WASS no working?

August 31, 2003

What keeps me from getting a WAAS connection...I've left the GPS on for hours in a clear area, driven 250 miles (4 hours) with it on the dash, but sitll don't get a WAAS enabled session. I live in Minnesota...too far from the equator?

August 31, 2003

Equator has nothing to do with getting WAAS. Make sure your east and west sky are pretty clear near the horizon, i.e. no mountains or trees obstructing the view. There are two WAAS satellites, one over the west coast and one over the east. -----------------------------------------------------------

Garmin V

August 31, 2003

Checking some of the obvious things...

1) Is the unit WAAS enabled?

2) Is the WAAS feature turned on?

3) Do you have the latest firmware?

George

3.5k · August 31, 2003

It appears you Ique 3600 does have waas. Now you just have to turn it on (settings> enable WAAS)

"See the wonderous works of Providence! The uncertainty of human things!" Geo.Washington

1.4k · August 31, 2003

Does a Geko 201 accept more then just WAAS? I've gotten the "D" indicator in Hawaii and in Japan. So either I'm picking up something else or WAAS covers a lot more then just CONSUS.

1.1k · August 31, 2003

quote:
Originally posted by GeckoGeek:
Does a Geko 201 accept more then just WAAS? I've gotten the "D" indicator in Hawaii and in Japan. So either I'm picking up something else or WAAS covers a lot more then just CONSUS.

The satellite signal coverage/footprint does but the corrections do not.

I believe the latest software version corrects this little oversight in the software as now that ENGOS is in test mode if one is not within in the actual correction zone then the unit will not use WAAS/EGNOS etc.

The problem was if one was outside the correction zone one could receive the geo sats but WAAS reception actually destroyed accuracy.

Cheers, Kerry.

I never get lost everybody keeps telling me where to go

[This message was edited by Kerry on August 31, 2003 at 10:20 PM.]

1.1k · August 31, 2003

quote:
Originally posted by volks_ev71:
Equator has nothing to do with getting WAAS. Make sure your east and west sky are pretty clear near the horizon, i.e. no mountains or trees obstructing the view. There are two WAAS satellites, one over the west coast and one over the east.

The equator? well it does really as geo satellites, which is what WAAS satellites are are basically directly over the equator. So east or west would only be (really) relevent if one was actually at equator latitudes but then one would be outside the WAAS correction area anyway.

The further one moves north (away from the equator) then the WAAS satellites are more South-east (actually more south from the US east coast) and south-west as one is over the east coast of Brazil and the other in the western pacific.

Cheers, Kerry.

I never get lost everybody keeps telling me where to go

3.5k · August 31, 2003

Yes, WAAS does work over Hawaii. Not only does it lie within the sat footprint, but it has a correction station on which it (in this case) relies. The 178E is sat # 47 and is at lat0/long178E. You can pick up this same sat in Japan but there it would be of no use at this time.

"The master station will generate correction data or each of the grid points tagged in the mask. A receiver will locate its position relative to 4 grid points and interpolate the data from those 4 points based on their relative distance. If only 3 points have data then the receiver will compute a triangle of the 3 points and if it is inside the triangle it will use the 3 points to interpolate its correction. Otherwise, the use of any of the grid points for correction is undefined. It seems however that most gps implementations will use the data from even a single point if it is "close" to the current location. As can be seen from the map of the US phase I implementation this is required to provide WAAS for areas such as Alaska and Hawaii. It may be that multiple grid locations are generated from the single data input."

1.4k · September 1, 2003

quote:
Originally posted by Kerry:
The equator? well it does really as geo satellites, which is what WAAS satellites are are basically directly over the equator.

I had to double-check your statement. WAAS signals are carried on geo-stationary satellites. (The GPS sats are NOT geo-stationary.)

Geo-stationary units are always over the equator since there's no other way to make them orbit the earth and make them appear stationary.

