Power supply: Kind of off topic but not really.

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Power supply: Kind of off topic but not really.	Reply
by KD0AFK on June 12, 2008	Mail this to a friend!
I use my laptop for digital but the power supply broke the other day. I don't really want to spend $80+ on a new one if I can at all help it. I do have a Pyramid PS 9KX power supply that I bought at a truck stop when I was a truck driver. Thought it would be good in a pinch for whatever. The laptop power supply is rated at 15V x 5A The Pyramid power supply is rated at 12V x 5A If I rigged a plug that fit my laptop, I could use it right? I think my math is right on this isn't it?

RE: Power supply: Kind of off topic but not really	Reply
by WB2WIK on June 12, 2008	Mail this to a friend!
I'd ask the Tech Support Dept. at the company who manufactured the laptop and ask them this very specific question: "What is the DC input voltage range for this computer?" and then perhaps, "Can this computer be powered directly from an automobile accessory jack?" If the answer to the first question indicates it can be powered by 12V, or the answer to the second one is "yes," you're in good shape. However, that may not be the case. The original power supply was 15V, not 12V, and there could be a valid reason for that. (Offhand, I have no idea...almost everything in a laptop runs off 5V or less, so they are definitely post-regulating that 15V down to much lower voltages inside the computer.) WB2WIK/6

RE: Power supply: Kind of off topic but not really	Reply
by WA7NCL on June 12, 2008	Mail this to a friend!
A lot of laptops run off Li batteries which need a voltage around 15 to 18V to charge them. Even the old NIMH batteries which produced around 12V would need 15 to 18V to charge them using a down converting buck power supply. You probably would need to boost the external supply up to 14 to 15V in order to have it function like the original.

RE: Power supply: Kind of off topic but not really	Reply
by W5FYI on June 12, 2008	Mail this to a friend!
For what it's worth, I've seen laptop power supplies at Goodwill and other resale stores in the $1 to $5 price range, and used laptops with power supplies at yard sales for under $20.

RE: Power supply: Kind of off topic but not really	Reply
by KI4ENS on June 17, 2008	Mail this to a friend!
The Pyramid PS 9KX is most likely a 13.8 vdc supply anyway. So its comparing 13.8 to 15 vdc. I would say its worth a try as long as you monitor it. I am usually not to concerned about going a bit under voltage. Of course how well it charges the batteries is another concern.

RE: Power supply: Kind of off topic but not really	Reply
by KI4ENS on June 17, 2008	Mail this to a friend!
The Pyramid PS 9KX is most likely a 13.8 vdc supply anyway. So its comparing 13.8 to 15 vdc. I would say its worth a try as long as you monitor it. I am usually not to concerned about going a bit under voltage. Of course how well it charges the batteries is another concern.

RE: Power supply: Kind of off topic but not really	Reply
by KE4DRN on June 20, 2008	Mail this to a friend!
hi shawn, try to find a used one on ebay, search for the part # many laptops get turned back in after the lease and the chargers get left behind or if the laptop is stolen the chargers end up on ebay. best to buy the name brand and avoid the knockoff chargers. 73 james

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