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Author Topic: Pole position help needed  (Read 5497 times)
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teetdogs
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« Reply #15 on: February 06, 2015, 09:19:42 pm »

picked up a new 10 ohm differential resistor at a local shop and put it in, game seems to but running like a champ now.  Vertex, I'd like to grab that board from you and recap it just in case.
« Last Edit: February 06, 2015, 09:36:15 pm by teetdogs » Logged
VertexGuy
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« Reply #16 on: February 07, 2015, 02:52:49 am »

picked up a new 10 ohm differential resistor at a local shop and put it in, game seems to but running like a champ now.  Vertex, I'd like to grab that board from you and recap it just in case.

yeah I got the pm,, need the zip for shipping price.
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thegleek
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« Reply #17 on: April 12, 2015, 11:01:12 pm »

Atari's AR power boards are horrible, mainly due to the linear power supply overpowering the poor pcb's causing those resistors to flame!

I've bulletproofed every single one of my Atari AR boards using this advice: http://www.stickycarpet.com/pinx/ar2mods.html

I've even removed that stupid useless R29 resistor and replaced it with a jumper wire, who thought of this +5vdc sense crap? argh!

And sometimes, I just don't wanna with it and go with a switcher cuz it's cheap and dammit it's EZ-2-DO! Smiley
« Last Edit: April 12, 2015, 11:02:54 pm by thegleek » Logged
iankellogg
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« Reply #18 on: April 12, 2015, 11:24:09 pm »

The 5v sense wire is a great idea and if possible should be wired to one of the test points on the board using a separate wire from the main power.  The reason the sense line causes so many problems is because the edge connector gets dirty and oxidizes. This causes the resistance of the connector to go up and the voltage reaching the chips to be too low.  The sense wire sees that and tries to raise the voltage to maintain 5v. As the oxidizing increases the edge connector starts to cook. 
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thegleek
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« Reply #19 on: April 12, 2015, 11:31:04 pm »

yup i hear yea, but everything I ever wanted to know about those AR boards can be found here:

http://bitslicer.tripod.com/ar_sense_mod.htm

http://melchman.net/arcade/Pr0n/tour/ARII/index.html
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