[gps-talkusers] Re: THe earthmate:
- From: "Chip Orange" <Corange@xxxxxxxxxxxxxxx>
- To: <gps-talkusers@xxxxxxxxxxxxx>
- Date: Mon, 7 Jun 2004 14:28:59 -0400
If you are in north America, and your receiver is WAAS capable, and your
receiver has had a fix for 5 minutes or longer, then you should be able
to assume you've got 3 meter accuracy. It won't always be the case, but
there's a way for the GPS to tell you how likely it is that you do have
3 meter accuracy at the moment (it's called the HDOP, or horizontal
dilution of position). I don't know if the Sendaro product uses this
number when their software gives you an estimate of your fix quality,
but if they do then you would have a way at least of knowing how much to
trust your unit at that moment. This number is kind of like a
measurement of uncertainty as to the position report being given.
Chip
=20
> -----Original Message-----
> From: gps-talkusers-bounce@xxxxxxxxxxxxx=20
> [mailto:gps-talkusers-bounce@xxxxxxxxxxxxx] On Behalf Of lazzaro
> Sent: Monday, June 07, 2004 2:18 PM
> To: gps-talkusers@xxxxxxxxxxxxx
> Subject: [gps-talkusers] Re: THe earthmate:
>=20
> If we could reliably get 3 meter accuracy, I could live with that.=20
>=20
>=20
> -----Original Message-----
> From: gps-talkusers-bounce@xxxxxxxxxxxxx
> [mailto:gps-talkusers-bounce@xxxxxxxxxxxxx] On Behalf Of Chip Orange
> Sent: Monday, June 07, 2004 9:11 AM
> To: gps-talkusers@xxxxxxxxxxxxx
> Subject: [gps-talkusers] Re: THe earthmate:
>=20
>=20
> I have to ask though, isn't 3 meter accuracy good enough? =20
> Or, if you're not in north America, I guess it's 15 meter=20
> accuracy for the moment, although that will change in Europe soon.
>=20
> Like I said, this kind of esoteric question really should be=20
> asked on the news groups I mentioned; perhaps someone there=20
> will know more.
>=20
> Hth,
>=20
> Chip
>=20
> =3D20
>=20
> > -----Original Message-----
> > From: gps-talkusers-bounce@xxxxxxxxxxxxx=3D20
> > [mailto:gps-talkusers-bounce@xxxxxxxxxxxxx] On Behalf Of lazzaro
> > Sent: Friday, June 04, 2004 6:46 PM
> > To: gps-talkusers@xxxxxxxxxxxxx
> > Subject: [gps-talkusers] Re: THe earthmate:
> >=3D20
> > I was under the impression, perhaps mistakenly, that there=3D20 =
were=20
> >professional portable GPS receivers that might increase=3D20 the=20
> >accuracy of the system. =3D20 =3D20 -----Original Message-----
> > From: gps-talkusers-bounce@xxxxxxxxxxxxx
> > [mailto:gps-talkusers-bounce@xxxxxxxxxxxxx] On Behalf Of Chip Orange
> > Sent: Friday, June 04, 2004 8:48 AM
> > To: gps-talkusers@xxxxxxxxxxxxx
> > Subject: [gps-talkusers] Re: THe earthmate:
> >=3D20
> >=3D20
> > This is the kind of question that belongs on the news groups=3D20 =20
> >alt.satellite.gps and sci.geo.satellite-nav.
> >=3D20
> > My understanding that what you're refering to as a "pro" unit=3D20 =20
> >costs many thousands of dollars, and must remain=20
> stationary=3D20 in one=20
> >place for a very long period of time to get a very=3D20 =20
> accurate fix. I=20
> >think they may require the deployment of=3D20 multiple=20
> antennas as well. =20
> >It's nothing that really would=3D20 apply to us and our needs here.
> >=3D20
> > Most of the time, with WAAS working (which does take up to 5=3D20 =20
> >minutes after starting the receiver, and is currently only=20
> in=3D20 north=20
> >america) the accuracy is less than 3 meters. It's not=3D20 likely=20
> >you'll need more accuracy than that, so what would you=3D20 =20
> want out of=20
> >a "pro" unit that you're not getting at the moment?
> >=3D20
> > The only other thing I can think of is that there are=20
> units=3D20 which=20
> >have accelerometers built-in as well, which they use as=3D20 =20
> part of a=20
> >"dead-reckoning" system for the times when they=3D20 lose the=20
> satellite=20
> >fix.
> >=3D20
> > These are meant for people on the move, but again are many=3D20 =20
> >thousands of dollars.
