WTB DC to DC converter to use Dell Laptop in a 12 vehicle + a second item

[Karl W4KRL]

I bought one at a hamfest a few years ago for my HP Pavilion. Can't say I
ever did any serious RFI testing but never noticed any problem. The
nameplate says NotebookParts.com but Googling the model number turns up a
lot of suppliers such as allforlaptops.com and laptoppartsshop.com. My
specific part number is SYD1109-6019. It appears to be made with the same
(good) quality as an OEM 120Vac supply. Input is 10-15Vdc @ 6.5A. Output is
19Vdc @3.16A (exactly like the OEM 120Vac supply.) I think I paid about $25
at the show. Haven't seen any since.

By the way, this is much more efficient than plugging your 120Vac charger
into an inverter. This way there are three stages of power conversion versus
six:

[DC-DC Supply]         [inverter]     [OEM charger]
[inv./xfmr./rect.] <=> [inv./xfmr.] + [rect./inv./xfmr./rect.]

The dc-dc converter may have an efficiency of say 92% while the inverter and
OEM charger may each be about 90% for an overall efficiency of 81%.

73 Karl W4KRL

-----Original Message-----
From: Robert E. Seastrom [mailto:rs at seastrom.com] 
Sent: Tuesday, August 05, 2008 10:21 AM
To: Alex Fraser
Cc: tacos AMRAD
Subject: Re: WTB DC to DC converter to use Dell Laptop in a 12 vehicle + a
second item


You have to pay careful attention to those guys, since they often are
engineered to use 15v airline power (on a cigarette lighter socket or
Empower, the funky airline connector) and do not measure up to
expectations on 12v.  The cheap ones are RF-noisy.

The gold standard ones are made by http://www.lindelectronics.com/

I have powerpoles on mine too.  :)

-r

> writes:

> They make a gizmo to convert auto or airline power for laptops.  They go
for
> about $20~30 on ebay.  I have used one (a different brand) and it works
great.
> [[ebay]]
>  I of course switched out the cigarette lighter plug to a powerpole.  To
make
> it so I could plug into any car I have a cigarette lighter plug to power
pole
> adapter that I run into a powerpole distribution strip.  This gives me
enough
> power for laptop, gps puck and cell phone for internet access.  If you
have to
> run a radio of any wattage of course you must go direct to battery, but
how
> often do people let you set up you radio in their car?
> Michael Chisena wrote:
>
>

>  Hi all,     As you know I have this RDF bug, and one of the things that
needs       
>  solving is how to run the lap top in the truck.     Have a Jotto desk
(like what    
>  the cops use for their mobile data terminals) but the battery in an
elderly Dell    
>  Lap top won't last long if at all.     Just wondering if any of you had a
proper    
>  vehicle dc to dc converter. New or used, all it has to do is run. The
Dell needs 20 
>  volts of output at the best guess of 3 amps or less. The OEM neglected to
put a     
>  current rating on the factory power supply. The three amps number is a
good         
>  guess.     I have a DC to 120 vac inverter that I don't want to use. The
last time  
>  I used it, the spikes and surges trashed my alternator, and I'm not
willing to try  
>  that experiment again.     So if one is for sale, I'm game.     Second
item     At  
>  the fest yesterday I got three tentative orders for standard APRS
mobiles.     Of   
>  this style

>  conversion...
[[http://www.flickr.com/photos/90108848@N00/sets/72157604093886156/]] 
>      The only difference is the radio. The 2m unit from the photos is a 35
watt.     
>  I have some radios that will deliver 80 watts. Got in a lot of ten units.
Two have  
>  been converted to base stations, one of those is on the air with W1CAR in
West      
>  Virginia.     The transmit power is easy to adjust down if desired. From
about 20   
>  to 80 with a single 'pot' adjuster.     The thinking is, if I'm going to
do three,  
>  i can do the remaining seven or eight units from the set.      If you
want one, get 
>  back to me off list and we can work out the details.       Thanks in
advance Mike