Spectroniq PLTV-3250 wont start

[zape]

Re: Spectroniq PLTV-3250 wont start

replaced Q7 and ZD4 (and capacitors of course) and it TV from 2006 works now.
digi-key parts used:
MMBT2222ALT1GOSCT-ND
BZX384C15-E3-08GICT-ND

[zape]

Re: Spectroniq PLTV-3250 wont start

Hi
I'm trying to fix the Protron TV with exactly the same PSU model.
I do get +5v sb but when I load it it goes down to ~3v and fluctuates.
The symptoms on the TV: blue led blinks when pressing power button, does not power on.

I read all the thread and I see that I must replace all Capxcon caps (I only replaced bulged ones and it did not help)

So I'm going to order all caps from digikey to replace, any other things I should order just in case?
I tested Q7 and ZD4 and they seem to be good (I tested them in circuit though) My thinking is that since I get somewhat +5vsb then there is no need to replace Q7 and ZD4...

Thanks

[ndawgtkd]

Re: Spectroniq PLTV-3250 wont start

Has anyone came up with a parts list to shotgun this board to cover most everything that seems to be commonly found wrong on this board? I am going on a small vacation in a few weeks to visit family and they have this same tv with the same problem.. Seems to be totally dead.. I was hoping to just order a bunch of parts and take them with me.. And that way I should be armed with everything that I MIGHT need. Thats if its not some off the wall problem, which seems to happening to me a lot as of late

See page 5.

[lilmonk3]

Re: Spectroniq PLTV-3250 wont start

Has anyone came up with a parts list to shotgun this board to cover most everything that seems to be commonly found wrong on this board? I am going on a small vacation in a few weeks to visit family and they have this same tv with the same problem.. Seems to be totally dead.. I was hoping to just order a bunch of parts and take them with me.. And that way I should be armed with everything that I MIGHT need. Thats if its not some off the wall problem, which seems to happening to me a lot as of late

[ndawgtkd]

Re: Spectroniq PLTV-3250 wont start

So if ZD3 is in fact a 15V Zdiode would http://www.digikey.com/product-detai...2-1-ND/1163093 be an acceptable replacement? I am very uncertain as to which parts can be replaced with what so I have been trying to replace everything exactly. This is the only part that it doesn't seem I will have the chance too.

[Jochem]

Re: Spectroniq PLTV-3250 wont start

Also, IC1 (L6598D) was blown as well as the 10 ohm resistor in the high fet gate drive.

Mind that Q11 is a general purpose PNP (not NPN like Q7, as someone suggested somewhere). Mine turned out to be okay.

All working fine now.

[Jochem]

Re: Spectroniq PLTV-3250 wont start

Mine had Q1 and Q2 shorted (and the fuse out), and it also looked like ZD3 was shorted. When I took ZD3 out I still measured low resistance, but not entirely 0 ohm (and more than my meter's leads). Apparently this is how the circuit should be.

I also took the time to verify if ZD3 was still allright after I baked it off the PCB (it was glued as well, so it got a bit hotter than I wanted). ZD3 was still okay, but it turns out to be a 15V zener, not 16V as someone suggested (I guess people keep copying what they find on the internet). It has marking code '15B' on it, which could very well be Vishay's TLZ15B. Page 3 of the datasheet shows this marking code:

On my PCB, Q1 and Q2 were 2SK3667 FETs, but this can vary by revision I suppose. I guess I'll replace them with an STP11NK50ZFP from ST. Only Pd is somewhat inferior, but I think the insulated TO-220FP will be the bottleneck in terms of dissipation anyways.

[budm]

Re: Spectroniq PLTV-3250 wont start

This how I fixed them: http://s807.photobucket.com/albums/y...20PLTV%203250/

[Dalieus]

Re: Spectroniq PLTV-3250 wont start

Hi,

Here is breakdown of the PSU repair for component failure, not power surge related failures.

Model: PLTV-3250

1. Replace all the caps (usually the single large cap stays good) and check cables.
2. If your missing 5v SB check/replace Q7 and ZD4. Check 5v SB.
3. If no 5v SB, replace IC2.
4. If no power on, replace Q4 and ZD3.
5. Check Q1 and Q2.

Move on to Main Board

Parts:
ZD4 - 15V Zener Diodes BZX384-C15,115
ZD3 - 16V Zener Diodes PDZ16B,115
Q7 - Transistor MMBT3904
IC2 - IC PFC TEA1532A
Q4 - Mosfet STP4NK60ZFP or 2SK3568
Q2 - Mosfet 2SK3568

Good Luck,
Dal

[Dalieus]

Re: Spectroniq PLTV-3250 wont start

Hi,

I'm working on this same model PSU and I get voltage on the Primary side, but stops at the secondary and no 5V standby.

I wanted to know the specs for the Q7 15v Zener Diode so I can order the right one (voltage breakdown, polarization, etc.)

My board also had a half melted 497-5980-5-ND Mosfet. I ordered two of the MPS2222A since they seem to be failure prone.

