Well, I ended up taking two Centipede cocktails off of another local collector as a package deal.  Still want that Gorf, though…  Will have to come back t that one soon!

But I digress…  So I have two Centipede cocktails here.  One of them has a dead monitor (and a non-working board, I later discovered), and the other will not sync:

Centipede #1 - No Sync

(Note how dirty the control panel is, as well as the color of the button and trackball to compare with another picture later in this post.)  Checked the wiring, the connectors, adjustments/controls and nothing would get it right, so I went to capping it.  Here is a picture of it half way done on my bench:

downsized_1203091924

After capping it (and also doing the sync improvement upgrade while I was there), all it took was a few adjustments and the screen came up sharp and clear.  This image also shows one of the rebuilt trackballs, which is now running as smooth as when it came out of the crate:

1203092025_rot

 The text looks a bit blurry, but only in the picture.  The screen is really sharp!  You can also see a new shiny trackball at the bottom too.  Next to it is a really dirty button.  Here is one of the panels (from the other cocktail, because its panels are in better condition) with a replacement button and a (unmounted) rebuilt trackball after being cleaned up a bit:

1203092142

All in all, not bad for about 3 or so hours of work, if I do say so myself.  (3 hours for everything, not just cleaning this panel! :)

Now, that other cocktail… that one is gonna be a bit harder…

Problem: Stiff spinning steering modules and hard shifting between gears

(Quick little story – while bringing this beast into its location, I fell and got pinned under it for a few minutes. It is amazing how much having your chest compressed effects your ability to call out for help! :)

OK – onto the next issue… Its steering wheels were pretty stiff, and if you tried to give them a good hard spin they would come to a halt within a couple of turns. Removing and disassembling them was easy. Turns out the problem was that the old grease in them had coagulated/thickened so that it was about as viscous and sticky as cold honey!

Getting the grease out of the barrel and off of the shaft and sleeves literally took ~10 minutes (for each module) with some rubbing alcohol, elbow grease and rags. I had a friend helping me (Sean) and we each tackled one sterring wheel each.

After getting that old gunk out, a quick application of some light lithium grease on everything solves that problem – the wheels will now spin for at least 10 turns easily.

For the shifter modules, I just applied some powered graphite to the shifter “ball” at the opening of the shifter and after a few shifts to get it all around, the shifts are much easier now.

Solution: Cleaned and lubricated the steering modules, lubricated the shifter modules.

Note: One of the steering modules has a broken shaft/cone, which caused the wheel to be off-center, and it was being held in place strictly by the force of the retaining bolt that goes through the entire assembly. I managed to get it a bit straighter than it was before, but it still is broken internally. Not sure if I want to go through sanding down the two halves to try to get them melded or epoxied together – I am afraid of shortening the cone too much and causing problems. The wheel works and the game is playable, so I might just leave it as it is.

Problem: Static garbage on screen

Purchased a Sprint 2 in non-working condition. Saw a picture of it, monitor worked – it showing what appeared to be static garbage on it. Got it home and confirmed that yes, it is showing static garbage (first image below). Turning it off for a couple of seconds and then back on again keeps pretty much the same garbage display, but sometimes gets some sounds out of it (engine and/or screeching sounds). Moving the self-test switch does nothing. First suspect that CPU is not running, because the screen is static (i.e. not changing while the game is on).

Sprint 2 - Before

After checking the usual suspects (voltages, loose wires, harness/wire burns because this is an older Atari game…), I yank the CPU to see if I get the same results (to narrow it down to the CPU). This causes a different effect, a screen filled with a single character and I get sound, so I presume for now that the CPU is working and the problem lies elsewhere.

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I bought two or three sets of unknown/untested/bad boards sometime last year. I have recently started going through them to determine the severity of their problem(s). (This is taking a surprisingly long amount of time due to the time it takes to create a JAMMA adapters for each unique interface! :/ )

Anyhoo, I came across a complete, intact Kangaroo board last weekend! After creating a minimal adapter (Power and Video), the board came right up! I tried its self-test and it passed. After watching the attract mode for a little bit (~30 seconds), the game started to show some visual artifacts on the RHS of the screen. They were horizontal blurbs that looked like multicolor static. However, each of the blurbs, while in a random vertical location, were identical.

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Purchased described as “Has a ROM error“. Started by creating a JAMMA adapter, and then read the EPROM at 2E, it was not found under Romident, burned and installed a replacement. No change. Removed and read all ROMs in row/column 2, and all but one of them failed to be identified by Romident, burned and installed 5 more replacements, working! Still have to wire up an amplifier to correctly test the sound, but looks good so far.

[07/30/03] I finally found the brain cell that got me to realize that I could use my inductive listener (a telecom tool, often used with a tone tracer) to test the sound. It works!

Solution: Replaced bad ROMs

(Recently, the board is starting to develop an intermittent problem with a bad socket. I am going to replace it as the first use of my soon-to-be-here combination soldering/desoldering station.)

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