SailNet Community - Reply to Topic

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > On Board > Gear & Maintenance > How to power laptop
 Not a Member? 


Thread: How to power laptop Reply to Thread
Title:
  

By choosing to post the reply below you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Message:
Trackback:
Send Trackbacks to (Separate multiple URLs with spaces) :
Post Icons
You may choose an icon for your message from the following list:
 

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Click here to view the posting rules you are bound to when clicking the
'Submit Reply' button below


Additional Options
Miscellaneous Options

Click here to view the posting rules you are bound to when clicking the
'Submit Reply' button below


Topic Review (Newest First)
09-02-2008 03:42 PM
johnpen2000
Thanks all

I really appreciate all the response. It seems that just using a small inverter (which is what I have been doing) is probably the most practical way for me to go for now. It still irks me though, from an efficiency standpoint. Seems like an opportunity for some electronic engineer/entrepreneur to look at.
09-02-2008 09:56 AM
donradclife A small inverter will do the job more efficiently than a big inverter, but will put out a considerable amount of electrical noise.
09-02-2008 07:35 AM
10011100
Quote:
Originally Posted by johnpen2000 View Post
We have a 120 volt charger for our laptop but I would like to be able to charge up without going through an inverter. It seems very inefficient to jack the 12VDC up to 120VAC with an inverter and then use a transformer to change back to 20VDC or whatever the laptop needs. Does anyone know of a gizmo that converts directly from 12VDC to 20VDC?
Speaking as an electrician, there are a couple of different circuits you could use to step up 12v dc to 20v. Im not sure how happy your insurance company would be about you installing a homebuilt rig on your boat, but if you were happy about the laptop being fairly static it is totally do-able.
09-01-2008 07:49 PM
Gary1 My grumble on this: Why do the new laptops run on such odd DC voltages? I've got an antique IBM Thinkpad that is happy as a lark running directly off the 12 volt system.

My newer Compaq wants to see 18.something volts. Oh, well.

I'd simply run an inverter and be done with it. As to the quality of 'universal' power supplies, I wouldn't touch one with a stick. They aren't regulating the various voltages, they're putting a big dropping resistor in series with the output of the bridge to change the voltage out. Naturally, that means that the current is also going to be down. They certainly aren't worth what you have to pay for them.
09-01-2008 07:23 PM
sailboy21 I am completely unimpressed with the DC power supplies I have seen. They are very expensive, and the universal ones are cheaply made (in spite of their costs!) Cigarette lighter plugs are notoriously unreliable and can be a fire hazard. To make matters worse, in the process of stepping up the DC voltage (very similar to how a inverter works) a very large amount of RF noise is generated. Don't waste your money unless you can verify a specific model works in the marine environment or the store has a good return policy. I find that a quality marine hard-wired inverter with a standard laptop AC adapter is the most reliable. The inverter should have a bonding lug so that it's chassis can be appropriately grounded. It should also be shielded to prevent RF noise. My inverter draws 2-3 amps when powering my laptop. This seems quite reasonable and is certainly no more, maybe even .5amps less than the $90 DC DC adapter that I ended up donating to the dumpster after it almost caught on fire offshore.
09-01-2008 05:29 PM
Kakkerlak
DC/DC converter

I have a Kensington 70 Watt power adapter that I use both aboard and in my minivan to power my Dell D610 and my Dell ATG.

(similar Kensington unit)

The removable Tips are unwieldy, but I think it's more efficient than using an inverter and AC/DC adapter. I must have the tip that only powers, but does not charge, the computer.

I am considering adding a couple of storage batteries in a space near compression post on my Ranger 33 as a second bank to dedicate exclusively to ships computers. When I have my cell phone and PC and anchor someplace with a strong Sprint PCS signal (Fort Townsend State Park has five bars of signal at the mooring buoys !) it's just like I'm at the office. Except I'm smiling every morning.
09-01-2008 02:36 PM
P424 Targus | Mobile Power Store They can help
09-01-2008 02:30 PM
P424 Kensington and Targus have several models of adapters to power your Laptop from a Cigar lighter. The one I have now a Toshiba wont work because no adapter is made..
09-01-2008 02:21 PM
SVDistantStar You might be able to look on ebay and find a charger that plugs into a 12v outlet for your laptop.
09-01-2008 02:18 PM
johnpen2000
How to power laptop

We have a 120 volt charger for our laptop but I would like to be able to charge up without going through an inverter. It seems very inefficient to jack the 12VDC up to 120VAC with an inverter and then use a transformer to change back to 20VDC or whatever the laptop needs. Does anyone know of a gizmo that converts directly from 12VDC to 20VDC?

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


All times are GMT -4. The time now is 08:17 PM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.