Barco 800 problem shutingdown

[Stargatefour]

Hi !

Have a problem with my BG800.
Picture great, mint tubes in this one..

But the problem that have come last week is folowing .

when i shut it down to standby. The tubes display a bright dot in screen.
about 4*4 inch . on a 100 inch screen.

Some have told me that the FET on amplifier boards are bad.

But it seems a bid stange that all 3 going bad same time.
( have ordered new ones to change them all)

The powersupply is resoldered to.

Some one have seen this problem ?

Best way to narrow down this fault ?

Roland help me ! please.

Scared to power this one upp again.

Thanks for help .

Best regards STG4

[cosaw]

I'd be weary about powering up again till you've got the advice of the pros or checked your tubes for spot burn - don't wanna ruin those mint tubes. I beleive the bright dot can be very bad for your tubes if its intense.

I'm in a similar situation at the mo - good tubes unstable picture but no bright spot. Seems to be a fault on horizontal deflection board on mine as the red voltage "hold down led" is lighting. I also had suspicions about the fets but my electronics knowledge is limited.

By the way where did you order your mosfets from? How many and what price? Thought I'd read they're difficult to get hold of the actual ones.

Hope it works out!

Simon

[Stargatefour]

So noone have a clue about this ?? someone must have seen something like this.

il gues il have to wait for those fet.

someone please tell me the best way to disconect the tubes, so im able to only run the red, atleast it will only be one that will be toasted then.

hope for the best.

best regards STG4

[PsychoDogBeast]

Hi there

As cosaw says, i'd be very wary about turning this unit on as it sounds like you might spot kill your tubes, has the projector had the power supply resoldered in its life time yet, as far as i know if it hasn't this could be the source of your problem.

Speak to Roland he will know better, i'd be tempted to take your lenses off and inspect the tubes as well, just to make sure your tubes are ok.

James

[Stargatefour]

hi,

I think they are safe, the spot is quite big now. but eventualy they will probably be toasted .

il try to figure out how to run only one tube, have a spare red to test on.

i will not power all up again before i know its safe. hopefully changing the fet will help. the powersupply is resoldered .

Im quite new to this, but at least i figure out that it must be some card thats kills the beam before going to standby, and obvesly it not working probably,

hopefully Roland will arive and save me . :-)

thanks for your consern crt lovers.

(hmm if only the fet could arive now, so eager to run some games again on my lovely Barco)

/STG4

[bxd]

Hi,

There are some mods that can be done to the G800 to cure the spot problem and Roland should have some details of it.

Also, have a look at www.lynxxx.nl/barco/default.asp

Brian

[Stargatefour]

Fet's arived today .

I put them in . Fired the baby up,

and... to standby. ..

Spots nowhere to be seen !! nice!!

and the a tint of red in black is also gone .

now its working proparly again .

Cu all crt lovers

[klr10]

Hee Hee!! Well done... I love it when a plan comes together!!

Knowledge is POWER!!!!