Magellan GPS - powering using usb

Author

powering using usb

Noweldrecumbent2

2007-07-04, 10:33 pm

Is it possible to power the sportrak pro with a usb connection? I have a
cigarette lighter power cable that works connected to a solar cell with a
sportrak pro.
Dave

Jack Erbes

2007-07-05, 3:33 pm

Noweldrecumbent2 wrote:
> Is it possible to power the sportrak pro with a usb connection? I have a
> cigarette lighter power cable that works connected to a solar cell with a
> sportrak pro.
> Dave

The external power input for the SporTraks and Meridians is 3.3 to 3.8V
from the OEM cigarette lighter power adapter. So the input voltage from
a USB port, at 5V, would be too much and you would run some risk of
damaging the GPS receiver.

The Meridians and SporTraks all use the same "Power Cable w/ Cig. Ltr.
Adapter", you can see that here:

http://www.magellangps.com/products/accessories.asp

That adapter has a small, rectangular box along the cable. That box
contains a DC-DC inverter that drops the 9-35V input voltage to 3.8V (by
my actual measurements, Magellan does not mention what it is). The DC
3.8V voltage at the connector probably drops a little under load, that
is why I say it needs 3.3 to 3.8V. Somewhere in the Meridian or
SportTrak manuals or spec sheets, those are identified at needed 3.3V
for DC power.

And they will not charge the batteries when they are externally powered.
That is a good thing because they are intended for use with
non-rechargeable alkaline batteries. And bad things can happen when you
try to recharge alkalines.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
(also receiving email at jacker at midmaine.com)

Noweldrecumbent

2007-07-07, 10:33 pm

I noticed that on my sportrak pro cigarette power cable. I was hoping I
could use the proporta mobile survival usb supply to power it like it does
the pda, clearly not going to happen. Do you know if the serial cable is
strickly communications, or power also? Thank you for the information. I
managed to pick up a used meridian from ebay, hope it's as good as the
sportrak I bought awhile back.
Dave

"Jack Erbes" <jackerbes@adelphia.net> wrote in message
news:468d2c37$0$4707
$4c368faf@roadrunner
.com...
> Noweldrecumbent2 wrote:
>
> The external power input for the SporTraks and Meridians is 3.3 to 3.8V
> from the OEM cigarette lighter power adapter. So the input voltage from a
> USB port, at 5V, would be too much and you would run some risk of damaging
> the GPS receiver.
>
> The Meridians and SporTraks all use the same "Power Cable w/ Cig. Ltr.
> Adapter", you can see that here:
>
> http://www.magellangps.com/products/accessories.asp
>
> That adapter has a small, rectangular box along the cable. That box
> contains a DC-DC inverter that drops the 9-35V input voltage to 3.8V (by
> my actual measurements, Magellan does not mention what it is). The DC
> 3.8V voltage at the connector probably drops a little under load, that is
> why I say it needs 3.3 to 3.8V. Somewhere in the Meridian or SportTrak
> manuals or spec sheets, those are identified at needed 3.3V for DC power.
>
> And they will not charge the batteries when they are externally powered.
> That is a good thing because they are intended for use with
> non-rechargeable alkaline batteries. And bad things can happen when you
> try to recharge alkalines.
>
> Jack
>
> --
> Jack Erbes in Ellsworth, Maine, USA - jackerbes at adelphia dot net
> (also receiving email at jacker at midmaine.com)

Jack Erbes

2007-07-07, 10:33 pm

Noweldrecumbent wrote:
> I noticed that on my sportrak pro cigarette power cable. I was hoping I
> could use the proporta mobile survival usb supply to power it like it does
> the pda, clearly not going to happen.

Any DC power source of the right voltage (3.3 to 3.8V) can be used.
Those numbers are not consistent with a USB port (5V) but you could make
or maybe buy a DC-DC inverter that would drop the 5V from a USB port to
3.8V and then you could use it. If your aim is to use one power source
for the GPS and PDA, I'd pursue the voltage dropping inverter.

If you're using the Meridian primarily as the NMEA input for the PDA you
don't need the display on. And in that case, you can get through a
pretty long day (10-12 hours? or more?) on a pair of AA cells.

