My free non-working Pole Position (and heat question)

[TheOtherBob]

I picked up a decent (not great) non-working Pole Position that was free via the local paper.  One 25 amp fuse later and all seems well again (gotta love that!).

So I decided to donate it to an upcoming silent auction for charity.  I'm cleaning it up a bit and making sure it will hold up for whomever wins it.  I noticed on an ebay auction for a PP it had some fan duct mounted over the pcb cage.  My PP doesn't have this ductwork.  Also the fan mounts to the back cover instead of inside the PP like the one on ebay.  The manual I have for PP doesn't mention this fancy ductwork at all.  Does PP really need some kind of duct over the cage for the fan?

It looks like it has been repaired before as the grounds and +5 go direct to the board and not via the edge connector.

Sorry for the crappy cell phone pics that always seem a bit out of focus on my phone....

Thanks for the help!

[D_Zoot]

PP's generate tons of heat (those boards are power hogs) thus the reason for the duct and fan.   It's not uncommon for that duct to be missing for some reason.  The last Pole I did was also missing that duct but still had the fan in place.  I wound up making a duct out of some light cardboard (which is all the original duct was).  I would suggest you do something similar.

Pole's also had a big tendency to burn up the edge connector due to the high current load on the +5v and ground circuits.  That's probably why the edge connector is bypassed.  Usually the +5v and ground circuits were jumped directly to the +5v and GND test lugs on the boards.  If it looks like a good solid job then I would leave it like that.

Originally PP's were underfused from the factory.  There was a bulletin from Atari to up the fuse.  I think the original was 15a and it was suggested to up it to 20a, but I could be wrong about the fuse sizes, that was from memory.  I have seen problems on the power brick where bad connections at the fuse clips caused the clip to overheat and blew the fuse just from excessive heating of the fuse.  You might want to check that.

A couple of  other things I would suggest to help improve reliability.  First, go over the power brick fully and check for signs of connector heating or thermal stress at the fuse clips and rectifier bridge, very common.  Next perform the sense mods to the ARII boards (google for instructions), this helps prevent a board edge connector problem from causing the ARII to drive up the +5v line and roaching the board.  Lastly add a fan to the bottom of the cab to circulate air across the brick and ARII boards.   

You are lucky you got one with a working board set!  It's very common to have board problems and they are a real pain to fix.

Regards,
D

[Ken Layton]

The manuals were printed right at the very start of Pole Position's production run. There's a story behind the fans (or lack of) in the cabinets/backdoors.

Most of the Pole Positions I have worked on did NOT have any fans. Later in the production run, Atari got tons of heat related complaints and decided to make changes on the production line. Some cabinets had a fan hole cut into the backdoor and a fan on L brackets was put over the boardset blowing on the board cage. Some cabinets had a fanhole cut into the back door and a fan was mounted to that hole and a cardboard "tunnel" put over the fan to guide the air into the board cage. Some cabinets merely had a hole cut into the back door and no fans at all. None of this was documented.

[TheOtherBob]

I would suggest you do something similar.

Will do..... I made a new bezel for it with some picture framing material so I'm already ready with my l33t cardboard skills.....

A couple of  other things I would suggest to help improve reliability.  First, go over the power brick fully and check for signs of connector heating or thermal stress at the fuse clips and rectifier bridge, very common.  Next perform the sense mods to the ARII boards (google for instructions), this helps prevent a board edge connector problem from causing the ARII to drive up the +5v line and roaching the board.  Lastly add a fan to the bottom of the cab to circulate air across the brick and ARII boards.   

You are lucky you got one with a working board set!  It's very common to have board problems and they are a real pain to fix.

Will do......

I checked and Atari did recommend upping the fuse from 20 to 25.  I figured I got lucky with the fuse thingy.....

Thanks all!

ps. If anybody is near Prior Lake, MN and are interested in a PP, PM me and I'll let you know where it'll be this weekend for the silent auction.