Would it be possible to have the house and engine batteries conected in
series to give 24v, step this down to 18v to power the laptop. Then tap
off each battery for normal 12v service. Sorry if this is a dumb
question but I need a dc supply as the inverter interferes with the ssb
radio when receiving weather faxes.
Tony

Go to Radio Shack and get a 19V cigarette lighter converter.

Or he http://www.powerstream.com/ADC.htm


TB wrote:
Would it be possible to have the house and engine batteries conected in
series to give 24v, step this down to 18v to power the laptop. Then tap
off each battery for normal 12v service. Sorry if this is a dumb
question but I need a dc supply as the inverter interferes with the ssb
radio when receiving weather faxes.
Tony



--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

I owuld either run off of the laptops batteries while recieving FAXs then
recharge them at another time. Or find a small inverter that doesn;t make so
much noise.

Doug

"TB" wrote in message ...
Would it be possible to have the house and engine batteries conected in
series to give 24v, step this down to 18v to power the laptop. Then tap
off each battery for normal 12v service. Sorry if this is a dumb
question but I need a dc supply as the inverter interferes with the ssb
radio when receiving weather faxes.
Tony

That sounds a lot simpler. So this converter is not an inverter then?

Glenn Ashmore wrote:

Go to Radio Shack and get a 19V cigarette lighter converter.

Or he http://www.powerstream.com/ADC.htm


TB wrote:

Would it be possible to have the house and engine batteries conected
in series to give 24v, step this down to 18v to power the laptop. Then
tap off each battery for normal 12v service. Sorry if this is a dumb
question but I need a dc supply as the inverter interferes with the
ssb radio when receiving weather faxes.
Tony

Or this
http://www.mpja.com/productview.asp?product=12974+PS

SP



"TB" wrote in message ...
That sounds a lot simpler. So this converter is not an inverter then?

Glenn Ashmore wrote:

Go to Radio Shack and get a 19V cigarette lighter converter.

Or he http://www.powerstream.com/ADC.htm


TB wrote:

Would it be possible to have the house and engine batteries conected
in series to give 24v, step this down to 18v to power the laptop. Then
tap off each battery for normal 12v service. Sorry if this is a dumb
question but I need a dc supply as the inverter interferes with the
ssb radio when receiving weather faxes.
Tony

Or this one
http://www.idot.com/TheStore/Desktop...stat us=green


"Glenn Ashmore" wrote in message
...
Go to Radio Shack and get a 19V cigarette lighter converter.

Or he http://www.powerstream.com/ADC.htm


TB wrote:
Would it be possible to have the house and engine batteries conected in
series to give 24v, step this down to 18v to power the laptop. Then tap
off each battery for normal 12v service. Sorry if this is a dumb
question but I need a dc supply as the inverter interferes with the ssb
radio when receiving weather faxes.
Tony



--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Watch out if you get the radio shack adapter it puts out +12 volts on
the plus side referenced to ships ground and - 7 volts on the - side
referenced to ships ground for 19 volts. If you want to connect
anything else to your computer that is using ships ground then you
have 7 volts between them and you get an arc maybe blow some stuff up,
for those that want to argue with this just read very carefully the
warning on page 9 (I think, been a while, maybe page 5) of the manual
it is criptic but it is a warning. I had a customer with one of these
and he blew up his 900 dollar ptc-pro sailmail modems!! So I
investigated and found that they move the negative down from the
input reference.

Watch out !

It is good for running your laptop and for charging batteries but you
must disconnect it before you hook anything else up to the computer.
Charge up the battery then disconnect it. Then connect your fax and
radio stuff.

GW




Glenn Ashmore wrote in message ...
Go to Radio Shack and get a 19V cigarette lighter converter.

