RE: Asteroids - Loud Humming?

Sometimes a bad LM324 will hum and sound like a bad filter cap.

Bill

-----Original Message-----
From: owner-vectorlist@vectorlist.org
[mailto:owner-vectorlist@vectorlist.org] On Behalf Of Darren Finck
Sent: Sunday, June 27, 2010 6:20 PM
To: vectorlist@vectorlist.org
Subject: RE: VECTOR: Asteroids - Loud Humming?

No soldering is required. See this thread:
http://forums.arcade-museum.com/showthread.php?t=32921

The caps themselves are not available just anywhere. I know The Real Bob
Roberts sells them, as does Mark Capps (arcadechips.com), and perhaps a few
others.

All that said, Big Blue may or may not be the problem (although, if it's
original it should likely be replaced). Where is the humm eminating from?
The speaker? The transformer? The monitor? If it were my game, I'd
disconnect everything and check function component-by-component up the line.
Start with just the power brick, verify all voltage outputs. Add AR board,
verify those voltages. Only then connect the logic board and/or monitor.

Darren

--- On Sun, 6/27/10, Shawn Muller <shawnmuller@earthlink.net> wrote:

> From: Shawn Muller <shawnmuller@earthlink.net>
> Subject: RE: VECTOR: Asteroids - Loud Humming?
> To: vectorlist@vectorlist.org
> Date: Sunday, June 27, 2010, 7:07 PM
> I'm in the Kansas City area. If I
> know the steps and know that I have the correct part, then
> it doesn't bother me to get my hands a little dirty. But,
> once soldering comes into play that's when I defer to
> someone with more expertise.
>
>
> -----Original Message-----
> >From: "Matt J. McCullar" <mccullar@flash.net>
> >Sent: Jun 27, 2010 6:33 PM
> >To: vectorlist@vectorlist.org
> >Subject: RE: VECTOR: Asteroids - Loud Humming?
> >
> >That is usually the problem.  After 30 years, it's
> not unusual for "Big Blue" (as that big filter capacitor is
> often called) to fail, and it allows AC ripple to get into
> the DC power supply.  In fact, it's not a good idea to
> leave the game on long in this condition, as it may damage
> the motherboard. 
> >
> >As for whether or not you can replace it yourself,
> well... that depends on your expertise.  We all gotta
> start somewhere.  That "Big Blue" can be easily
> replaced, but you must know exactly what you are
> doing.  Take careful notes as you go, take photos if
> you can.  Keep track of what goes where.  (Don't
> put it in backwards!)  If you don't want to tackle this
> yourself, just state where you're located and see if anyone
> on the list is close by and can handle it personally.
> >
> >Matt J. McCullar
> >Arlington, TX
> >*********************************
> >
> >
> >-----Original Message-----
> >From: owner-vectorlist@vectorlist.org
> >[mailto:owner-vectorlist@vectorlist.org]On
> Behalf Of Shawn Muller
> >Sent: Sunday, June 27, 2010 5:08 PM
> >To: vectorlist@vectorlist.org
> >Subject: VECTOR: Asteroids - Loud Humming?
> >
> >
> >I just picked up an Asteroids machine that was supposed
> to be in good working condition...not quite the case as I've
> discovered!
> >
> >The main issue at the moment is that the machine
> produces a very loud very annoying humming. Any thoughts as
> to where to start on repair? I read somewhere that the big
> capacitor on the power brick is the likely culprit. Is that
> true? If so, is there any inherent danger in replacing it
> myself? Should I be looking at a different starting
> solution?
> >
> >
>
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> >
>
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>
>
>
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Received on Sun Jun 27 21:03:30 2010