Build Your Own Arcade Controls Forum

Arcade Collecting => Miscellaneous Arcade Talk => Topic started by: shilmover on December 18, 2007, 11:30:29 am

Title: Millipede power supply problems
Post by: shilmover on December 18, 2007, 11:30:29 am

Got a Millipede yesterday and it has some issues.  When I power it up, the screen displays random characters.

According to the seller, its a power supply problem not sending enough power to the PCB and that I should change out the Cap and Voltage Reg.

Can anyone comment on whether that could cause it? or is it a bad board?

Title: Re: Millipede power supply problems
Post by: D_Zoot on December 18, 2007, 12:16:53 pm

Could be power supply, could be bad connections, could be a board problem. 

Probably should measure the voltages at the game board edge connector before making any assumptions.


D

Title: Re: Millipede power supply problems
Post by: Level42 on December 18, 2007, 12:37:12 pm

Is that screen completely static ? If so, it reminds me a lot of my first Centipede issue.
(http://forum.arcadecontrols.com/index.php?topic=63654.msg753810#msg753810)

My suggestion is to first check the voltages on the PCB. There are lots of testpoints where you can measure them. If these are OK, try to short one of the +5V test points to the reset pin of the 6502 (pin 40) and see if it runs then.

Title: Re: Millipede power supply problems
Post by: shilmover on December 18, 2007, 05:14:27 pm

Yup.  Its static.  Nothing changes.  Just checked your post and its identical to mine!!!  how did you get a picture of my cab?!?   :angry:  >:D

I will check the voltages tonight.

Title: Re: Millipede power supply problems
Post by: shilmover on December 18, 2007, 10:12:36 pm

Rebuilt AR board.

GND to +5v = 5.18-5.21V

GND to pin 40 of 6502 = 4.78-5.08V

Title: Re: Millipede power supply problems
Post by: Level42 on December 19, 2007, 01:26:32 am

OK, so the power is OK, reset line is OK too....

Does anything happen when you push (and hold) the reset button ?

Title: Re: Millipede power supply problems
Post by: shilmover on December 19, 2007, 12:43:24 pm

Quote from: Level42 on December 19, 2007, 01:26:32 am

OK, so the power is OK, reset line is OK too....

Does anything happen when you push (and hold) the reset button ?

I do not see a reset button on the board.  Where is it on the centi?

Title: Re: Millipede power supply problems
Post by: Level42 on December 19, 2007, 02:56:35 pm

On the wrong side....no really, I'm serious, it's all the way at the end you have to reach in completely. It doesn't look like a button, more like a disk-like object. It feels like it doesn't do anything, but it sure does. At least, this is all true for the Centipede.

Title: Re: Millipede power supply problems
Post by: shilmover on December 19, 2007, 03:53:02 pm

Didn't see one, but will look again.