130XE Electrical Problem

[hueyjones70]

I have a dead 130XE, There is correct voltage at the DIN connector and on the bottom pin of the switch when the switch is OFF. When I turn the switch ON, I get no voltage on any of the switch pins or anywhere else on the board. I have replaced the switch and tried multiple power supplies. What could be some possible problems, I have a workinf 130XE that I am using for comparison purposes.

[Osgeld]

something shorted, measure resistance tween ground and the switch

[+Nezgar]

Based on my very recent experience repairing a power supply that was dipping voltage under load in this thread: http://atariage.com/forums/topic/270369-failing-psus-what-do-they-put-out/- my first guess is a failed 5V voltage regulator.

 

However, the type of power supply you have will determine the level of difficulty getting into and servicing it... It may be easier to hack off the cord with the DIN connector and connect it to a modern 5V USB charger (of at least 1.5A)

 

Can you post a pic of the power supply brick?

[hueyjones70]

I have used 3 different power supplies that work perfectly with the other XE.

[+bob1200xl]

If the +5v circuits are shorted somewhere, the regulators will shut down, giving you 0v on your computer (rather than smoke and melted wiring). This is a designed safety feature of the regulators.

 

You need to remove as much as you can from the +5v and see if you can find the short. Capacitors are most likely.

 

Did this 130XE ever work for you?

 

Bob

[_The Doctor__]

that'd be the way... caps(any bulging and or leak marks on the pcb) then diodes then chips..... almost anything else would look cooked... do very good visual inspection of the components on the pcb... decent light and a magnifying lense are helpful

Edited November 2, 2017 by _The Doctor__

[hueyjones70]

Yes it has worked, as a matter of fact while I was checking resistance on the switch it came on, so Now I have to worry about it burning something out if I turn it on to check something.

[_The Doctor__]

If it came on while prodding and nothing is smoking leave it on for at least a day to allow caps to reform... then when you turn it off look for cold solder joints and trace breaks.. then after all that, touch up suspect cold cracked or dull joints.. power it up again... if it come on again.. test the crap out of it!

Edited November 3, 2017 by _The Doctor__

[hueyjones70]

Sam's manual says to check C2 for 5v, I know where C2 is and I can check it but I can't find any reference to what the nomenclature is for the capacitor in case I need to replace it. Does the 130XE generally have the same part designators as the 800XL; I have a parts list for the 800XL.

[BillC]

Sam's manual says to check C2 for 5v, I know where C2 is and I can check it but I can't find any reference to what the nomenclature is for the capacitor in case I need to replace it. Does the 130XE generally have the same part designators as the 800XL; I have a parts list for the 800XL.

C2 is a 22uF 16V axial electrolytic capacitor, the 130XE Reference Manual from Atari has a parts list at the front of the book.