The infamous 2 seconds to black

[shimjocky]

Re: The infamous 2 seconds to black

I can read one Q.
The top line says LT7215H.
The second says SBL1060CT.

The other one has absolutely no markings. Could they have been destroyed by heat?I will have to learn up on where to probe them for voltage.

I assume to test the transformer that all the outputs are + ? So if I probe any of the wires coming out of it and ground I should be good to go, yes?

P.S. Thanks for taking the time to explain basic things. I am sure that must get old for those who are experienced.

[EGuevarae]

Re: The infamous 2 seconds to black

I can read one Q.
The top line says LT7215H.
The second says SBL1060CT.

The other one has absolutely no markings. Could they have been destroyed by heat?I will have to learn up on where to probe them for voltage.

I assume to test the transformer that all the outputs are + ? So if I probe any of the wires coming out of it and ground I should be good to go, yes?

P.S. Thanks for taking the time to explain basic things. I am sure that must get old for those who are experienced.

Nevermind the explanation.I can explain anything you want or need, even if you think it is a 101 sort of thing. I learned that way, and I can pass that on to the newcomers. Sometimes I post comments or explanations along my posts so people that just browses around and never register to make any question directly, can benefit from the forum.
I am not that wise as PCBONEZ, Krankshaft, Wizard and many others around here (Toasty has been a great help too), but if in any form I can help, I will.

Now, back to our patient ....

The component is a Schottky Barrier (see here ).
Nevermind the T for now. Look at the picture. Do you have voltage reading in any of those two jumpers, and on the cap in the picture?

[shimjocky]

Re: The infamous 2 seconds to black

I checked both jumpers and both sides of the cap. In all cases i get a spike to less than 1 volt then it drops off to 0.

[EGuevarae]

Re: The infamous 2 seconds to black

I checked both jumpers and both sides of the cap. In all cases i get a spike to less than 1 volt then it drops off to 0.

I've run out of ideas for now. The voltage that reaches teh inverter area is 12v or more, depending on the number of lamps (I've seen 12,13 & 14 v so far). Check the voltage in the 12 V rail caps (those with 16 or 25v ratings) that you changed. You mentioned that the 12V line fluctuated before. What readings have you now on the 12v line?
Also, what V do you read on the resistor between the Schottky and a cap?
at the left):

Double check for correct orientation of caps and make sure the solder is OK (reflow if necessary). We'll be dealing only with the 12v line only, i guess.

[shimjocky]

Re: The infamous 2 seconds to black

before we go any further I have another silly question for ya. Is it ok to do all this on the bench? That is to say will the power supply work properly without being hooked up to everything?

[EGuevarae]

Re: The infamous 2 seconds to black

before we go any further I have another silly question for ya. Is it ok to do all this on the bench? That is to say will the power supply work properly without being hooked up to everything?

Not silly. That is a good question. Some PSUs work on the bench and others need load to work. If it makes you more comfortable, you can hook it up to the rest of the monitor and test. The lamps would not come on until the inverter receives the BL_ON signal, that comes from the Video board. Hook it all together, and see what happens. With the monitor in the ON state, and with signal applied (green led on the front, with VGA cable connected), redo the reads on the jumpers.
Asking is the way you'll learn, so don't be afraid. Nobody sees you, actually (except maybe the more than 10,000 members, but we don't count ...)

[shimjocky]

Re: The infamous 2 seconds to black

Thanks a bunch eguevarae.
Gonna call it quits for tonight as I have a bunch of CAD homework to do. Will get the monitor put back together on Friday and proceed with the testing.

[EGuevarae]

Re: The infamous 2 seconds to black

Thanks a bunch eguevarae.
Gonna call it quits for tonight as I have a bunch of CAD homework to do. Will get the monitor put back together on Friday and proceed with the testing.

I'll be waiting.

[PlainBill]

Re: The infamous 2 seconds to black

Transistors.
R = Resistor
F = Fuse
TH = Thermistor
D = Diode
Q = Transistor <---------------- I don't know why Q, because as you can see we had a pattern here until mr. Q arrived

Because T for transformer was already taken?

PlainBill

[EGuevarae]

Re: The infamous 2 seconds to black

Because T for transformer was already taken?

PlainBill

T in transformer, TH in Thermistor. It could have been TR.
Or, in the case of the C5707, because they fail Quite a lot and are pissing off Quite a big crowd when the Quit working on low Quality designs or implementations? ....MMMMmmmm... I wonder....

[PCBONEZ]

Re: The infamous 2 seconds to black

T was Taken.

[EGuevarae]

Re: The infamous 2 seconds to black

T was Taken.

I guess That answers my Question...

[Bobdee]

Re: The infamous 2 seconds to black

See the marked components? those are jumpers. There may be a fuse around that area, as I can't locate any on the other side of the board.

Hello Eduardo
Those 2 rectangular boxes that are in the Third picture down, by the cap you arrowed, in this link of this thread,

https://www.badcaps.net/forum/showpo...09&postcount=4

I am 99% sure they are fuses

[EGuevarae]

Re: The infamous 2 seconds to black

Hello Eduardo
Those 2 rectangular boxes that are in the Third picture down, by the cap you arrowed, in this link of this thread,

https://www.badcaps.net/forum/showpo...09&postcount=4

I am 99% sure they are fuses

Hi, Bob.
I didn't mark it, it was shimjocky. And I can put the remaining 1%, as they are fuses: 5A 250V.
They are similar to this

[sofTest]

Re: The infamous 2 seconds to black

Transistors.
R = Resistor
F = Fuse
TH = Thermistor
D = Diode
Q = Transistor <---------------- I don't know why Q, because as you can see we had a pattern here until mr. Q arrived

PF = Pico Fuse might be found in those boards.

[EGuevarae]

Re: The infamous 2 seconds to black

PF = Pico Fuse might be found in those boards.

You're right. I forgot about the picofuses.

[PCBONEZ]

Re: The infamous 2 seconds to black

HERE TOASTY
HERE TOASTY
[Self appointed resident spell checker. -> SARSC]
Pico Fuse or picofuse. ??
[I don't really care. I'm just bored.]

[EGuevarae]

Re: The infamous 2 seconds to black

HERE TOASTY
HERE TOASTY
[Self appointed resident spell checker. -> SARSC]
Pico Fuse or picofuse. ??
[I don't really care. I'm just bored.]

Can we settle for PF? less characters and no lousy spaces to mess with.
[I don't really care. It's my third night with insomnia and I'm going insane already ]

[PCBONEZ]

Re: The infamous 2 seconds to black

It's my third night with insomnia and I'm going insane already ]

Slam a stiff triple of whatever. (or fourple or fiveple if you drink often)
Before it hits take a hot hot shower.
Whack-off.
And then crash.

[sofTest]

Re: The infamous 2 seconds to black

Google seem to indicate that Pico Fuse is the most used form, and my real time dictionary in FireFox does not accept picofuse. The general rule in English is not to concatenate words, I believe. We Norwegians, using both languages, has to be on the alert on this, because the general rule in Norwegian is to concatenate such terms.