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jfoster
11-28-2009, 10:57 AM
If you have a Linux of Microsoft based suggestion, please open a separate thread about that.

Those with available electrical power enough to keep their ice cream frozen, are not concerned with this topic. Others, with smaller craft may not have even imagined it to be possible to carry an on board Mac computer.

http://www.sust-it.net/energy_saving.php?id=20

A Mac Mini running Rich Ray's MacENC, http://www.macenc.com/
(http://www.macenc.com/)
with 128GB solid-state drive (from Apple or various other sources such as:)
http://www.powerbookmedic.com/128GB-Solid-State-SSD-MacBook--Macbook-Pro-25-Upgrade-p-17244.html#

a USB powered GPS receiver from Mac ENC, BU-353 USB Waterproof 20 Channel GPS

and a small monitor (mostly switched off)

This would be my wish list today. In years past, Greg Nelsen configured a number of rebuilt MacBook laptops with this same functionality. Any comments on using one of Greg's computers or variations on my own Mac wish list?


John

Phil MacFarlane
11-28-2009, 06:02 PM
I have what I think is Greg's original. He called it RoboMac I think. I bought the whole package from him quite a few years ago. Inverted lap top in a home made weather resistant box, AIS receiver, two mice, two water proof key boards and cables and other odds and ends. It had Rich Ray's GPS NavX loaded but I bought another from Rich so as not to screw him and so I would get the updates he sends to all his clients. I love that program.
I didn't pay much for it and I don't think either of us thought it would last very long. After a trip to Hawaii and back and another trip to Mexico and back and scores of local miles it's still going. Some of the best boat bucks I ever spent. Don't recall how much power it draws but it isn't much. While sailing I run it 24-7.
If it ever quits I will do something like you propose John.

Phil

pmummah
12-09-2009, 11:45 AM
Hi John,
I am not sure what your question is. Is it power consumption?
Most notebooks today draw less power than older notebooks. All can be configured for high performance or low power (not both) when running on its battery or when it is plugged in.
If your battery on the notebook is discharged the power draw to charge it can be quite high, especially if you have a notebook that rapidly recharges. If you are also running a program it can be even higher.

Typically, idle with the screen blank is 6-8 watts. Add a watt or two for the screen on at minimum brightness. Screen brightness is important for power also, so run with as dim a screen as possible. Full brighness can add another 1 1/2 watts. This varies with the age of the computer. Older computers have less efficient screens.
If you are running a program that requires a lot of CPU or graphics work the power can jump up to 25 - 35 watts.

A Mac Air (thin) book draws less power than most notebooks.
Netbooks also draw less power. Intel's Atom processor is slower but consumes less power.

Thngs to do to keep the draw from your boat power low:
Blank the screen
Do not charge the notebook when running a program that requires CPU or GPU to run at a higher rate
Don't plug unncessary devices into the USB ports. Each device draws power. External key boards draw power too.
Configure the device power management for max power savings. This can be done in AC mode also, which is what the computer is running in if you plug it into anything, even your battery bank. It will be a bit slower but draw less.