HannSpree JT01-32E1-000G help identifying and ordering part

[gidi19]

Hi all.

I am a complete noobie and have been trying to fix my TV. One day it went completley dead. No power whatsoever. I've changed the fuse in the plug.Nothing. I then opened the unit and changed the fuse on the power board. Nothing happened. I done some research and found out about bad capacitors. De-soldered the capacitors on the board and went to maplins for replacements. After putting in new capacitors and making sure the polarity was the right way round plugged it in and still no power.
I have a multimeter but can't understand how to use it properly.
After alot of reading I have found a pdf which shows how to repair psu. Problem is I have no idea what the part is or where to order it from. If someone could point me in the right direction. I dont want to spend too much money behind it so cheap and chearful.
My next step is to replace these parts, it's all hit and hope at the moment. If someone could guide me on what to do next I would be grateful. I have attached a pic of my board with new caps on it. Photo is not great but if some one could point me in the right direction I couold move furthur.
I'm trying to understand how to test the PSU but if someone could tell me exactly what to do (put) on my multimeter and where to stick the probe.(something bout black to ground or board and red to pins but i dont know which pins)
Apologies for sounding extremely useless, but for some reason i am finding this journey quite relaxing. Will be happy if i bring it back to life.

[paulstef]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

You mean you have the service manual for that TV with a schematic of the PSU?

The circled components in the picture are resistors, a diode and the one with the 3 pins could be a lot of things, diodes, transistors, voltage reference. If you are not sure that they are faulty there is no point in replacing them.

First of all, when measuring anything in the PSU while it's powered on, make sure you don't hurt yourself, apart from the obviously dangerous input AC voltage there are also the big caps on the primary side which even after you remove the AC voltage can hold some charge for a while. They are typically labelled blabla uF and then 350V or 400V. After removing AC power wait some time before measuring anything inside the PSU. To be sure measure the residual voltage on the caps (from + to - directly).

[gidi19]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

Would i be able to buy them from maplins or will i have to order them from somewhere? I have a feeling that it might be the problem.

[paulstef]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

Well, no.

You won't be able to order anything until you identified the parts. And I'm sorry to tell you but you don't troubleshoot out of a feeling.

Why do you have the feeling that they might be damaged?

If you have a circuit diagram then post it here please. And post the document you took the pictures from.

[flocko]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

The words Maplin and buying capacitor should not go together, we know they sell them but they are the wrong type to be fitting in a Tv power supply, and could be why it will not work, you need to obtain low esr capacitors look though the forum for were to buy and the best makes Flocko

[tom66]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

Exactly, maplin capacitors are terrible. Best to mail order them. CPC has free delivery on any order and they stock Panasonic FR, FM and FC series which are good replacements.

[paulstef]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

The words Maplin and buying capacitor should not go together, we know they sell them but they are the wrong type to be fitting in a Tv power supply, and could be why it will not work, you need to obtain low esr capacitors look though the forum for were to buy and the best makes Flocko

While it's better to use the correct caps for each application I say the OPs PSU would show at least some signs of life if the caps had been faulty. His PSU is dead.

[tom66]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

I'd normally agree with you if it weren't for having the occasional PSU with wrong capacitors in it acting dead. E.G. low standby voltage.

[paulstef]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

@gidi19

I encourage everybody to try to repair their electronics and learn something from it. Too much is thrown away.

But a TV PSU is not a beginner project. Changing parts with a shotgun approach is counterproductive, you don't learn anything AND you can spend much more money than you wanted.

[paulstef]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

Is this the document you have?

Is there a label on the PSU? What does it say?

Please post a complete picture of the PSU board and then a picture of any labels.

What multimeter do you have?

[gidi19]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

Hi,

I've attached the pdf file that i found and keep referring too.

I have a basic yellow multimeter.(attached photo)

I'm at work now, once i get home i will take more photos of the board and upload photos.

on a side note i went and bought another Hannspree tv, same make and model with same problem and tried capacitors on second board too. Same symptoms. Plus side i've got two tvs that dont work, but if i blow one up i always have a back up ready.

[paulstef]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

You will mainly use what I marked in the picture.

DC voltage measurement, used for almost all voltage measurements we may ask you to do

AC voltage measurement, you can check the input AC voltage up the main rectifiers with this

Resistor measurement, can be used in circuit to verify some components under certain circumstances, to be sure you may have to remove some components to reliably measure them

Diode check, will show the voltage drop on any components with diode behaviour, you can check with this diodes, bipolar transistors, Mosfet body diodes

When doing DC voltage measurements: If the display reads a positive value the voltage at the red probe is positive with respect to the voltage at the black probe.

Don't forget: When doing passive measurements (resistor, diode check) turn off power and wait until the main caps are discharged. Check their DC voltage before proceeding!

[paulstef]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

Your repair procedure is related to a repair kit sold by who?

It doesn't say what the small components to be replaced are. You can at least check them with multimeter. Take a high res picture of the circled components so we can see what's printed on and around them.

[budm]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

Can we see good clear pictures of both sides of YOUR board?

[gidi19]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

Hi,

I've tried to take as many good photos as i can.

[gidi19]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

Let me know if you need more pics

[paulstef]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

Yes, R65 looks indeed as if it has a hole in it. That would be a 5.1 Ohm resistor.
Then they recommend replacing Q7, R58 (5.1kOhm) and ZD4.

Q7 is a transistor, ZD4 a zener diode.

If this is a common fault for this model you should find the repair kit related to the document you found. Where did you find it?

Otherwise we need a picture to see what's printed on Q7 and even then it could be difficult to find out what it is.

[paulstef]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

You can do the following checks:

multimeter in diode check mode. red probe on the zener diode opposite side of the black ring, black probe on the side where the black ring is. What does it read?

multimeter in resistor mode , range 200 Ohm. one of the probe on one side of the resistor R65, the other one on the other side. What does it read?

[budm]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

This is how I repair the commonly failed Q7, ZD4.
http://s807.photobucket.com/user/bud...?sort=3&page=1

[paulstef]

Re: HannSpree JT01-32E1-000G help identifying and ordering part

Well, a schematic makes it all easier. :-)

Thanks BudM.

gidi19, there you have it:

zener diode 15V (low wattage is ok)
resistor 5.1k
resistor 5.1R (not sure about the wattage, voltage goes everywhere, use same size, 1206 or 0805, have to measure its dimensions to be sure)
transistor MMBT4401 or similar, bud used 2n2222