Thursday, February 4, 2010


A vandwelling friend had some trouble with his laptop. Laptops tend to fry when you run them with the power on and when the battery is fully charged-- I ruined an old Sony VAIO that way. The charging circuitry doesn't like that, and tends to fry the dc-dc converter inside the unit. The DC-DC converter is usually a set of surface-mount components, not easy to R/R, and usually means replacing the motherboard, which of course on a laptop is pretty close to the same cost as just replacing the laptop.

Now that my van is so quiet, with the new ceiling, and the sunshine is back again, as I'm sitting here in the van working on my netbook, I notice a crackling sound coming from the powersupply section of the netbook. I am running my netbook directly off of my solar, since the netbook wants 12v and my solar electrical system is 12v. But wait. It's not 12v; the solar charger just sends battery voltage out, it doesn't regulate it. So, in sunshine, with my house batteries charged, my netbook is getting anywhere up to 14.1V! Not too smart, and could be frying all kinds of components. May have been doing so for a year, but it's been so damn noisy in here that I haven't noticed the complaints from the switching DC-DC converter inside the unit.

I unplug the laptop from my house batteries. The crackling sound goes away. Drat.

Some quick online shopping locates an external power adapter/regulator (which is, basically, a DC-DC converter itself), to give me regulated 12v, for $15 including shipping. Off goes the credit card, and I'm done. It's possible I've been frying my netbook for the last year. So far, no signs of damage, but I'm not going to risk it any longer. $15 is a lot cheaper than $300.

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