It should be noted that WAAS was primary made for airline navigation. As such being able to “see” the equator isn’t usually a problem.

1.4k · September 1, 2003

quote:
Originally posted by EraSeek:
"The master station will generate correction data or each of the grid points tagged in the mask. A receiver will locate its position relative to 4 grid points and interpolate the data from those 4 points based on their relative distance. .....

I think I got that. Thanks. Where do I find a good explanation of WAAS in plain language?

2.9k · September 1, 2003

I think that the original poster, being in Minnesota, means that the WAAS birds are too low to the Horizon. Im in Detroit Michigan and lose the WAAS birds whenever I go past buildings or trees. If I were in Florida, the WAAS bird would be high enough, that obstructions would not matter much. Thats what he meant by being too far from the equator, that the birds are too low to the horizon.

Question: If I were in MiniApples MiniSoda, What would be the bearing and elevation of WAAS bird meant for the Eastern USA, and the bird meant for the Western USA ??

2.9k · September 1, 2003

Example using my Dish Network Satellite Reciever Setup Screen:

My HOME position = N42.5º - W83.3º

Dish Network Satellite is W 119º over the equator.

Azimuth Angle(bearing) = 223º

Elevation Angle = 34º

3.5k · September 1, 2003

If you were in Minnasota you would only get Sat #35, and not 47. Sat 35 will still do you find. I know you can find how high and the bearing on line but I am north of Seattle, just as far North as he, and I get them both often even though they are somewhat low.

WAAS is a system of satillites and ground stations that analize things such as ionosphere activity which can delay your signal from the sats and throw your position off. Data is sent down from the sats, analized and sent back to the sats and then to your GPS to correct for these errors for the area that you are in on the modeled grid. Also corrected are timing error and troposheric errors as well as a few other things. With a good signal and enough time to load the information you GPS will correct your position to with in about 3meters 95% of the time.

[This message was edited by EraSeek on September 01, 2003 at 08:10 AM.]

2.3k · September 1, 2003

I'm in Sweden (N57º) and I can still receive Egnos signals, provided the view is reasonably clear towards the equator.

The Japanese MSAS system is designed to use non-geostationary satellites for the overlay information, I've read.

Anders

September 1, 2003

Thanks all for the ideas...and yes, my reference to Minnesota and the equator was concern that this location is too far north to get the signal...sounds like Sat 35 should be viewable though...I'll check for it again, however it still makes me wonder why it hasn't shown up yet...I sent a note to Garmin tech support as well to see if they have some ideas...

Mark

3.5k · September 1, 2003

Now here is a link I do not totally understand yet: http://www.nstb.tc.faa.gov/vpl.html but if I understand it correctly, it is showing at what verticle level Waas is useful in the WAAS service area. If that is so, then this is a really great map of where WAAS is, and how good a signal you have there.

On the Minnisota question, remeber the can get WAAS in Alaska too. The are rather far North than you. (Well, maybe you have to be in a plane)

"See the wonderous works of Providence! The uncertainty of human things!" Geo.Washington

1.4k · September 1, 2003

quote:
Originally posted by mdh01:
I'll check for it again, however it still makes me wonder why it hasn't shown up yet...I sent a note to Garmin tech support as well to see if they have some ideas...

Check your unit's setup. You didn't say what model you had, but on my Garmin the mode was set to "Normal" out of the box, which turns out to mean WAAS is off. Confusing.

1.1k · September 1, 2003

quote:
Originally posted by GeckoGeek:

quote:
Originally posted by Kerry:
The equator? well it does really as geo satellites, which is what WAAS satellites are are basically directly over the equator.

I had to double-check your statement. WAAS signals are carried on geo-stationary satellites. (The GPS sats are NOT geo-stationary.)

Geo-stationary units are always over the equator since there's no other way to make them orbit the earth and make them appear stationary.

It should be noted that WAAS was primary made for airline navigation. As such being able to “see” the equator isn’t usually a problem.

