2 dead monitors, blueh h94w and amw x1700ds

[flosers]

Re: 2 dead monitors, blueh h94w and amw x1700ds

Well I prefer don't do that that is not a a permanent fix.

[selldoor]

Re: 2 dead monitors, blueh h94w and amw x1700ds

OK - how about soldering a jumper in place just to see if it works?
That would help in deciding what is working and what is not.
Whatever happens if you use a wire jumper it could easily be removed.

[flosers]

Re: 2 dead monitors, blueh h94w and amw x1700ds

Nothing on the screen.

[selldoor]

Re: 2 dead monitors, blueh h94w and amw x1700ds

Ok - did you have a working pc connected did lights flash?

[flosers]

Re: 2 dead monitors, blueh h94w and amw x1700ds

Nothing,no light flash.
The led still green so the monitor recognize the source. (a working pc of course).

[selldoor]

Re: 2 dead monitors, blueh h94w and amw x1700ds

Just noticed on your jumper picture just above the jumper there are 2 zero rated resistors
R514 and R510 - can you test those as if they were a fuse. (no Power to board)

[flosers]

Re: 2 dead monitors, blueh h94w and amw x1700ds

I have 0.003 with the multimeter on 200ohm on the two resistor.

[selldoor]

Re: 2 dead monitors, blueh h94w and amw x1700ds

Pity - I am out of ideas - no one else is joining in either.

[stj]

Re: 2 dead monitors, blueh h94w and amw x1700ds

i will start by saying i only read the last post - and the first!

on the blue monitor you say that after a while the 5v drops to 4.6 but with a seperate supply it works.

did you try replacing the rectifier diode on the psu 5v line?

[flosers]

Re: 2 dead monitors, blueh h94w and amw x1700ds

In fact I am am not the beginner of this post. I have the same problem for the h94 there is a problem in the inverter section. I'm pretty sure of that because I have test my monitor with an external inverter and its work. (the inverter have just one output but I have test the four lamp one by one during five minute and they work)
I hope you have an idea
Thanks in advance

[stj]

Re: 2 dead monitors, blueh h94w and amw x1700ds

@flosers
post foto's of your invertor

[flosers]

Re: 2 dead monitors, blueh h94w and amw x1700ds

It is an inverter from a lcd controler like this: http://m.ebay.fr/itm?itemId=271505174443

[stj]

Re: 2 dead monitors, blueh h94w and amw x1700ds

that wont help me spot a problem.
it has to be your invertor

[selldoor]

Re: 2 dead monitors, blueh h94w and amw x1700ds

stj - he is French so whilst English is good he doesnt always follow unless it is spelled out.
He has two inverters mentioned - the one in the set and the "test" one which he has used to verify that each bulb will stay on for 5 minutes - so I reckon that proves they are ok.
The set inverter is on the power supply and pictures are in earlier post (transferred from
his offsite)
https://www.badcaps.net/forum/showpo...1&postcount=43

Hope you can spot something I am out of ideas.

[stj]

Re: 2 dead monitors, blueh h94w and amw x1700ds

is the test one he same type?
if it's for a larger tube it could run where the original will trip in an overcurrent condition.

i mean, why cant he just fit the test invertor & use the monitor fully?

[selldoor]

Re: 2 dead monitors, blueh h94w and amw x1700ds

is the test one he same type?
if it's for a larger tube it could run where the original will trip in an overcurrent condition.

i mean, why cant he just fit the test invertor & use the monitor fully?

Take your point - we did try shorting out the timer on the driverIC to give the lamps longer to come on but it didnt work

Test inverter has only one connector - when he uses it he can see a picture.
so he could get a cheap 4 connector inverter and wire that in somehow.

[stj]

Re: 2 dead monitors, blueh h94w and amw x1700ds

o.k. i read all the thread now.

possible causes:
tubes drawing too much current because they are very old.
this can be checked visually if he wants to pull them out.
or
transformer/fet/driver breaking down under load.

replacing the tubes is a gamble,
replacing the board is a gamble.

if it was me, i'd bin the tubes,transformers,fets & driver i.c. and fit an led kit.
it just bypasses everything that could go wrong in a single move for about 15Euro

[flosers]

Re: 2 dead monitors, blueh h94w and amw x1700ds

Ok thanks for your help for the moment I have buy an external inverter with 4 connector:
http://cgi.ebay.fr/ws/eBayISAPI.dll?...84.m1497.l2649
I just need to found 12v in PSU board and the problem will be normally resolve.
Against thank's for your help!
Edit:
I just remember that I have test the PSU board with a laptop,I have conected CCFL of the laptop screen to the PSU and I had the same problem so the problem seem to don't come from CCFL?

[stj]

Re: 2 dead monitors, blueh h94w and amw x1700ds

you cant test a 19inch cfl with a laptop invertor

[selldoor]

Re: 2 dead monitors, blueh h94w and amw x1700ds

you cant test a 19inch cfl with a laptop invertor

Maybe not but I dont think that is what he said.?
He was trying to light the laptop ccfl with the monitor inverter.
( Before you say it I know you dont think that is a valid test as the bulbs are smaller) BUT that didnt work either giving more support to the idea it is a
problem with the inverter circuit - anyway a 4way inverter will give us the answer.