HP1955 Board Burnout - Is it Fixable?

[harveywilson]

Re: HP1955 Board Burnout - Is it Fixable?

I purchased a transistor replacement kit from eBay for a few dollars and today replaced the damaged parts. I'm pleased to report that the monitor is now up and running, and not smoking (yet!).

Thanks to all that took the time to offer advice in this thread.

[retiredcaps]

Re: HP1955 Board Burnout - Is it Fixable?

I purchased a transistor replacement kit from eBay for a few dollars and today replaced the damaged parts. I'm pleased to report that the monitor is now up and running, and not smoking (yet!).

Good job. Hopefully you resoldered the all transformer pins?

[seanc]

Re: HP1955 Board Burnout - Is it Fixable?

Can you tell us what parts you replaced?
Part numbers & locations?

[Jox-CZ]

Re: HP1955 Board Burnout - Is it Fixable?

Hello all,

I saved this monitor, my colleague want throw it to electro waste

In my case was burned only one side of the backlight circuit.

I renew these parts:

2xQ808&Q809 - [Original C5707] replacement: 2SC5707
1xQ805 - [Original J598] replacement: IRFU9024n
1xQ804 - [Original-SMD t06 - PMBS3906] replacement: BC857B

The monitor is like new.
Only the replacement IRFU9024n has a higher RDS.
It cause there is higher temperature on the 9024.
J598 - 45°C x IRFU9024n - 55°C
I hope it isn't problem

So, I thank you for the advices in this thread ;-)

Some photos: ==>

[selldoor]

Re: HP1955 Board Burnout - Is it Fixable?

Well done !

I hope you took note of the advice about re soldering the transformers.
Its best to remove the old solder and resolder each pin. Do the same for the blue capacitors and for the other c5707s
We have had many members who didnt do this and had to return a few days
later as the 5707s just replaced had blown again.
It is the bad solder on these boards that causes the problems

[Jox-CZ]

Re: HP1955 Board Burnout - Is it Fixable?

With the transformers it's a different story
We have in the work one same monitor HP1955,
but it made horrible whistling sounds.
So I changed the transformer from the burned board.
There is some differences between the boards. Here you can see =>

The result is, that no monitor don't whistling.

I have the desoldering tool HAKO484so it was piece of cake ;-)