> >=3D20
> >=3D20
> >=3D20
> > Chip
> >=3D20
> > =3D3D20
> >=3D20
> > > -----Original Message-----
> > > From: gps-talkusers-bounce@xxxxxxxxxxxxx=3D3D20
> > > [mailto:gps-talkusers-bounce@xxxxxxxxxxxxx] On Behalf Of lazzaro
> > > Sent: Thursday, June 03, 2004 7:38 PM
> > > To: gps-talkusers@xxxxxxxxxxxxx
> > > Subject: [gps-talkusers] Re: THe earthmate:
> > >=3D3D20
> > > I'm interested in using other receivers because we'd like=20
> to=3D3D20=3D20
>=20
> > >explore so called pro units. We're not even sure if the=3D20
> > pro=3D3D20 models=3D20
> > >have higher accuracy. Is there a site that compares=3D3D20 =
the=3D20
> > efficiency=3D20
> > >of GPS receivers so one can do a comparison? =3D3D20 =3D3D20 =3D
> -----Original=3D20
> > >Message-----
> > > From: gps-talkusers-bounce@xxxxxxxxxxxxx
> > > [mailto:gps-talkusers-bounce@xxxxxxxxxxxxx] On Behalf Of=20
> Chip Orange
> > > Sent: Thursday, June 03, 2004 4:01 PM
> > > To: gps-talkusers@xxxxxxxxxxxxx
> > > Subject: [gps-talkusers] Re: THe earthmate:
> > >=3D3D20
> > >=3D3D20
> > > Mike will have to answer that one; my guess is that they =
are=3D3D20=20
> > >=3D20 giving some special initialization command to the=3D20
> > SportTrack=3D3D20 that=3D20
> > >they don't give to any other model.
> > >=3D3D20
> > > While the BN may work with any GPS receiver, Sendaro=20
> would be=3D3D20=20
> > >=3D20 taking on a lot of extra support issues if they made=20
> that=3D3D20=3D20
> > claim. =3D20
> > >The earthMate is particularly easy for a blind person=3D3D20 =
to=3D20
> > deal with,=3D20
> > >but I bet there are models out there which aren't.
> > >=3D3D20
> > > If I were buying a receiver to go with the BN product, =
I=3D3D20=3D20
> > wouldn't=3D20
> > >buy anything other than what Sendaro recommended=3D3D20 =20
> without a very
>=20
> > >=3D
>=20
> > >strong reason; and I would do it with the=3D3D20 =
understanding=3D20
> > that I may=3D20
> > >run into issues that are difficult=3D3D20 to deal with.=20
> =3D3D3D20 =3D3D20
>=20
> > >=3D
> That=3D20
> > >being said, maybe you've got a good enough reason so=3D3D20 =20
> that armed
>=20
> > >=3D
>=20
> > >with the knowledge that all GPS receivers output=3D3D20 the=20
> same data,
>=20
> > >=3D
>=20
> > >you'd be willing to try one for some special=3D3D20 reason. =3D20
> > For instance,=3D20
> > >you may want to share one with a=3D3D20 sighted spouse, so the=20
> > >spouse=3D20 picks it out for its nice color=3D3D20 display=20
> and maps or=20
> > >some other=3D20 reason. =3D3D20 Hth, =3D3D20 Chip =3D3D20 =
=3D3D3D20 =3D3D20
> > > > -----Original Message-----
> > > > From: gps-talkusers-bounce@xxxxxxxxxxxxx=3D3D3D20
> > > > [mailto:gps-talkusers-bounce@xxxxxxxxxxxxx] On Behalf Of=3D3D20
> > > joe j lazzaro
> > > > Sent: Thursday, June 03, 2004 4:22 PM
> > > > To: gps-talkusers@xxxxxxxxxxxxx
> > > > Subject: [gps-talkusers] Re: THe earthmate:
> > > >=3D3D3D20
> > > > If the Sendero/Humanware BrailleNote GPS system is=3D3D20
> > > compatable=3D3D3D20 with
> > >=3D3D20
> > > >other receivers, I'm wondering why there are only=20
> two=3D3D3D20 =3D3D20
> > > listed on the
> > >=3D3D20
> > > >menu? If I were to use another unit not listed=3D3D3D20 =20
> on the=3D3D20
> > > menu, which=3D3D20
> > > >receiver should this be set to? =3D3D3D20 =3D3D3D20 Joseph=20
> J. Lazzaro=20
> > > >=3D
> =3D3D20=3D20
> > > >HTTP://JoeLazzaro.Com =3D3D3D20 =3D3D3D20 =3D3D3D20 =3D3D3D20
> > >=3D3D20
> > >=3D3D20
> > >=3D3D20
> >=3D20
> >=3D20
> >=3D20
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