Re: Here's how I fixed Sound prob. on Midway Space Invaders

On Jun 8, 7:28 am, "edward.lutz" <edward.l...@xxxxxxxxxxxxx> wrote:
No, you do not program it. It's basically a tiny amplifier. Be careful when
you remove the old one. It's real easy to tear up the traces on those old
Midway boards. Any decent electronic supply house should have it...or a
cross. This isn't something you'll be able to pick up at Radio Shack.

Edward"RRcade" <jaschebr...@xxxxxxxxx> wrote in message

news:1181271091.036577.136060@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx



On Jun 7, 9:47 am, "edward.lutz" <edward.l...@xxxxxxxxxxxxx> wrote:
Try replacing the LM3900 beside the volume control.

Edward"RRcade" <jaschebr...@xxxxxxxxx> wrote in message

news:1181211586.635197.78770@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

My Midway SI was working all the way except No sound at all, I assumed
Sound Board, I was wrong. I had 3 Power boards that I assumed where
bad(jubbled video displayed),after adjusting the boards I got perfect
video and game played great, but still no sound. I started poking
around one of the Power boards with a multimeter and found a bad
diode, I replaced it and voila game works 100% Sound and Picture. So
without testing the other Power boards I just went and changed out
that diode on the others and it fixed all of them. So if your game
plays and you have NO sound try replacing the single IN4004 Diode
directly below the cable connector. Now my only problem is volume, I
tested my 50k pot and it goes 0 to about 44, the volume is Way lower
than the max. should be, what should I try to get more volume?
Thanks- Hide quoted text -

- Show quoted text -
Does the LM3900 your refering to have to be programmed? Do you know
where I could get one?
Thanks, I've heard that might fix it.- Hide quoted text -

- Show quoted text -

or a cross? what's a cross? Also I've heard people mention piggy
backing, is that what it sounds like-soldering one chip on top of
another? Is that safe to do in all applications where you don't want
to chance lifting pads/traces?
Thanks for the info

.

Loading