GeckoGeek, I've read that and read it several times more looking for whatever issue you are trying to outline or "double-check".

But going back to the previous overall post the comments were in relation to this thinking that one must have a clear view to the EAST and/or WEST, which is simply not the case.

Cheers, Kerry.

I never get lost everybody keeps telling me where to go

September 1, 2003

I checked the Garmin IQUE 3600 for WAAS and it has a box to check to enable it...the box is checked, but I tried it checked and unchecked and it doesn't seem to matter...

1.1k · September 1, 2003

quote:
Originally posted by EraSeek:
... WAAS is a system of satillites and ground stations that analize things such as ionosphere activity which can delay your signal from the sats and throw your position off. Data is sent down from the sats, analized and sent back to the sats and then to your GPS to correct for these errors for the area that you are in on the modeled grid ....

That reads to me (impression) that the WAAS "sats" (themselves) do the analyzing but the WAAS geo's are primarily simply a communication/re-broadcast satellite, even thou the WAAS geo's (inmarsats) can be enabled to act as additional pseudo "GPS sats".

Maybe if the 2 different types of sats were specifically tagged it would make for a better impression.

Basically all the WAAS geo's do is transmit the corrections as for there to be corrections the user must have GPS satellites in view that are also being tracked by 4 WAAS ground stations.

"....Data is sent down from the sats, analized and sent back to the sats and then to your GPS to correct.... "

Data is received from the GPS sats (by the ground stations), analyzed and corrections sent back via the WAAS geo's then to your GPS to correct etc

Cheers, Kerry.

I never get lost everybody keeps telling me where to go

1.4k · September 1, 2003

quote:
Originally posted by Kerry:
GeckoGeek, I've read that and read it several times more looking for whatever issue you are trying to outline or "double-check".

First, I had to double check for myself that WAAS is carried on a geo-stationary sat because GPS sats are clearly not geo-stationary.

Second, I had to make sure I understood what you ment by "geo stat" since "geo" could mean a lot of thing in this forum.

I think we all agree that the further north you go, the lower on the horizon one must have a clear view in the direction of the sat.

2.9k · September 1, 2003

quote:
But going back to the previous overall post the comments were in relation to this thinking that one must have a clear view to the EAST and/or WEST, which is simply not the case.

Cheers, Kerry.

I have run several tests with WAAS enabled GPS units, and always lose the "D"s in the signal strenght Bars on the sat page, whenever there are obstructions or im facing in a different direction, WAAS sat number 35 unhighlights and the "D"s disapear.

2.9k · September 1, 2003

If Sats 35 or 47 not showing up, then there is a problem with your Ique 3600, especially if you already have an external antenna on your car's roof.

I have tried WAAS on a Vista, GPS V, Map 76, and my MeriPlat

1.1k · September 1, 2003

GeckoGeek, ok I understand your comments now. I suppose "WAAS geo's", which is a term commonly used for them would be better termed "WAAS Geo-stationary" as opposed to the GPS sats being Geo-centric.

For this reason as they don't move (the WAAS geo stationary satellites that is) and probably similar to GOT GPS's comment if one doesn't have a WAAS signal due to low horizon, obstructions etc then no amount of waiting will ever change that condition.

Probably said this many times before but for best possible reception from a handheld then one should actually face the direction of the equator. With straight GPS this is important as there's no satellites over the poles and secondardly with WAAS it's even more important (to face the actual direction of the WAAS geo) that there's nothing between the antenna and the direction of the WAAS Geo-stationary sat/s.

Cheers, Kerry.

I never get lost everybody keeps telling me where to go

3.5k · September 1, 2003

No. I did not mean that. You are right Kerry the sats are not doing the analyzing. Their signals are analyzed by the ground sations for signal delay and such and the ground stations model a correction grid and broadcast these corrections through the WAAS sats.

