MP 42HC56 SINOTEC 42 lcd

[SonOfAnarchy ZA]

Re: MP 42HC56 SINOTEC 42 lcd

Reading the data sheet


This would indicate to me that there is a fault elsewhere which is switching off N501.

perhaps something else is in short i will have another look thanks

[dick_barton]

Re: MP 42HC56 SINOTEC 42 lcd

Reading the data sheet

A feedback voltage of 6V triggers overload protection (OLP).

This would indicate to me that there is a fault elsewhere which is switching off N501.

[SonOfAnarchy ZA]

Re: MP 42HC56 SINOTEC 42 lcd

What voltage do you have on pin 3 (Vfb) of N501

it goes from 0v to 9v then back to 0V and repeat

[dick_barton]

Re: MP 42HC56 SINOTEC 42 lcd

What voltage do you have on pin 3 (Vfb) of N501

[SonOfAnarchy ZA]

Re: MP 42HC56 SINOTEC 42 lcd

That diode provides the dc to give the V_15 (assume 15V) needed for a lot of the other IC's.
That seems awful low considering N501 requires VCC =12V min but has at least has 10V and if N502 has a 15V output then you would be expecting around 17.5V at it's input. Maybe worth checking C521.

i replaced the Cap replaced no change in voltage

[dick_barton]

Re: MP 42HC56 SINOTEC 42 lcd

That diode provides the dc to give the V_15 (assume 15V) needed for a lot of the other IC's.
That seems awful low considering N501 requires VCC =12V min but has at least has 10V and if N502 has a 15V output then you would be expecting around 17.5V at it's input. Maybe worth checking C521.

[SonOfAnarchy ZA]

Re: MP 42HC56 SINOTEC 42 lcd

If D502 had gone short then the Opto N506 may also have been damaged. I would certainly check it.

What DC voltage do you have on D505.

2vDC anode
0v cathode

n506 has been replaced

[dick_barton]

Re: MP 42HC56 SINOTEC 42 lcd

I replaced that cap with no luck. i found a 16v zener diode in short (D502) replaced it but no luck is it possible N501 is faulty?

If D502 had gone short then the Opto N506 may also have been damaged. I would certainly check it.

What DC voltage do you have on D505.

[SonOfAnarchy ZA]

Re: MP 42HC56 SINOTEC 42 lcd

check r597 r598.
thats your startup source.
what voltage do you have pin 2 and 5 of n501?

Pin 2 Has 10VDC
Pin 5 Has 184VDC

R597 and R598 measure 68kOhm according to the circuit diagram they should be 47KOhm

[kc8adu]

Re: MP 42HC56 SINOTEC 42 lcd

check r597 r598.
thats your startup source.
what voltage do you have pin 2 and 5 of n501?

[SonOfAnarchy ZA]

Re: MP 42HC56 SINOTEC 42 lcd

Is this Power supply the exact same one as posted in the picture of my thread?

Having blown zeners sounds more that this TV had a direct lightning strike.

I have been unsuccessful to source the correct chip located at N501 and only found similar ones that works but not in the way intended , hence my discovery of the cap that caused it to not switch on..
My last resort was to build a power supply, to supply power the other 2 that this 1 starts up..

FSQ110 versus the( FSL206 this particular chip works in a pulse mode effect) RS is closer to you as you are in JHB.. order this and try it in the old N501's place.. At least it would give you a good idea what to look for.....as it does work without any mods.

Otherwise suppliers they still have stock of this TV's PSU and CFL driver boards checked 2 months ago..

which supplier did you contact? i have received the correct parts with no luck still dead as a door knob

[SonOfAnarchy ZA]

Re: MP 42HC56 SINOTEC 42 lcd

Yes it is the exact power supply. i Have ordered that specific chip from China will let you know if it works out

[battlecat]

Re: MP 42HC56 SINOTEC 42 lcd

Is this Power supply the exact same one as posted in the picture of my thread?

Having blown zeners sounds more that this TV had a direct lightning strike.

I have been unsuccessful to source the correct chip located at N501 and only found similar ones that works but not in the way intended , hence my discovery of the cap that caused it to not switch on..
My last resort was to build a power supply, to supply power the other 2 that this 1 starts up..

FSQ110 versus the( FSL206 this particular chip works in a pulse mode effect) RS is closer to you as you are in JHB.. order this and try it in the old N501's place.. At least it would give you a good idea what to look for.....as it does work without any mods.

Otherwise suppliers they still have stock of this TV's PSU and CFL driver boards checked 2 months ago..

[SonOfAnarchy ZA]

Re: MP 42HC56 SINOTEC 42 lcd

Hi , check the small electrolyitic cap next to the N105... sit close to pin 1

DON"t even check it just replace it.. with exactly the same value.. anything higher or lower messed me around..

That will switch on the chip.

Also watch out for the HT boards on this tv Master & Slave...


FSL206MR that I bought was actually totally wrong

I replaced that cap with no luck. i found a 16v zener diode in short (D502) replaced it but no luck is it possible N501 is faulty?

[battlecat]

Re: MP 42HC56 SINOTEC 42 lcd

Hi , check the small electrolyitic cap next to the N105... sit close to pin 1

DON"t even check it just replace it.. with exactly the same value.. anything higher or lower messed me around..

That will switch on the chip.

Also watch out for the HT boards on this tv Master & Slave...


FSL206MR that I bought was actually totally wrong

[SonOfAnarchy ZA]

Re: MP 42HC56 SINOTEC 42 lcd

and 280vDC across the two filter caps

[SonOfAnarchy ZA]

Re: MP 42HC56 SINOTEC 42 lcd

I have 7vDC on N105

[SonOfAnarchy ZA]

Re: MP 42HC56 SINOTEC 42 lcd

Hi guys. Sorry to revive this old thread I''ve also got the same supply and it died as well. blown fuse and D506 was dead short everything else seems to measure correctly I cant seem to find that specific diode but put in a fast recovery diode with similar specifications but the supply is still stone dead I suspect N507 (l6563) to be faulty but not sure was the problem ever resolved on this fault?

[battlecat]

Re: MP 42HC56 SINOTEC 42 lcd

HERE is the really bad news .....




No idea how did manufacturers still went ahead and use these devices if this was happening

[battlecat]

Re: MP 42HC56 SINOTEC 42 lcd

OK so here is a bummer the FSQ110 from Fairchild is discontinued ...grrrrr...
Had a look at their datasheets ""with my extremely slow internet connection""

Followed the ""rabbit "" and pointed me to the FSL206MR which I ordered via RS-Online... and seem there is a couple of light mods needed to get this chap working in there...

Seem I don't get any voltage on pin 1 and 2 like BUDM mentioned .. not even with the FSL206 in place ...pin 5 is the point to which the cap at pin 2 and 1 get charged up to switch on the Ic N501.. ( maybe some experimenting with the resistor values at pin 5)

Would it be possible if someone could maybe check up on the FSQ110 versus the FSL206 if I made the right choice there?

Thanks for the advice and replies thus far