Millipese power

Seifer13

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So Ive been trying to get my Millipede working for months now and I can't figure out whats wrong with it. At first the graphics were all messed up and wouldn't boot. I was told it was a voltage problem. Switched out the power supply and now I get nothing. The little LED doesn't even turn on. So I though it might be the AR board so I got a rebuilt one and it does the same thing. Monitor and marquee light turns on so Im assuming the power is ok. Any tips on how to test the voltage on an atari board and power supply?
 
Throwing parts in the general direction of the cabinet isn't a very easy way to get it working :) Troubleshoot first. Then replace parts.

You need to check the voltages at the game PCB, and ensure that everything is correct. There is obviously power getting to the game, since the marquee light comes on, but that runs on 120VAC, completely independent of the DC power supply that runs the board. It doesn't tell you much.

Also, when you say "power supply" that you switched out first, what exactly did you change? Millipede uses a standard AR-II based linear power supply. There is a transformer brick at the bottom of the game that produces the unregulated 10.3VDC that the AR-II uses as input (as well as containing an isolation transformer for the monitor), then the AR-II board itself regulates to produce the DC voltages needed by the game board.

Check the voltage at the AR-II board, there should be a 10.3V test point - see if you are getting input power to the AR-II. Then you can test the power at the game board to verify you are getting a good 5V.

-Ian
 
Ok thanks! Yeah Im still pretty new to this so I just try replacing stuff with working parts. I got nothing from the AR2. Where should I check from there?
 
I got nothing from the AR2.

By this, do you mean, you're not getting anything at the 10.3V test point on the ARII?

If that's the case, then you have something wrong in the power brick. There are three parts in that circuit. The fuse, bridge rectifier block, and the large blue capacitor. If you're getting nothing at all, then chances are your fuse is blown. If it's blown, and it blows again, then the bridge rectifier is probably shot.

Or, if you are getting a reading at the 10.3V test point, but not on any of the outputs, you need to start tracing things on the AR-II board itself.

-Ian
 
All the fuses seem to be fine though.

Seem to be fine, or are fine? A fuse can look good but still be blown. Another common failure on the power brick is a burned connection on the fuse for the unregulated DC. There's a fair bit of current draw there, and the wire will burn and break at the spade terminal.

I sent you a PM, give me a call tonight and I'll try to help you over the phone, I think it would be easier to explain some of this stuff that way.

-Ian
 
Thanks sooooo much that would be amazing. Ive been trying to get this to work for months. And just for reference I found a bad fuse replaced it but when I turned it back on it got super red then died back out but it still passed the continuity test. Ill give you a call later. Thanks again!
 
And just for reference I found a bad fuse replaced it but when I turned it back on it got super red then died back out
It's not supposed to do that. There is no such thing as an "illuminating fuse". :D You have a short. Probably a bad bridge rectifier.

but it still passed the continuity test.
It passed... while it was still installed in the fuse holder, right? Pull it out and check it again.

Ill give you a call later. Thanks again!
Talk to you then! You're welcome!

-Ian
 
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