"See the wonderous works of Providence! The uncertainty of human things!" Geo.Washington

1.4k · September 1, 2003

quote:
Originally posted by Kerry:
With straight GPS this is important as there's no satellites over the poles ..

Now I'll have to go back and find out what kind of orbit the GPS sats are in. I thought the pattern was to cover all of the earth fairly well. I'd have thought the polar reagion would have been well covered since "the red menance" was still much of a design consideration and navigating near the poles is a real pain.

September 1, 2003

quote:
Originally posted by nincehelser:
Checking some of the obvious things...

1) Is the unit WAAS enabled?

2) Is the WAAS feature turned on?

3) Do you have the latest firmware?

George

4) Make sure you're not in "battery saver" mode. (I learned this the hard way. I went for a few months as a newbie thinking I was receiving WAAS on my Vista.)

1.1k · September 1, 2003

quote:
Originally posted by GeckoGeek:
Now I'll have to go back and find out what kind of orbit the GPS sats are in. I thought the pattern was to cover all of the earth fairly well. I'd have thought the polar reagion would have been well covered since "the red menance" was still much of a design consideration and navigating near the poles is a real pain.

GPS has 6 orbital planes inclined at 55 degrees with room for 5 satellites (slots) in each plane. GPS sats are Geo-centric orbits earth-centred and are basically circular.

GPS satellite coverage if one was at either of the poles would look like this

everybody keeps telling me where to go

3.5k · September 1, 2003

Yes, there is a polar cap on satellite postions. But, yes, you do have gps coverage at the poles as demonstrated HERE

Also, here is another shot of the sats ground tracks:

2.3k · September 2, 2003

Being in southern Sweden, I frequently notice that I do use all twelve channels of my receiver. This is something that's rather rare for people in the main US, I've understood from this (and other) forums.

But as pointed out above, and clearly visible from the coverage maps, we can both use some sats that are "on the other side" and since the sats (appears to) turn back over our latitudes, not just pass by, they are visible for a longer time over our heads.

As far as WAAS (or Egnos in my case) reception, I've very rarely been able to establish such a connection with a fresh start (i.e. without any almanac data for the augmentation satellites in the unit) whilst I've been rambling around on the ground. The reception comes and goes, which means that the consistent data download time that's required for the augmentation to be completed hardly exists.

I did like this: I placed my Vista inside a window in my house. This window I knew would have a good view of IOR. After half an hour there, I looked at it, and it had indeed loaded sat data for the augmentation sats visible here, i.e. IOR and AOR-E.

Now, once that has been done, it usually doesn't last more than 10-20 seconds after turning WAAS on, before I get a signal from one or both of the Egnos satellites. Provided they can be seen from my location, of course.

Garmin receivers (at least most of them) can operate in two basic modes: Normal and battery save. The position update rate is once every second in normal mode, but once every 3-4 seconds in battery save mode. Additionally, WAAS can be enabled or disabled separately. Enabling WAAS in battery save mode has no effect, due to the nature of the WAAS transmissions. WAAS works only when measuring every second.

If the unit (at least my Vista) is powered externally, it automatically uses Normal mode, regardless of the setting. So, if you have battery save mode and WAAS enabled and then apply external power, it will change to Normal mode and start using WAAS. As soon as the external power disappears, it will go back to battery save mode and stop using WAAS (and turn itself off, unless you confirm manually that you want to run on the battery supply).

Anders

[This message was edited by Anders. on September 02, 2003 at 12:49 AM.]

September 2, 2003

Hey,

I'm in the Minneapolis area. I've got a Garmin etrex Vista. If your receiver is like mine, make sure WAAS is ENABLED. Takes some button pushing and clicking around to do so.

I've had no trouble. Typically, within the city/built up area, I'll get around 18-25'accuracy. Likely due to buildings, trees, etc blocking the horizon. When I've had it on the dash of my car and am driving outside the Metro area (Mankato, Worthington, SW Minnesota, for example), it's gotten as good as 7'accuracy.

