Hitachi TV - Dry Joint Problem - Is This DIYable?

[Whitespirit66]

I have a 9 year old 28" widescreen Hitachi TV, which usually works really well, but has a small fault.

The TV is difficult to start when you turn it on, it starts but cuts out again. It keeps flashing on and off until eventually the picture stays on and all is well. To make it start quicker, a tap (in the time honoured tradition!) on the top of the TV seems to help what is obviously a looase connection. It must be getting worse, as its getting more difficult to start.

A TV shop diagnosed it as a 'dry joint' over the phone, and quoted £75. What I want to know, does this mean its only a poor soldered connection thats the problem? Can I fix it with my soldering iron? If it is a dry joint, will I be able to find it easily, ie will the connection be discoloured (its been going on for a few years)?

Many thanks

 

[ban-all-sheds]

What I want to know, does this mean its only a poor soldered connection thats the problem?

Probably.

Can I fix it with my soldering iron?

I don't see how anybody here can know that.

If it is a dry joint, will I be able to find it easily,

ie will the connection be discoloured

Probably not.

Also, are you happy that you'll be able to safely work inside the TV with it powered on? You're going to have to wiggle and flex things to home in on the fault.

Is it a CRT?

 

[gday2uk]

Is it a CRT?

Did we have plasma/lcd 9 years ago?

 

[ban-all-sheds]

Dunno - can't remember.

 

[dave-lew99]

We did, but they were so expensive the OP's is likely to be CRT.

Finding the joint will be difficult at best, you'll also need very steady hands and a fine tip temperature controlled iron to do a proper job.

£75 is a reasonable sort of price, but really i wouldn't bother as once one part starts to go the rest is probably on it's way out and you're just buying time.

9 years is a good run for modern brown goods (not like the good old days - the TV I had when i lived with my parents is now 23 years old and still going strong).

You really have three options

1: Pay for the repair and wait until it breaks again

2: Buy a second hand CRT widescreen, they are available literally for peanuts from car boots/ebay/classifieds

3: Bite the bullet and get a nice shiny new telly - a reasonable 32" LCD will set you back about £350 these days. - probably less than what you paid for the CRT!

 

[bathjobby]

Also, are you happy that you'll be able to safely work inside the TV with it powered on?

Don't be fooled; are you also happy to work inside the TV with it powered off, all those bloody big capacitors inside..... and if you avoid those for your own safety, are you going to be earthed so that you don't hurt the delicates !
If your not sure of what we are saying, pay your £75 or upgrade.

 

[mattylad]

Myself I'd be straight in there...

After some research online to find if it is a common fault on that model.

Leaving it switched off for a few hours should enable the caps etc to drain down.

Then (perhaps marking the connectors if you have to remove them - so they go back in the right place) have a gander at the bottom of the board.

Around the HT transformer is common for dry joints.

Although this may well be on the mains side, perhaps around the on/off switch as that gets more mechanical abuse.

The dry joint should have a ring around the joint, google for pics of what they look like.

Be extremely careful soldering it if you find it & make damn sure the TV is not plugged in when you solder it.

Always remember to stick on hand in your pocket if your working inside a powered TV.

 

[ban-all-sheds]

Always remember to stick on hand in your pocket if your working inside a powered TV.

That didn't help a friend of mine who once broke the hand he did have inside a telly when a tool caused an arc and he snatched his hand away so hard and so fast that he banged it against the top of the cabinet and fractured it...

There are some scarily high voltages present inside colour CRT TVs...

Whitespirit - do you have any ceramic or PTFE etc trimming tools? They can be useful for safely poking things.

 

[FourFootMedia]

Leaving it switched off for a few hours should enable the caps etc to drain down.

They can still pack a fair punch after being disconnected for over a year, saw someone get a fair old whack from a tube that hadn't been used for 16 months at a previous job.

 

[nitro23456]

It wouldnt be the same TV as one of these that you can get for the price of a pair of knickers on ebay?:

http://shop.ebay.co.uk/?_from=R40&_...&_nkw=28+hitachi+tv&_sacat=See-All-Categories

Save the £75.

 

[ban-all-sheds]

Some knickers on eBay go for quite a lot...