Jack

Noweldrecumbent2

2007-07-08, 10:33 am

That is my goal. Bicycle touring is alot easier when integrating things to
work together instead of carrying a bunch of different things. I have a
bluetooth SirfII for the pda but mainly use the Magellan, battery life on
the pda is limited, and it does not provide the topo features the dedicated
gps units can. I'll look around for a gps/mobile supplier that can hook me
up with a inverter. Thanks for your help.
Dave

"Jack Erbes" <jacker@midmaine.com> wrote in message
news:469050ab$0$4682
$4c368faf@roadrunner
.com...
> Noweldrecumbent wrote:
>
> Any DC power source of the right voltage (3.3 to 3.8V) can be used. Those
> numbers are not consistent with a USB port (5V) but you could make or
> maybe buy a DC-DC inverter that would drop the 5V from a USB port to 3.8V
> and then you could use it. If your aim is to use one power source for the
> GPS and PDA, I'd pursue the voltage dropping inverter.
>
> If you're using the Meridian primarily as the NMEA input for the PDA you
> don't need the display on. And in that case, you can get through a pretty
> long day (10-12 hours? or more?) on a pair of AA cells.
>
> Jack

Jack Erbes

2007-07-08, 10:33 am

Noweldrecumbent2 wrote:
> That is my goal. Bicycle touring is alot easier when integrating things to
> work together instead of carrying a bunch of different things. I have a
> bluetooth SirfII for the pda but mainly use the Magellan, battery life on
> the pda is limited, and it does not provide the topo features the dedicated
> gps units can. I'll look around for a gps/mobile supplier that can hook me
> up with a inverter. Thanks for your help.
> Dave

If you like to mess with things, try something like this:

http://www.electronickits.com/kit/c.../powe/ck402.htm
http://www.electronickits.com/kit/c.../powe/ck402.pdf

That is just one hit I got with google, maybe someone here knows of a
good source for similar or better kits for do it yourself DC-DC
inverters. I'm not a electronics guy but it is fairly simple to figure
out the input voltage and resistor values needed to tailor the output
voltage on those to your needs.

Those can be packaged real small (1-2" square) and made from readily
available parts (Radio Shack, etc.). Once you have the resistor value
figured out (to control the output voltage) you can often package those
in a small convenient manner and find an easy place to mount them.

I was using an older iPAQ (36xx), with a Magellan MAP330 for a NMEA
input, for a while a few years ago. I was running Ozi Explorer-CE on
the iPAQ and that give me excellent topo mapping as I could use the free
USGS downloads (with some conversion and manipulation).

For that I had two DC-DC inverters, both used 12V in and one provided 5V
to the iPAQ and the other 3.8V to the MAP330. I had the inverters and
MAP330 all in a small padded case, the PDA was Velcro'd to the top and
was used on a ATV.

That setup worked but lacked waterproofing and ruggedness. Over time it
evolved to Magellan and now Garmin handhelds which are hard to beat for
waterproofing, ruggedness, and easy powering.

Jack

Noweldrecumbent

2007-07-10, 3:33 pm

Good idea, I tinker a little bit with electronics, not alot like I used to
back in my phone company days though.
I'll probably upgrade to a Garmin with autorouting next summer. Just didn't
want to have to buy into new software, hardware ect.,,, all at once.
Hopefully the meridian will help me get around till then.
Dave

"Jack Erbes" <jacker@midmaine.com> wrote in message
news:46910182$0$1215
4$4c368faf@roadrunne
r.com...
> Noweldrecumbent2 wrote:
>
> If you like to mess with things, try something like this:
>
> http://www.electronickits.com/kit/c.../powe/ck402.htm
> http://www.electronickits.com/kit/c.../powe/ck402.pdf
>
> That is just one hit I got with google, maybe someone here knows of a good
> source for similar or better kits for do it yourself DC-DC inverters. I'm
> not a electronics guy but it is fairly simple to figure out the input
> voltage and resistor values needed to tailor the output voltage on those
> to your needs.
>
> Those can be packaged real small (1-2" square) and made from readily
> available parts (Radio Shack, etc.). Once you have the resistor value
> figured out (to control the output voltage) you can often package those in
> a small convenient manner and find an easy place to mount them.
>
> I was using an older iPAQ (36xx), with a Magellan MAP330 for a NMEA input,
> for a while a few years ago. I was running Ozi Explorer-CE on the iPAQ
> and that give me excellent topo mapping as I could use the free USGS
> downloads (with some conversion and manipulation).
>
> For that I had two DC-DC inverters, both used 12V in and one provided 5V
> to the iPAQ and the other 3.8V to the MAP330. I had the inverters and
> MAP330 all in a small padded case, the PDA was Velcro'd to the top and was
> used on a ATV.
>
> That setup worked but lacked waterproofing and ruggedness. Over time it
> evolved to Magellan and now Garmin handhelds which are hard to beat for
> waterproofing, ruggedness, and easy powering.
>
> Jack

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