Monitor cracklin' and ratlin'

[ArtMAME]

I just finished moving a NeoGeo game into my gameroom.  I had to go over a door way and it came down a bit rough down off the threshold.  It was working fine before I moved it, but now when I power it up, I heard some rapid crackling.  I opened it up and tried it again and I saw some rapid arcing on the power connector to the monitor.  I removed the power connector from the monitor and the game powers up fine with no cracklin.

Did I just mess up my monitor?  Or could it be something with the B+ voltage?  Or could I have possibly cracked the tube?

Sorry, don't know the make and model. It is a 25".  Hard to see the chassis because of the way it is mounted in the cabinet.  Probably a Wells???

Any advice would be apreciated.  Thanks.

[FrizzleFried]

By power connector,  do you mean the power going to the chassis or the anode wire going from the chassis to the tube? (with the suction cup looking cap at the end).

[ArtMAME]

The plastic molex connector that supplies 120VAC to the chassis.  I can see some sparking inside the connector when I power it up.  The sparking is fast and continiuous, kind of like a machine gun.

[SirPeale]

Try reseating that connector and try again.

[ArtMAME]

Yes, unplugged then re-plugged it at the molex connector, same results...

[FrizzleFried]

Is there any noticeable damage to the connector?   It's real easy to cut `em off and wire-nut the two wires together...

[Ken Layton]

Actually, I bet the female connectors pins are spread too wide. The male pins are too loose inside the female pins.

The cure is to replace the male and female pins both.

[ArtMAME]

Yes, I can wire-nut'em to see if they power up the monitor.  If they do, I will replace the molex connector.

Thanks.

[ArtMAME]

Replaced the female pins on the molex connector, same result.

Cut off the molexes and wire nutted the wires, still same result.

Can not see the sparking at the molex anymore, because there is no molex anymore.  Smells kinda like gunpower after I turned it on and off again.

It is a Wells 25K7191 after all. 

Could be a pin-hole in the insulation between the Hot and neutral wires?

Or could it be a cold solder joint?

Any ideas?

[grantspain]

i expect you have a very bad solder joint on the a/c input plug,that smell of gunpowder is where the circuit board has burnt.
you may need to solder your a/c wires direct to the track a little further back from the damaged area(either to the next available solder point or you could scrape the track and solder to that)
whatever it is you will need to unbolt the chassis and look underneath,no need to discharge just don't do it with it plugged in and be careful of the neck

[ArtMAME]

I unbolted the chassis, did not see any apparent damage.  Reflowed the solder on the AC leads to the board and tried it again.  Same result.

[ArtMAME]

OK... thought I would fire it up one more time before I sent it off to Tom (a local repairman who is good friends with one of my co-workers) for a repair...

Powered up... no more cracklin', but some kind of sound, like burning hair or something... turned it off and looked in the back... SMOKE!!!

And more smell, like gunpowder, but different this time...

Could this be a bad flyback??? 

[Ken Layton]

Flyback probably has pinholes or hairline cracks in it. These pinholes sometimes happen underneath the flyback where you can't see them. Sounds like you may be getting in over your head and it's a good idea to send the chassis off for repair. And be sure to replace those Molex connectors so everything is back to normal again.