Gulp! My defender...

[MYX]

Of all the stupid things. My defender game was been having an ongoing issue that every so often, everything that should be black will flash to magenta. This innitially would only happen once and a while for a few seconds. Now it happens most of the time right at start up. I decided to open it up and reseat the video line and the decoder chips. Gulp. I was not paying attention and put the decoder chip in backwards. This would not be so bad has I not turned on the machine and heard SNAP and smelled the dreaded sulfer burn. I looked in the back of the machine to fine a little wisp of smoke wafting away from the chip. I feel sick even writing this.

Does anyone know where to get a replacement for these and does anyone have or know where I can find a board diagram to be positive which way it is supposed to go?

[forbiddenlyrics]

Here is the manual might be of some help.

http://www.klov.com/game_detail.php?letter=D&game_id=7547

[MYX]

Yeah, I have this one. It has a lot of info but not what I need. I have a Williams Black Knight Pinball and they have an awsome schematic section that shows the boards with ic and component placement w orientation. Very helpful. I also tried Mike's Arcade as he has a ton of schematics. his site says he has em but the link is not connective. I appreciate your help though!!!

[dabone]

Replace it with a 2732 eprom.


http://homearcade.org/BBBB/decoder.html


16 bucks plus shipping for a new pair.

Probally your cheapest way to get back up and running.

(And it's from Bob, so we know they come from a good seller)


Later,
dabone

[MYX]

Wow, I will give it a try. Unfortunatly it is Thanksgiving and most everybody is closed. I am also going to try the real Bob Roberts.

[skippy]

I bought a set from Bob about 6 months ago.  Also, IIRC he has a picture of the video board on his help pages that shows proper IC orientation

[RayB]

chips usually have a corner that's marked or "angled"...

[MYX]

After reading the page a couple times more and finally looking at the rest of the page, I realized that this WAS from the real Bob Roberts. Great!

[fredster]

I know how you feel.  I had a sound issue with my joust and it started rebooting itself.

I got it to work, except it still had this sound issue, by replacing the ram chips.

I got it to work pretty good and I had a couple left so I sez to meself, let's just go ahead and put these other two in..

I managed to get distracted, the #@@#! wouldn't go in easy, and I managed to get it in, but backwards.

When the machine fired, it didn't do anything.  It booted and then shutdown, etc.  Little led flashed and went out.

Well, I found the backward chip and went to pull it out, and buddy it was hot.

I managed to get it to come back up, but now there's no sound.  I'll have to replace all the freaking ram again.  I always get it from Bob Roberts.  I'm just going to replace all 24 ram chips like he told me the first time.

But if you try and fail, there's a guy on ebay that fixes them with great feedback - Link

You're out about $125.

I have a defender board I don't plan on fixing if that's a help.  I robbed some chips off of it, and it would be good for parts.  PM me if your interested, I'll let it go to a collector.  I will send you a pic if you want to make sure it has the chip, I can't remember offhand if it has all of the rom chips in it.