[jagasail]

Manou,
This is a followup to your comments on your MacENC/GPSNavX presentation about the Mini:

http://www.macsailing.net/fbb/showtopic.php?tid/695/

On the power consumption - I read through the article you referenced and it appeared this was just for the mini and did not include a monitor. What your post said (and the article) works out to about 1 ah at idle and 2+ ah running. What do you think your consumption would be with a small monitor? My biggest disappointment in using a computer onboard has been the power consumption. My Macbook seems to draw upwards of 4 ah much of the time, making the potentially the biggest power draw on my boat (more than my refer). That alone has pushed me away from using it for ongoing navigation, and instead more for planning. I'm trying to keep my total 'cruising' power usage at or under 100 ah/day.

Scot

[donalphilby]

Scot,
Where is the draw from on a laptop? I know it is large--just feel the power cord box. Do you have airport turned off? That would be a large draw. My cell phone out of range even gets hot. Is it possible to create a RAM disk and download charting SW and needed charts into it so little HD access? Is it the screen? If so, smaller iBook...and quick to activate sleep mode (though I wonder what that does to the ongoing track record).

donal

[cyberhusky]

I do have a 10" TFT touchscreen (1024x768 pixels) which works with 12V. (look for them at ebay).
I don't know how much A the draw. Normally I do use my MacBook as chart plotter and the TFT touchscreen as external monitor.

[cyberhusky]

Here's an interesting site concerning power consumption and PC on board!
Unfortunately it's in French, but Google Translator should convert it to your appropriate langage,

http://www.voilelec.com/pages/pcporta.php

Regards,

Manou

[Eric Frank]

I do have a 10" TFT touchscreen (1024x768 pixels) which works with 12V. (look for them at ebay).
I don't know how much A the draw. Normally I do use my MacBook as chart plotter and the TFT touchscreen as external monitor.

To cut down power consumption for MacENC or GPSNavX on my Powerbook, I use a script that updates the position every 2, 5, or 10 minutes and sleeps the Mac in between taking these readings. This cuts the power consumption a lot, even taking points every 2 minutes. Works most efficiently with the older Powerbooks (not Intel) which have lower power consumption and sleep faster when you put them to sleep. Average power consumption is probably about 1 Amp. I do find that it does not work reliably with Bluetooth, as Bluetooth does not always reconnect when the Mac wakes up. But with the serial-to-USB converter, it works fine.
I am happy to share this script with anyone who would like it. Have used it for a couple of years now.

Eric