Pole Position bad sprites

[scotthh]

I recently picked up a Pole Position.

The car sprites aren't showing up in the bottom 1/3 of the screen. According to the Service manual the "large car pictures" come from Custom IC 12J and 13J. I ran the self-test, and it says everything is fine. I checked those two chips which are in sockets, and they don't show any visual signs of damage and appear to be seated properly. Any ideas? Thanks!



Other things I think are important:

• Someone put a switching power supply in the machine along the way, it powers the boards.
• I need to redo the edge connectors. They have some burn marks and solder repairs.
• The picture is from another monitor. The Hantarex 900E that came in the Pole Position is getting 120v from the power supply, but is showing no signs of life. After I get the car sprites working, this is my next big issue to fix.

[HaRuMaN]

Gently (and I can't stress that enough) remove the IC's from the sockets, clean the legs, and reseat.

If you aren't gentle, you risk breaking the legs off.

[Ninten-doh]

HaRuMaN, are those custom IC's or ones that you can replace with new programmed chips if they break?

[HaRuMaN]

HaRuMaN, are those custom IC's or ones that you can replace with new programmed chips if they break?

Beats me.    That's why I said be gentle.

[scotthh]

Thanks HaRuMaN, I'll give that a shot tonight. What would you clean the legs with? I have a can of Caig Pro Gold contact cleaner thinking of using.

[scotthh]

Do they make a tool for removing the chips? It's hard to be gentle. I got them out, cleaned and reseated, but needed a drink afterwards... Unfortunately still no sprites.

[HaRuMaN]

Do they make a tool for removing the chips? It's hard to be gentle. I got them out, cleaned and reseated, but needed a drink afterwards... Unfortunately still no sprites.

I bought an IC removal tool just for my PP boards.  On the first chip I tried to extract, the tool broke.     I just use a slim flathead screwdriver, lift one side a little, lift the other side a little, alternating until I get it out.

As far as cleaning the legs, I use a fine sandpaper to knock off the surface corrosion.  I'm sure you could probably use contact cleaner as well.

If the chips trick didn't work, have you checked your voltages and made sure you're getting 5V at the board?  I've heard that 5.1V is even better.

[scotthh]

I messed around with the adjustment on the power supply, I agree, it seems happiest at about 5.1v.

Interestingly the steering stopped working. I messed with the connectors to the board and it started working again before failing again. There is some burn damage to the edge connectors and some soldier repair. Could the edge connector be causing my missing sprites? I could do the edge connector mod sooner rather than later.

[HaRuMaN]

Couldn't hurt.

[fredster]

I have bought new Rom chips from guys on Klov before for SuperPac and Asteroids Deluxe.  It seems to me that pole position games had some kind of metal corrosion issue that eventually broke them down.

I'd dig into it deeper at Klov, but I think the Rom Chip cleaning will help, but there's more to it as I recall.

[scotthh]

I tried to join KLOV a while back and I never got a confirmation email. I successfully joined last week, but I still can't post over there. Almost as frustrating as a PP board 

[Malenko]

I believe that Steph at Hobbyroms.com can make you any roms you may need to replace.

[fredster]

One thing you can try is to test the power supply where the 5 volts actually goes into the board.  Put the probes right on the connector where you can touch the board and see if the voltage is actually 5 volts there.  If it's not, turn it up.  Some of those older games won't die if you bump that voltage up to 5.1 or 5.2 using the pot on the new power supply.  That can sometimes get rid of a graphics issue.

[scotthh]

Tested the power. The power at the switcher power supply is 5.1v, it drops to 4.5v measured at the +5 and ground on the side of the board. I can crank the switcher up to 5.5v to get 5v at the board, but still no large sprites. Actually the whole picture is more washed out at the higher voltage.

There's a sticker with a 1994 date on the board. So it's been worked on at least once. This picture shows some of the newer looking chips on it and what is that blue wire, it's soldered to a few of the chips?


Is this the battery I need to remove? Also, is the trace to the left of there bad?

[fredster]

That trace wire is some kind of repair.  Don't disturb it, somebody put it there for a reason.

When you increase the power to the chips, it's gonna give you a stronger signal to the monitor. It should have been 5 v at the board, so you have fixed the P/S (IMHO).  Just turn down the screen on the monitor flyback.

I'm looking for a manual with schematics. I found this one http://pdf.textfiles.com/manuals/ARCADE/K-R/  Pole position is down there on the list.  Basement arcade has one too. Google for it.

Download the manuals and maybe they can get you to the chip that's actually bad. Older games were pretty well documented so you have a fighting chance of finding the actual bad part.

 But do not disturb that trace wire.  It's not the problem.

[fredster]

I found this today, this part can't hurt...

http://www.ebay.com/itm/Atari-POLE-POSITION-board-PCB-SET-Driving-/200675436923?pt=LH_DefaultDomain_0&hash=item2eb930297b

[Nephasth]

Hold out for one of these: http://forums.arcade-museum.com/showthread.php?t=209988

[fredster]

Now that is cool.

[HaRuMaN]

I want X eleventy

[Spyridon]

Let's see a picture of the cab.  What type of restoration are you going to be doing on it?