Does anyone know where a 10V 1000uF Cap goes on the board, I got one sent in a kit but I dont see it on the board. Maybe the kit is wrong.

Thanks,
Dal

[alfa88]

Re: Spectroniq PLTV-3250 wont start

I did something stupid. My spare FSP1953-F01 went bad and I pulled out bulged caps, CS20,CS21. CS25, CS27, and CS29 . I then got distracted and misplaced the bad caps. I've figured out all but CS29. Can someone do me a big favor and enlighten me as to the value?

[PlainBill]

Re: Spectroniq PLTV-3250 wont start

Could the no-name (Newark or digikey I'm sure) caps I used cause this sort of problem? What else should I really look for?...

Thought I would ask.

Thanks guys!

All capacitors are not created equal. A capacitor that is suitable for use in a radio is probably unsuitable for a monitor. The caps in the power supply are under unusual stress, they require low ESR caps. I personally prefer Panasonic FM, FR, and FC, series but will cheerfully use Nichicon, United Chemicon, or Rubycon if they provide the performance required.

I would say yes, using general purpose caps might cause this problem, but there are also other causes. One I would suspect is the largest (typically 450 volt, 100uF). There is a small cap (typically under 100uF, 50 V) near the SMPS controller that can cause all sort of weird problems as it fails.

PlainBill

[pacmanretro]

Re: Spectroniq PLTV-3250 wont start

Could the no-name (Newark or digikey I'm sure) caps I used cause this sort of problem? What else should I really look for?...

Thought I would ask.

Thanks guys!

[pacmanretro]

Re: Spectroniq PLTV-3250 wont start

the 3 on the top left of the first pic that have the black dot on them are the only ones I replaced. They were physically broken open at the top. I used a Tenma cap meter on the rest and they seemed ok, so hadn't messed with them.

IDK the brands - top left little blue guy says 28IVGN (brand - product? IDK).
Other two say KME.

These were some caps I just happen to have with my monitor parts. I honestly don't know their ESR...

[PlainBill]

Re: Spectroniq PLTV-3250 wont start

Very good pictures. The erratic output from the Standby supply while the main board is hooked up indicates either a problem with the main board, or a problem with that portion of the power supply. Please indicate which caps you replaced on the power supply (loading the picture into Paint and placing a dot on each new cap is sufficient), and also what brand and series of caps you used.

PlainBill

[pacmanretro]

Re: Spectroniq PLTV-3250 wont start

Ok, I tried to take a few pics. Top and bottom side of P.S. board (2 of bottom), one of the three other boards. and one each of the three up close.

Hope these help a little...please lmk if I need to take pics of other items.

Thank you very much!

[retiredcaps]

Re: Spectroniq PLTV-3250 wont start

Any help???? Ideas???

Post clear focused top down view pictures of all your boards (both sides) following the instructions below exactly.

[pacmanretro]

Re: Spectroniq PLTV-3250 wont start

Ok, so while I did measure that the 5VDC standby is there, I did so before reconnecting everything.

With all connections reattached, the 5VDC is NOT a constant 5V but rather is constantly fluctuating (on my DMM)! Best as my digital meter is telling me, it is going up to nearly 5 then down to about 1.4 or so...

I cannot get any 3.3v reading. I do not see a standby led or anything so really don't think the controls are even working.

Any help???? Ideas???

Thank you!!!!!!

[PlainBill]

Re: Spectroniq PLTV-3250 wont start

So got some parts in and replaced caps and Q7. I now have my 5V standby, but unit is still dead...

My understanding is that the 3.3VDC signal voltage is a brief voltage sent back to the power supply when the power button is pressed enabling the turn on of the 16 snd 24vdc section; correct?

So whether using the power button or remote, I should be able to meter the signal voltage. If it does appear, I need to check things like Q11.

Anyone have any idea what to look for if I have the 5VDC standby, but can't get it to send back the 3.3VDC for turn on?

Thanks!!

There is a small error in your description. When you press the power button an input to the controller on the signal board changes level as long as the button is pressed. The controller reacts by 'flipping' the state of the PS_ON (or some equivalent name) signal to the power supply. That line stays in it's new state until the power button is pressed again. It's a steady state - the main power supply is on as long as the PS_ON signal is high.

There are a number of things that can be checked if the PS_ON signal does not change state. The first is obvious - the cable from the control panel to the signal board.

The next is the LDO regulators on the signal board - there are usually at least two of them.

The third is the input connector for the cable from the control panel - make sure signal from the power button is making it's way to the controller.

PlainBill

[pacmanretro]

Re: Spectroniq PLTV-3250 wont start

So got some parts in and replaced caps and Q7. I now have my 5V standby, but unit is still dead...

My understanding is that the 3.3VDC signal voltage is a brief voltage sent back to the power supply when the power button is pressed enabling the turn on of the 16 snd 24vdc section; correct?

So whether using the power button or remote, I should be able to meter the signal voltage. If it does appear, I need to check things like Q11.

Anyone have any idea what to look for if I have the 5VDC standby, but can't get it to send back the 3.3VDC for turn on?

Thanks!!