So, it has nothing to do with being in Minneasota. It's either your receiver or the local environment preventing a perfectly clear view.

September 2, 2003

WAAS works by measuring the time it takes for a signal sent from a satellite to reach a GPSr. This is the propagation delay. Propagation through the atmosphere is different and, because of weather conditions, less predictable than propagation through the vacuum of space.

If you were on the Equator your WAAS signal is striking the atmosphere at a 90 degree angle so there is little atmospheric distortion. As you move North, the angle of "attack" increases so your signal gets more and more distorted the further North you may go.

I guess what I'm trying to say is that even if you are getting a WAAS signal it doesn't necessarily mean that it is really helping your accuracy.

I had to edit this post. Everything in bold above is the original post and is just about as wrong as it could be. Thankfully, Blindleader pointed out the errs of my way (or the errors in my WAAS understanding). I don't know how I had developed such a wrong impression of how WAAS works but the links that Blindleader forwarded to me really helped show me the light. I hope I didn't cause problems for anyone. I'll be more careful in the future.

Ducks - Flying, great tasting, geocaches of meat

[This message was edited by Rubberhead on September 03, 2003 at 02:34 AM.]

[This message was edited by Rubberhead on September 03, 2003 at 02:36 AM.]

2.3k · September 2, 2003

Well, Rubberhead, I think you mean right, but as you put it, it can very easily be misunderstood.

Augmentation systems (differential GPS) works by determining the position of a ground station, and then compare that to the known position of this station. Since it's a fixed building, it should be on the same, very precisely determined, position all the time.

Due to distortions of the signal in the ionosphere and troposphere (and more), the calculated position will differ from the real position. This is why it's called a differential system. For each GPS satellite, the system will then calculate a correction that should be applied to that signal. This correction is different depending upon where you are on the earth, since the signals will pass different parts of the sky above you. Hence, there are several ground stations, spread out over the covered area. The result is a grid of measured correction points. This grid is then interpolated to figure out the appropriate correction at the particular place where your receiver is.

Distributing these corrections can be done in different ways. The older method is to use some ground-based transmitter, like an FM radio network. That method implies that the GPS receiver has two different antennas, since FM is a very different frequency, compared to GPS.

The method used by SBAS (Satellite Based Augmentation Systems, like WAAS) is to transmit these corrections from the ground to special augmentation satellites. These satellites then send the data back down again, to the receivers. The receivers in turn uses the information to calculate which corrections should be applied to the different GPS satellites for which correction data has been received. With a Garmin unit, that's indicated by the famous 'D' in the signal strength bar.

Since these signal are sent with the same frequency as the regular GPS signals, they can be received with the same antenna in the receiver. No need to carry large and clumsy additional receivers around.

The correction data will, when appropriate, be applied at a grade that depends on the angle relative to ground for the signals (the elevation of the satellite, from a ground point of view).

The signal from the augmentation satellite can also be used for positioning, and can be differentially corrected as well.

Anders

September 2, 2003

I'm also in the Twin Cities area and have a Meridian Gold and a Garmin Venture. Both have no trouble with getting a WAAS lock, but the Meridian is faster and can hold it better.

- Dave

3.5k · September 2, 2003

Here is that simple explanation someone was looking for: http://gps.faa.gov/programs/index.htm

Also, Yes rubberhead, sometime even though you are recieveing WAAS it may not help your position because there may be little or no corrections to be made. At night, for instance, there is much less ionosheric disturbance, thus, less signal delay. So plant your caches at night for the best coords.

"See the wonderous works of Providence! The uncertainty of human things!" Geo.Washington

3.5k · September 2, 2003

Here is a moving graph of how the ionosphere is active throughout the day:

http://gpsinformation.net/exe/iono-day.gif

3.5k · September 2, 2003

Here is where you can track WAAS sat 35 and find it's position in relation to your position. Just click the spot on the map where you are:

http://www.lyngsat.com/tracker/inmar3f4.shtml

"See the wonderous works of Providence! The uncertainty of human things!" Geo.Washington

September 2, 2003

Anders,

I appologize. I do try to make oversimplification an art form. I do this because it's the only way my pea brain can handle complex issues.

