Re: Centipede

My guess is something's up with the AR II board....or the edge connector. I
know you said you rebuilt the AR II board. If you've got juice at the
10.3VDC lug of the AR II board, your bridge rectifier on the power block is
more than likely good.

<On the board:>
<The +/- 22v show as 15v>
This voltage is wrong. I don't really see how this could be, but it's not
right. It should be noted, this voltage isn't important for the game to boot
up and play. This is only used for the high score save. 36VAC enters the AR
II board from the power block...The juice then goes through diodes
CR5/CR6/CR7/CR8 and caps C18/C19 on the AR II board. The juice now
becomes -22 & +22 VDC. It leaves the AR II board and enters the mother
board.

<28v shows as 25v >
These should be -28 & -25. These are also only for the high score save.

<+10.3v shows as +15.3v.>
This is probably OK. This is an unregulated line.

AR II board
<Both 36VAC show as 18.3VAC>
This is fine.

<+12v shows as +11.8,>
This is fine

<-5v shows as -15v>
This is way off. -5VDC comes from the -22VDC line. After C19, -22VDC goes
through C31/Q9/C24 to become -5VDC.

<+22V shows as +24.8v>
This is fine. This line is unregulated

<-22V shows as -25.2v>
This is fine. This line is unregulated.

Check the edge connector for any burnt or bent pins. Check the work on the
AR II board...anything put in backwards or solder bridges. Re-check those
voltage test points. Some of those don't seem possible...is the battery
getting low in your meter?

Big blue could be going bad. If it looks original, it wouldn't hurt to
replace it. As for testing a bridge...think of it as four diodes tied
together (that's what it is). Put your meter on diode test. Pick any two
legs...black to one...red to the other. You should get a reading of nothing
or .4-.7 (give or take). Just like a diode.Reverse the leads on the same two
legs. If you got nothing the first time....this should be the .4-.7 reading.
If you got .4-.7 reading the first time...this reading should be nothing.
Keep going around the square bridge until you've tested all the legs. No
funky readings or shorts, bridge is probably good.

Edward








"Scott Caldwell" <lscottcaldwell@xxxxxxxxxx> wrote in message
news:wFSZi.20290$lD6.13785@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Well, after a perfect record to date (in my possession) my Centipede
cabaret died yesterday. I've done the following, but the game still
isn't working, so I am open to some suggestions. I've been googling
this and found varying ideas or solutions.

Game is getting AC (+119.6VAC at the marquee light leads on the
brick), since the marquee lights and the coin door lights are on.
The +5v LED on the boardset is not lighting, I get no response in
test mode, no start button lights, etc. The monitor is working,
since I can see the full, white screen when the brightness is turned
up.

Note: All voltage measurements were taken with everything plugged in,
so there should be a load on the ARII.

On the board:
-------------
Measured voltages and +5v starts at 4.6/4.7, then drops to 0.4 within
a minute or less. The +/- 22v show as 15v, 15v show as 15v, 28v
shows as 25v and +10.3v shows as +15.3v.

On the ARII:
------------
Both 36VAC show as 18.3VAC, +12v shows as +11.8, -5v shows as -15v,
+22V shows as +24.8v, -22V shows as -25.2v.

What I tested/did so far:
-------------------------
- Tried boardset on my JAMMA tech bench and it works fine (+5v LED
works).
- Rebuilt ARII-02 using Bob Robert's hit, removed and replaced all
solder on plug connectors (5), replaced Q2, Q3, Q8 & Q9
- Tried another ARII-02 (untested, so this is no conclusive)
- Plugged/unplugged connectors into the ARII several times, then did
the brick plugs.
- Tested all fuses (fine).


I have not replaced the Big Blue in the game, but that can easily be
done. I don't know how to test the bridge rectifier in the brick (trying
to google that now, but speak-up if you know), but would that
explain what I am seeing above?

Any help is appreciated.

Scott C.


.

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