Q102 and Q103 seem bad to me. I haven't pulled them out of the board to test yet. As you can see they are attached to heatsinks. I don't have any thermal paste except the arctic silver I bought long ago for my PC CPU/Heatsink. Not sure if I want to really use the good stuff on this project or if that is even stuff that should be used on this.
So.. beyond the first question of whats the conclusion of my tests, the 2nd question would be what paste do I use when I replace the transistors?
3rd question would be; how do you order the resistors? I guess better, what type are they? When I go to DigiKey and type in K3316 it comes back with the message "your a moron, try again", when I do a search of transistors, there are a bunch of different types. I could go through looking at the pictures to determine which types I'm looking for, but could still be wrong.
Q102 & Q103 clearly say on them:
K3316
8C
As for Q101, I think it says:
FB G53
FOFF
13N5CC
I'm sure I will be able to see that one better when I pull it out. Well, that's where I'm at. I'd rather not go any further without advice.
Hope the pics are good enough. Tried to help a little and explain better with the last 4 pics
Attached Files
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