Sirfstar Iii Use On The Road

[+Alan2]

Anyone using this on the road for auto navigation? Are there delays in response so that it gives a reading a second or two after the actual location you were just at?

[kerecsen]

What software are you using?

[+Alan2]

Well, I don't have Sirfstar III but I'm thinking of buyingit. Currently I use Mapopolis with Fortuna CF slot GPS which is a dual sensitivity GPS. It's broken in the regular sensitive position. In the high sensitive position that's good for the woods, there's a 2 second delay so that when using on the road, where you're traveling pretty quickly, two seconds can often take you past the turn point until you get a prompt.

 

I'm concerned that the Sirfstar III might have the same delay and want to get some advice before I buy it.

 

Tks

[kerecsen]

I think I saw similar complaints on the gpspassion forums, but mostly linked to a particular hardware/software combination. I have also seen it with some software, but not with most, which leads me to conclude that it's not the GPS's fault (I have a holux sirf III unit)

 

Early sirf ii/xtrac chipsets did have a known lag, maybe you own one of these (http://www.gpspassion.com/fr/articles.asp?id=90&page=4)

[+Alan2]

Does anyone manufacturer a SIRFSTAR III to insert into a CF slot. That seems easier than dragging a separate bluetooth GPS into the woods with my PPC. How do you handle the Holux in the woods and in the car?

Edited October 16, 2005 by Alan2

[kerecsen]

Does anyone manufacturer a SIRFSTAR III to insert into a CF slot. That seems easier than dragging a separate bluetooth GPS into the woods with my PPC. How do you handle the Holux in the woods and in the car?

There are several CF Sirf III receivers out there (see http://www.semsons.com/comflasgpsre.html for some examples). However, you should seriously consider bluetooth if you are going to do hiking. You can put the bluetooth receiver into your backpack (or fasten it to your hat, or whatever), so it gets pristine reception, and keep the PPC in a convenient location where it would not get good reception but is easy to reach.

 

You will also have much better battery life (two batteries instead of one). (I get right about 10 hours of use out of both my PPC and the GPS.)

 

In the woods I put the Holux in my backpack, and in the car I just toss it in a recess of the dashboard (however it gets good reception even in the glove compartment, in the cupholder or on any of the passenger seats).

[+Alan2]

Do you use Mapopolis in the car and is there any delay? In the woods, do you use the PPC and you regular GPS or just the PPC with Holux? If both, how would you compare accuracy, etc? Which handheld GPS do you use? Tks again. Alan

[kerecsen]

I have never scrutinized the delay with Mapopolis. If there is one, it is slight enough that it never caused any noticeable (adverse or otherwise) effects. However, I would imagine that a slower PPC may cause problems that I wouldn't see (mine is a 400 MHz Qtek S110).

 

My primary software is iGo, I only use Mapopolis when I feel like experimenting.

 

I no longer use a handheld GPS. I used to have a 60cs, and the Holux is far-far better in time-to-first-fix and accuracy (especially under challenging conditions). I sometimes hike with a friend who has a 60cs and the Holux keeps a lock much more reliably and is more accurate. I base this on comparing the 60cs/Holux track logs to a really precise hiking map and also comparing the track on the way up the mountain to the track on the way down.

 

In addition, since I can put the Holux in my backpack, it gets better reception to begin with. I can't do the same with the 60cs, because then I would have to take my backpack off every time I wanted to look at the GPS. Unfortunately if I hung the 60cs off my belt, it basically wouldn't hold a lock at all (the Holux does a decent job even in my pocket). Of course this can be remedied to some extent with an external antenna or a re-radiating antenna.

[kerecsen]

Here is a tracklog comparison.

 

A typical 60cs log is slightly different on the way up and on the way down, and has some dropouts despite the fact that I had the GPS in my backpack (dropout is under "Spring"):

 

A typical Holux log is more consistent, and I have yet to see a dropout:

 

(Note that where the two tracks slightly diverge towards the peak (around 0.7 marking) I actually took two different paths.)

 

The map behind is the totally awesome "Wasatch Hiking Trails" by Daniel Smith. The author used a Trimble GPS with differential post-processing to survey the trails.

[+mlk3454]

I use a holux sirf III bluetooth unit with my PPC and I can't complain at all other than maybe if you need to charge either/both units you need a splitter for your cig lighter. Reception is wonderful for the holux unit and I usually keep it in the cd recess under my stereo unit. I use TomTom for software and there is no real noticeable lag. If there was anyways, there are enough reminders that a turn is coming up with TomTom that you shouldn't miss it anyways. Using the unit for hiking or caching with beeline is ok. I will stick with my 60C for that.

[+Alan2]

Well I bought and have been using the Globalsat BC337 CF GPS with the SirfStarIII for a few weeks now. There's no delay using Mapopolis and the accuracy and quick to lock is great. I haven't tried in in the canyons of Manhattan yet or under foliage but will report when I do. I paid 94 but the setup is already reduced to 84.00 http://www.semsons.com/bccoflgpsres.html

Edited January 5, 2006 by Alan2

[+Greymane]

The delay you are talking about comes from the static navigation feature. The device tries to prevent "hunting" by not updating at very slow speeds (like walking speed or approaching a red light). Many new units have this capability. Some come with it enabled, some disabled. If you unit has static navigation enabled and you use it for walking, it will be VERY sluggish. Turn it off, and it works just fine.

[+Greymane]

The Holux GPSmile 60 is a sweet unit. I have been testing one for a couple weeks now. It keeps a fix like nothing else I have used and has better battery life than my Axim. I love these SiRF III receivers.

[tossedsalad]

I am new to the idea of using a PPC with a GPS front end. I didn't realize so many people were using this rather than hand held GSPrs. When you use the term PPC, does that strictly mean Pocket PC or is that generic and includes Palms?

[+Alan2]

Pocket PC refers to Windows operating system. Palm operating system are refered to as PDA's I believe for the most part.

 

If you can picture your PC in miniature form with a screen twice the size of a Garmin 60 with GSAK and a GPS and Magellan or Mapsource program maps attached, or Natuional Geographic topo maps, all on the road or on the trail, you'll have a pretty good idea of what you get with a PPC. Now add an voice activated/visual promted auto-navigation system where you can auto route from cache to cache along with using it for games, telephone list, ToDO lists, and appt calender, well, the versatility doesn't end.

 

With the SirfStarIII GPS chipset, you have the quickest and most sensitive satellite locking, accurate GPS currently available.

Edited January 6, 2006 by Alan2