Ducks - Flying, great tasting, geocaches of meat

2.3k · September 3, 2003

Simplifying complex things is a delicate art. Still, one has to keep the essential things in the explanation, or it will be even more confusing.

Anders

September 3, 2003

Not only had I simplified things - I had them almost totally wrong. Blindleader send me a nice e-mail pointing out how wrong I was. He was nice enough to do it privately but I still need to try to clean up any misunderstandings that I've caused.

I've edit my above explaination of WAAS - I didn't try to re-explain it, I simply marked my explaination as horribly wrong.

Sorry - I'll be more careful in the future.

Ducks - Flying, great tasting, geocaches of meat

1.2k · September 3, 2003

quote:
Originally posted by mdh01:
What keeps me from getting a WAAS connection...I've left the GPS on for hours in a clear area, driven 250 miles (4 hours) with it on the dash, but sitll don't get a WAAS enabled session. I live in Minnesota...too far from the equator?

With all this rambling, did you ever get WAAS working? Has it ever work on you GPSr?

I had a similiar problem with my etrax legend. I reset it several time and pointed the device towrds the WAAS sats in the SE, what I ended up doing was reinstalling the firmware. It was a matter of seconds from the time I turned the GPS on, that the WAAS sats came in.

Good luck.

2.3k · September 3, 2003

Hmm, that kind off implies that I wasn't kind, when I responded in public. I hope you weren't offended that much...

Anyhow, since I didn't get any e-mail from Blindleader, it seems that he considered my description accurate enough. It's easy to get the wrong impression about how these things work, since they are rather convoluted. That's why these forums are good, because there is always somebody who knows. If nothing else, Kerry starts nagging when something technical is off road.

Anders

September 3, 2003

quote:
Originally posted by mdh01:
What keeps me from getting a WAAS connection...I've left the GPS on for hours in a clear area, driven 250 miles (4 hours) with it on the dash, but sitll don't get a WAAS enabled session. I live in Minnesota...too far from the equator?

I just tested it last night (after reading the instruction manual for my eTrex Vista). I live in Burnsville (South of Minneapolis) and I had no problem picking up Sat. 35 and getting a 17ft. accuracy with WAAS. It did take about 2 mins to lock on to 35 and get the indication that WAAS was enabled.

So it DOES work in Minnesota. I just don't know about Northern MN. When I make a caching trip to Duluth I will test it higher up there

Silent Bob.

September 3, 2003

quote:
Originally posted by Anders.:
Hmm, that kind off implies that I wasn't kind, when I responded in public. I hope you weren't offended that much...

I've been married to the same woman for 17 years. At this point, I am unoffendable. I really didn't mean to imply anything but that I was total off-base about how WAAS works.

Ducks - Flying, great tasting, geocaches of meat

1.1k · September 3, 2003

quote:
Originally posted by Anders.:
Hmm, that kind off implies that I wasn't kind, when I responded in public. I hope you weren't offended that much...

.... If nothing else, Kerry starts nagging when something technical is off road.

Nagging , now that's a qaint way of putting it.

But yes I did notice things were a little lost but you had already remedied the situation fairly well I'd thought, so didn't have to nag

Cheers, Kerry.

