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Main => Monitor/Video Forum => Topic started by: Jack Burton on July 06, 2007, 11:50:25 am

Title: WG 25k7197 is emitting buzzing noise
Post by: Jack Burton on July 06, 2007, 11:50:25 am
Just yesterday I became the new owner of dedicated Mortal Kombat cabinet.  I was told everything was in working order, but when I tried to power on the machine, a high pitched buzz could be heard and I immediately shut it off. 

The sound was something between an air compressor and electricity.

I've disconnected everything and reduced the problem to being with the monitor.  Is this some kind of power issue?

Oh yeah, the model number is 25k7197
Title: Re: WG 25k7197 is emitting buzzing noise
Post by: SirPeale on July 06, 2007, 11:56:29 am
Power it on and watch the chassis.  Is it smoking?  Can you see any sparking anywhere?

I'd bet a dead flyback.
Title: Re: WG 25k7197 is emitting buzzing noise
Post by: grantspain on July 06, 2007, 12:21:24 pm
transported on its back?if you're lucky just the anode ht wire off,if you're unlucky the tube neck is broken
Title: Re: WG 25k7197 is emitting buzzing noise
Post by: Jack Burton on July 06, 2007, 12:40:09 pm
yes it was transported on it's back.

There is no smoke, or spark that I can see, though I've only turned it on twice, and only for about a second each time.

Where and what is the anode HT wire? 

Title: Re: WG 25k7197 is emitting buzzing noise
Post by: grantspain on July 06, 2007, 01:02:42 pm
the ht wire goes from the flyback transformer to the tube in the form of a suction cup(its a thick red wire)
Title: Re: WG 25k7197 is emitting buzzing noise
Post by: Jack Burton on July 06, 2007, 01:39:26 pm
I just checked and the anode ht is still plugged in securely.

I tried checking for sparks.  So I got into position to look at the monitor from behind while I flipped th power switch. 

There is electricity arcing between the halves of the transformer that the anode ht plugs into.  There is also a ground wire that is situated between them that connects to the chassis.  Is it supposed to be there?

Title: Re: WG 25k7197 is emitting buzzing noise
Post by: grantspain on July 06, 2007, 02:37:56 pm
if its arcing across the flyback transformer then there must a crack on the flyback itself,sounds like you need to replace that transformer(nice light show though)
Title: Re: WG 25k7197 is emitting buzzing noise
Post by: Jack Burton on July 06, 2007, 05:57:37 pm
So the monitor is probably still good?

What would you say the difficulty of replacing this transformer is?
Title: Re: WG 25k7197 is emitting buzzing noise
Post by: grantspain on July 06, 2007, 06:06:58 pm
for someone with experience maybe 30 mins to an hour,make sure you get the exact flyback-there will be some kind of label or embossing giving the flyback model code
don't attempt this yourself unless you do a lot of homework-there are some very nasty voltages just ready to zap you if you screw up
another option would be to disconnect the chassis and send for repair but once again you need to know what you are doing(e.g where every plug goes and how to discharge a tube safely) and another thing to remember is how delicate tube necks can be
Title: Re: WG 25k7197 is emitting buzzing noise
Post by: Jack Burton on July 06, 2007, 06:11:55 pm
Hmm, I think this is a little beyond my current capabilities.  I'm just getting into the whole cabinet making thing, and before I got this one had planned to build one myself and stick a cased computer monitor inside.

I would probably trade this whole monitor, power supply, jamma harness, and MK motherboard for a good TV to put in it.  Does that sound like a trade people would be interested in?

EDIT: That would also mean the trader would have to come and help me remove the components themselves.
Title: Re: WG 25k7197 is emitting buzzing noise
Post by: SirPeale on July 07, 2007, 03:47:11 am
Where are you located?
Title: Re: WG 25k7197 is emitting buzzing noise
Post by: Jack Burton on July 07, 2007, 09:07:22 am
Liberty, KY.

The TV has to have an infrared remote included so I can turn it on through the wood and glass.


EDIT:  I made a thread for this trade in the Buy/Trade forum.
Title: Re: WG 25k7197 is emitting buzzing noise
Post by: Jack Burton on October 28, 2007, 09:25:22 am
Ok, a little while later in life and I am now comfortable with discharging this monitor and working on this transformer.

A friend of mine who's in TV repair said that if the flyback has a crack in it it can be fixed with epoxy or glue or anything to to insulate the crack.  Does this sound possible to anyone here or has anyone used this method?
Title: Re: WG 25k7197 is emitting buzzing noise
Post by: Ken Layton on October 28, 2007, 12:41:43 pm
Clear silicone glue will work in some cases. However, the area must be cleaned first with household cleaner such as 409 then cleaned with isopropyl (rubbing) alcohol so the glue will stick.

Be advised if it's arcing that bad and you seal it up then it'll still probably crap out in a month. Might even explode too.