Vs. unisystem monitor is buzzing...is this normal?

[2PacMan]

I recently purchased a vs. Super Mario Bros in a Nintendo vs. unisystem cabinet and i can hear a buzzing coming from the back of the monitor.  It is also coming out of the speaker in the front of the game.  It is noticable when the game is in attract mode, but once the game starts and the music plays, it's not really noticeable.  Is this normal?  Is there something i can do to fix this?  I remember reading a post about removing some sort of cage?  Does this ring a bell?  I don't know anything about these monitors.  I don't know what type it is, but i'm sure it's the one that was in all the vs. cabinets, the one with the reverse color, the unique monitors that work in the vs. systems only.  It does have a section of it in a metal casing.  It doesn't sound like vibration though, it sounds more like a speaker hum or the glowing of the neckboard, but i believe it's louder than it should be.  It's not a high pitched hum or squeal, but more of a buzzing noise.

[grantspain]

If you disconnect the speakers is the hum still there?if so you could be looking at a noisy coil,even a transformer-you should be able to locate it by tapping very lightly where the noise is coming from with something  insulated-cheaper monitors suffered this problem,its more an annoyance than a fault.

[2PacMan]

Well, i took your advice and disconnected the speaker.  It's not the monitor at all, it's the definately the speaker making the buzzing noise....now what??  Anyone know how to fix this....i suppose i should post this in a different forum now that it's not monitor related anymore.

[Ken Layton]

All Nintendo cabinets use either a Sanyo 20-EZ or Sharp XM-2001 special monitor. They all have the sound amplifier built into the monitor.

Chances are yours has a Sanyo monitor and both the sound amplifier board and the monitor main board need capkits. Bob Roberts sells those.

[2PacMan]

Thanks, glad to know it's not the speaker.....a cap kit is way above my capabilities, so i guess i'll just have to live with it.  Thanks!

Ken...didn't one time in a previous post you mention something about removing a metal cage from the monitor to prevent overheating in the nintendo cabs??  Does that ring a bell?  If so, should i do it?  It's not on very long at a time, only for home use.  This wouldn't have any effect on the buzzing, would it?

[clanggedin]

If your cab has a Sanyo 20EZ in it then remove the cage that surrounds the flyback. After I capped my monitors I removed that cage too. Appparently you can't buy the flybacks anymore.

[Ken Layton]

The flyback cage on the SHARP monitors should be removed so the flyback can stay cool. Don't remove the cage on a SANYO monitor though.

Flybacks are NOT available for the SHARP monitors.

Reproduction flybacks ARE available for the SANYO.

[grantspain]

I have never seen a cab that uses the monitor to amp the sound,is this something you get only in the states?
Def sounds like cap fault
Why cant you use an external amp and bypass the monitor or is this something really obscure.
every machine i have ever worked on(even if it has no onboard amp on the game pcb) has a left/right sound output that goes straight to the speakers or to a op amp pcb(especially williams),surely you could bypass the monitor completly and goto something like a car stereo amp.
You do have some strange machines in the U.S!