Or he http://www.powerstream.com/ADC.htm


TB wrote:
Would it be possible to have the house and engine batteries conected in
series to give 24v, step this down to 18v to power the laptop. Then tap
off each battery for normal 12v service. Sorry if this is a dumb
question but I need a dc supply as the inverter interferes with the ssb
radio when receiving weather faxes.
Tony

I do connect the GPS to the lap so It looks as though this may be an
issue. I do run on charged batteries at the moment but the used thinkpad
that i use will run less than 2hrs on a fully charged battery. I tried
our local Radio Shack for the converter this morning with no luck. I
will check their web site for the part#
Tony

Gw wrote:

Watch out if you get the radio shack adapter it puts out +12 volts on
the plus side referenced to ships ground and - 7 volts on the - side
referenced to ships ground for 19 volts. If you want to connect
anything else to your computer that is using ships ground then you
have 7 volts between them and you get an arc maybe blow some stuff up,
for those that want to argue with this just read very carefully the
warning on page 9 (I think, been a while, maybe page 5) of the manual
it is criptic but it is a warning. I had a customer with one of these
and he blew up his 900 dollar ptc-pro sailmail modems!! So I
investigated and found that they move the negative down from the
input reference.

Watch out !

It is good for running your laptop and for charging batteries but you
must disconnect it before you hook anything else up to the computer.
Charge up the battery then disconnect it. Then connect your fax and
radio stuff.

GW




Glenn Ashmore wrote in message ...

Go to Radio Shack and get a 19V cigarette lighter converter.

Or he http://www.powerstream.com/ADC.htm


TB wrote:

Would it be possible to have the house and engine batteries conected in
series to give 24v, step this down to 18v to power the laptop. Then tap
off each battery for normal 12v service. Sorry if this is a dumb
question but I need a dc supply as the inverter interferes with the ssb
radio when receiving weather faxes.
Tony

"TB" wrote in message ...
I do connect the GPS to the lap so It looks as though this may be an
issue. I do run on charged batteries at the moment but the used thinkpad
that i use will run less than 2hrs on a fully charged battery. I tried
our local Radio Shack for the converter this morning with no luck. I
will check their web site for the part#

I think we went through this a month or two ago. Take a look
at www.lindelectronics.com Check out the inverters converters
or what-have-you listed down the right side of the window.

Leanne B
S/V Fundy

I see, so do you think that a 12v DC to 16V DC converter is the answer then?
Tony

Mad Dog wrote:

Yes, using a 6V battery in conjunction with some very extensive
series-parallel
connections and battery isolators you could theoretically design such a
circuit.
But lets consider the source of the interference, alternators are used
insted of generators
on car and boat engines because they are lighter and smaller but alternators
produce alternating current (A/C).
A full wave bridge rectifier consisting of trio diodes is used to convert
A/C into D/C
and a regulator governs output from 13.8 to 14.6VDC.
what a concept huh, anyway the rectifier leaks a small amount of A/C
current into
the regulated D/C.
this small amount of A/C current (700 millivolts) is infamously known as
A/C ripple.
In the D/C world you can call it dirty power because it will infect every
D/C appliance
and electronic gadget that you have turned on.
A/C ripple in a D/C circuit produces NOISE and INTERFERENCE and premature
component failure.
To compund things you are a inverter which inverts the already dirty DC
current back
into a modified square wave which resembles AC current.
****'s gittin deep over here...........
let me know if i'm going to fast 4 ya, what you need to do is condition or
filter the Dc
current before it reaches the intended circuit.
There are 3 types of electrical storage devices: condensers,capacitors and
batteries.
condensers store dc, capacitors store AC and you know what batteries do.
Gittin to the point a capacitor mounted in a DC circuit will block AC while
allowing DC
current to pass, hence we have effectively filtered the DC current.
there are also different types and sizes of capacitors, depending on it's
intended purpose.
keep in mind that DC current flows pos. to neg. thru the battery and
negative to positive thru
a circuit so what this means is grounds are just as important if not more so
than the positive wire.
Several companies make line conditioners for your purpose, but i have always
built my own using large banks of oil-filled electrolytic capacitors wired
in series to handle the demand
for heavy current draw.
Hopefully i have not confused you or gave you a headache as i now have
one..........
but instead given you some insight as to why some DC components dont
function as intended
when operated from rectified AC current.
--
Mad Dog

"TB" wrote in message ...

Would it be possible to have the house and engine batteries conected in
series to give 24v, step this down to 18v to power the laptop. Then tap
off each battery for normal 12v service. Sorry if this is a dumb
question but I need a dc supply as the inverter interferes with the ssb
radio when receiving weather faxes.
Tony