Mailport November 2013 Issue

Mailport: November 2013

12-volt Macs

Photo courtesy of Giff Jones

Reader Giff Jones's modified Nauticat 38 was named after the famous mermaid statue in Helsiniki Square, Havis Amanda.

Great article on navigation software for Macintosh computers (PS, July 2013). I have been having so much difficulty getting a GPS signal into my GPSNavX (via Keyspan HS19) that I rejoiced to read about OpenCPN.

But when I tried to download it, I ran into a few problems: 1. There’s nothing to tell you which version to download for non-Intel Macs (OS 10.4.11); 2. After spending two hours on this project, I ended being unable to contact anyone (even via email) at the company to ask for advice. I finally found a remote item under FAQs that confirmed all: Using OS 10.4.11 on my old-dinosaur Mac PowerBook G4 doesn’t cut it with OpenCPN.

It may be time for an upgrade. I have stuck with my old G4 because I can run it directly on my 12-volt system. Can you recommend a newer Mac laptop that will still run on 12-volt power? And are 12-volt power supplies available? I am loathe—for old-fashioned reasons—to dedicate a separate inverter just for the laptop.

Giff Jones
Havis Amanda, 1984 Nauticat 38
Lake Union, Seattle

We suggest checking with a Mac/Apple vendor, but there seem to be many options for an auto-adapter that can match the output voltage required for Macbook Pro or other Mac laptops. Typically designed for charging a device via a car’s cigarette-lighter socket, the adapters use 12-volt power and outputs range from 45 watts to 85 watts. This is a pretty straightforward process, so we imagine you’ll have a few options. We’ve not yet tested these adapters, but www.macbookadapter.com seems to have a varied selection.

Another option would be to use a pocket inverter like those made by Duracell. This may be a safer method, but it’ll also be slightly less efficient.

Next: Keeping It Cool

Comments (1)

Based on the Mailport recommendation of the Batteries Plus store service, I called the closest store (Orange, CT) about rebuilding the N-mH batteries for my Panasonic cordless drills of which I have many. With exact info on the batteries given over the phone, I was quote $36 per battery with a possible discount for quantity. Upon arriving I was then quoted $90, more than new replacements. When I protested the price, I was then quoted between $10 and $20 which seemed more than reasonable. When I proffered a single battery for rebuild, the new estimate came to $60. By that time I had lost confidence and left, though not before noting that they have a wide selection of batteries for sale all of which seemed over-priced.

Posted by: MICHAEL B | November 15, 2013 8:42 AM    Report this comment

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