Power supply issues

[Sawyer10702]

Hey gentleman,
My power Supply has taken a blow my pink wire 5vdc for cpu only reads 4.2 vdc not enough to wake up the c pu so I used a switching power supply 5vdc and it works. My question anyone have a update for rectifiers ?? And the transistor out side on top of power supply? Thanks I'm advance for any help

[KaPH33n]

TOPIC SPLIT. For future, please don't add to different threads/different subjects. Simply start a new thread.
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I would say we should try to diagnose what's wrong with your power supply as that will be a better fix in the long term in my opinion. As opposed to having two power supplies dependency. Can you take pictures of the components you are talking about? Not sure which rectifiers you are talking about.

[Sawyer10702]

I should have mentioned the bridge rectifiers! I have all the parts already I'm going to replace caps: 22000if 50v, 6800if 50v, 10000if 50v those are all the big caps. 1000if 50v small cap these are all 105degrees caps not 85 which was original. I'm going to replace the 5vdc 4amp voltage regulator along with the two 0.33uf tetalon caps for voltage regulator. I'll probably use some heat sink paste for bridge rectifiers. I checked trans former input and out puts they check out. I've removed the filter years ago when I first for machine that was no good why it wasn't working. I will give update on how it goes. One thing to mention it the grounds on the voltage regulator went making good connections this won't be good for voltage regulator when lowering up. Thanks please ask any questions we can all learn from this and get our machines back up and running sometimes people feel discouraged going into the power supply for the newbies but becareful some of those big caps put out a punch you can short them with a screwdriver or crocodile clip from positive to ground on chasis. B E careful when going inside and don't forget to unplug it.

[KaPH33n]

I am not positive but I assume your bridge is rectified since you have DC output at 4.2 volts. I would agree with you the caps probably need replacing, but I suspect the 5v voltage regulator more. 105 degree caps are better than 85 degree ones and won't give you a problem.

[Sawyer10702]

I will post how it works out! Thanks for reply I should have it up working soon. I forgot to mention probably a good sign that the voltage regulator is degrading the p/s is to hot to touch.with hand like seriously burn it!

[Sawyer10702]

So I have installed all new caps, including the small 0.33 uf on the voltage regulater. Note these also have a positive/negative legs. I've also replaced the voltage regulator. The blue wire that on one of the legs of the voltage regulator goes to one of the bridge rectifiers which supply 5vdc to the cpu is also bad the diodes inside are giving a ohms reading for both ways. So I'm waiting on a 8amp, 400v bridge rectifier to come in post has soon has that is replaced it should be working will test before I install it on machine! I purchased some of my caps from arcadeparts&Repair he had the 1000if snap on cap for cheaper and also be had 1000if and 6200uf all 50v so if your looking to rebuild your power supply. If your unit is getting hot check that rectifier with blue wire from voltage regulator. I guess there's not much action on the universal slot these days ??