GPS on PDA, the energy bottom line

Shoeminator · 10-04-04, 12:10 AM

Hi All,

A quick question (hopefully new). I', looking at a GPS for an axim (x50 if the darned thing ever gets released) or other pocket PC.
The way I see it a CF based GPS sucks about 90mA from the PDA's battery. This would lead to suggesting operational longevity would be better served using a bluetooth GPS and keeping the PDA's battery for running the PDA .... BUT .... how much power does a bluetooth transmitter suck when operating ?

if anyone has any figures on this it'd be great

Thanks

Shoei

axim2go · 10-04-04, 08:17 AM

That is an interesting question and I like to know also. However, I will be buying the CF GPS called SysOn CF Memory GPS w/ Xtrac 2.0 with 512 MB memory because I can use it while walking, jogging, biking, hiking, etc...
It is more mobile. I don't think would drain that much energy and it is more convient than having to carry 2 units (PPC and GPS) and having to worry about recharging 2 units.

The way that I see it is: if you are worry about battery life, just get a spare battery for your pocket PC. I see this as a better option than having to worry about carrying 2 units. The only drawback about a CF GPS is that it adds a little bit of total weight once the CF GPS is hooked up to the PPC.

jb2001 · 10-04-04, 08:30 AM

I had the same dilema but eventualy opted for the CF card
here's my reasoning:

I have an X5 Advanced including BlueTooth CF card, Wifi CF Cards, 2GB CF cards etc etc. IMHO I didn't see the point of having to lug around my BT CF card & a BT GPS when I could get 1 item to do the job of 2. Also i'd need to lug about 2 chargers; 1 for Axim & 1 for BT GPS.

The CF card looked like the ideal solution for me, Oh and I'll also be able to use it when i get my X50 lol

PS Alot of threads recommend external arials for CF GPS but My Holux GM270 works GREAT without one.

Battery Life when driving = Unlimited (get a DC car charger)
Battery Life when Walking = 4 Hours ?? (get a spare axim batt)

JakeRich · 10-04-04, 10:21 AM

The Axim X5 draws about 210 mA in "normal" mode. The single heaviest draw on the Axim is the screen brightness. Setting that option to something full bright will significantly increase battery draw. That 210 mA figure comes from the observation that a 1440 mAh battery lasts just under 7 hours with a moderatly lit screen. Now, no two GPS CF cards, or BT CF Cards are exactly the same, but the Socket BT CF Card says it draws 40 mA, the Haicom 303 MMF GPS draws about 90 mA. So with a BT card, the Axim will experience about 250mA and with the Haicom 303MMF it experiences about 300 mA. The BT will theoretically exhaust the battery in 5.75 hours, the GPS in 4.8 hours. Of course, if you use a different BT card, or different GPS, the difference in power consumption will be more or less.

jb2001 · 10-04-04, 05:22 PM

for your info the Holux GM270 is 8o mA at 3.3V in Continuous Mode

The Rikaline GPS-6021-X6 sports 70 mA at 3.3V in Continuous Mode

But for the King of lowpower GPS CF cards The Rikaline GPS-6020 sports a whoping 29mA at 3.3V in Continuous Mode

I'm not sure about the performance of the Rikaline CF cards but the Holux card is excelent

Shoeminator · 10-05-04, 01:29 AM

Originally Posted by jb2001

for your info the Holux GM270 is 8o mA at 3.3V in Continuous Mode

The Rikaline GPS-6021-X6 sports 70 mA at 3.3V in Continuous Mode

But for the King of lowpower GPS CF cards The Rikaline GPS-6020 sports a whoping 29mA at 3.3V in Continuous Mode

I'm not sure about the performance of the Rikaline CF cards but the Holux card is excelent

Thanks guys,

I'm looking at GPS for the x50 (has BT internal) but that said, if there's little difference between the BT energy consumption and the GPS than, hmmm ..... might toss a coin :-)

there seem to be a lot of Holux 270's on ebay recently and they seem to be quite a bit cheaper than the BT versions, so I might go that way.

Thanks again

Cheers...

Shoei

jb2001 · 10-05-04, 09:30 AM

Shoei , it really is your preferance for either CF or Bt. I would think bluetooth would be the way to go if you have BT "built-in", it would then free up your CF port for a nice 2GB CF card

If your on a tight budget then the CF may be your answer