I never get lost everybody keeps telling me where to go

September 3, 2003

Lot's of interesting feedback...throughout all this, I still haven't seen WAAS work on the IQUE3600...Garmin Tech support provided the following:

"Being in Minnesota you may have a hard time acquiring it, but that doesn't

mean that every once in awhile that it will acquire for you. The satellite

is located around the equator south of Florida and therefore can be hard to

acquire that far north. To acquire it your best chance would be to have the

antenna pointed South to Southeast. If you go to the satellite acquisition

page it will be satellite #35 on your screen to see if it is trying to get a

lock on it or not. Garmin Tech Support"

I continue to try, but also have accepted that it just may not work out...for routing on roadway's it isn't a problem...I was hoping for better accuracy when ice fishing in Minnesota, or other activities requiring more pinpoint accuracy, etc....

1.1k · September 3, 2003

The theorical elevation (barring all obstructions) through out Minnesota, ranges from 20 (SE corner) to 29 degrees (NW limits).

However attempting to use WAAS in the type of application that many try to use it, has to accept the fact that WAAS was never designed for land based activities. It appears to have become more a marketing tool than anything that is guaranteed.

One simply shouldn't have to reset, reboot or re-install software and wait ages for a system like this to work. My perception is WAAS installed on a handheld is out of its depth, out of its intended evnironment and application and a low end handheld simply doesn't have the processor power (or antenna design) for it to be more than a gizmo.

Cheers, Kerry.

I never get lost everybody keeps telling me where to go

5.3k · September 3, 2003

quote:
Originally posted by Kerry:
My perception is WAAS installed on a handheld is out of its depth, out of its intended evnironment and application and a low end handheld simply doesn't have the processor power (or antenna design) for it to be more than a gizmo.

You've expressed this opinion before, and it continues to puzzle me. I have measured a significant, reproducible performance improvement for my little handheld GPS unit using WAAS. It doesn't take very long in my area for the WAAS satellites to lock in and for the corrections to be applied.

Sure, it doesn't work for everyone everywhere, but such expectations would be unrealistic. It does make a significant difference for me, and I think that dismissing it as marketing hype is inappropriate.

September 3, 2003

quote:
Originally posted by Kerry:
My perception is WAAS installed on a handheld is out of its depth, out of its intended evnironment and application and a low end handheld simply doesn't have the processor power (or antenna design) for it to be more than a gizmo.

As far as I know the Garmin units ALL use ARM-based processors (the iQue has a 200mhz ARM) I am unable to locate the mhz rating for a Garmin eTrex Vista.

Explain to me how it doesn't have the CPU power to handle GPS (when the other Garmin units are using the same architecture)?

Before I received my Garmin eTrex I would have agreed that the antenna in the iQue might be inadequate. I have found ABSOLUTELY NO PROBLEMS with the internal antenna in the Vista, in fact, I am usually accurate to 20ft or under even with heavy tree cover...

That's my worthless .02

Silent Bob

1.1k · September 3, 2003

Silent Bob (& Fuzzy), with relation to antenna's the issue with handhelds (and built-in antenna) is they can be pointed any which way and actually if handhelds weren't detuned as far as signal recpetion was concerned many wouldn't maintain a WAAS lock for more than a few seconds. An external antenna in most cases would make one hell of a difference to reliable WAAS reception, assuming suitable reception and of course not everybody does get suitable signal reception.

Really the recreational side of WAAS software doesn't take into account the full capabilities of WAAS and it wasn't all that long ago that receivers marketed as supposedly 1 second position updates, simply couldn't achieve that claim either.

Even quickly looking at output these days it appears 1 second update but it's more like a 1 second output, with the same computed position output for several/many seconds in a row.

That simply points to lack of processor power (or basically priority being directed to the primary purpose of a GPS receiver, position, position, position) in many cases but things are getting bigger and better but at a cost and cost is what most manufacturers have to keep down. Sure manufacturers could pack a wack of power into a handheld but not many would be sold compared to other models. Bit of a compromise, processor power, battery power/life and cost.

Similar with displayed time, a recreational GPS receiver doesn't give much priority (really at all) to worrying what the time is, if it's a few seconds out nobody really cares.

Cheers, Kerry.

I never get lost everybody keeps telling me where to go

WASS no working?

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