Worth replacing an 8-year old GPS ?

I’m using an 8-year old Garmin GPSMAP 295, originally used for aviation, for my first steps in OSM-ing. I’m recording tracks but don’t know how accurate they are because I don’t have a gold standard to compare with. The 295 also uses batteries up very quickly as its screen technology is old and hogs electricity. That limits forays on foot or bicycle.

One question that went through my mind is whether the precision of this 8-year old GPS compares well with modern-day devices. Put another way, if I were to spend €500-1,000 on a new device would I get any more precision for my money ?

Clearly I can read reviews of current GPS devices on the WWW (and have to weed out those reviews that are paid for directly or indirectly by manufacturers) but they do not tell me whether the new devices are better that my existing one.

Is there a technically-experienced person here who can advise ?

Paddy

Of course, just in the years since Openstreetmap have been around things have really moved forward. But things have improved most in the €50-100 range, I believe the the high end devices are probably more or less the same as some years ago. Now I might be blowing smoke our of my ass, because I really don’t know anything about high end devices, but my feeling is that the cheapest stuff improve the most.

You could always try to get a Trimble, if you want a good GPS.

Well, ofcourse I can’t tell you that e.g. a Garmin eTrex Venture HCx will be ‘better’, but this receiver will probably be able to track more satellites at once then your old one, and have a better antenna too. These will significantly improve reception under heavy tree cover or in the urban canyons. Then there’s the color screen coupled with micro-SD card storage which would be pretty hard to find 8 years ago as well. This receiver will set you back a tad bit less then €200 if you look around.

So depending on the class your receiver was 8 year ago (budget, high-end), a new device will work much better especially where receiption is difficult and it has other nice features. But in the end it’s up to you to decide. Perhaps you can hire a new GPS for a day or so and try it out.

Thanks for these tips.

My Garmin 295 was at the very high end of the price range for a “consumer” GPS 8 years ago, partly because it is an aviation version. Around €1,800 at the time. The storage cards are proprietary Garmin and the colour screen is one which remains readable in the strong background daylight in an airplane cockpit so it consumes quite a bit of current. The software is from 2003 and hasn’t been updated by Garmin since then so I presume that it lacks improvements that have taken place in the GPS technology world since then.

Your mention of the Garmin eTrex Venture HCx is appreciated. I’ve been reading GPS reviews but most of the “consumer” GPS devices seem to be pitched at the car driver who wants to find the way to the nearest McDonalds with voice instructions and I’m not interested in that baggage. I want an accurate GPS for mapping and perhaps an occasional position finding when I’m on foot in the mountains but I don’t need a colour screen or expensive proprietary map data or a lady’s voice telling me where to go.

Re. precision, I guess a new GPS should be WAAS-compatible. Are there any other “added-precision” features which it should have ?

emj mentioned Trimble but they are way outside my wallet (but I’d love to have one).

Paddy

Well the thing is it all depends, the software on the cheap models can make up for a bad antenna. But I haven’t seen any big difference between my cheap datalogger Garmins. I would go for a Nokia N810 + GPS logger, if I really wanted an portable electronic map.

I found one for $6600 might be a bit too expensive… :wink:
* H-Star technology for subfoot (30 cm) postprocessed accuracy
* Submeter accuracy in real-time
* Carrier postprocessed, 20 minutes tracking satellites 10 cm, 45 minutes tracking satellites 1 cm

Okay that one came right back at me, I did not lookup the GPSMAP 295 and you did not lookup the Venture HCx: The HCx doesn’t do driving directions, at max it gives you a bleep.

This GPS is primarily an outdoor unit. Rugged and transflective screen (even readable while the sun is shining). Popular with hikers, mountainbikers, geocachers etc. It has support for WAAS/EGNOS but I can’t see the difference to be honest. Under good conditions the unit reports a max error of 3-4 meters, inside the car it reports around 6m usually, which is often enough to determine even on which lane of a highway I drive (inner/outer).

Regarding it’s suitability using as an navigation aid for aircraft, I don’t know.

Hi,

There may be a gap around 1000 euros. Two or three times more and you could have a try with Magellan Mobile Mapper 6, Trimble GeoXT or Topcon GR-3. Or then you could search from precision farming side, for example http://www.trimble.com/agriculture/aggps-252-receiver.aspx?dtID=overview antenna-receiver connected to some rugged PDA, like TDS Recon.

Sure I looked up the Venture HCx. That’s why I said that I appreciated your tip, i.e. I was looking for GPS devices without all the car-driving baggage and the Venture HCx seems to be in that category.

Aviation navigation no longer important for my purchase selection. Nowadays aircraft GPS tends to be firm-installed and coupled to all the other avionics so it’s now in a totally different category from “consumer” GPS.

A postscript to this: I just bought a Gillson active antenna (€25.90 plus postage) and attached it to my existing GPS when using it in the car and had a dramatic improvement in the number of “visible” satellites and the strength of their signals. The EPE drops from 8-15 metres down to a generally consistent 4 metres (except when driving through dense forest). Also, when I drive around the same route several times the recorded tracks coincide much more closely than before.

Of course, it could simply be that because the Gillson is easy to attach to the roof of the car and my previous antenna was inside the car in front of the windscreen the improvement is simply a result of positioning the antenna outside the car. I couldn’t care less. For €25.90 I have what seems to be much higher precision.

Paddy

Ah good point because that’s what I’m basing my experience on, a small very inexpensive USB GPS puck (magnet that attach to the roof). It worked like a charm, the best position was in the middle of the roof. I get abit worse from a GPS on the bike, perhaps that has something to do with the roof blocking some RF noise… Dunno…

All the good antennas seem to be very squarish 30cmx30cm, so it seems you would need some kind of base for the antenna…

This is when you would like to have some one with radio background come by and say something.

For 12 years ago, that was the only choice if needing high accuracy. Today you can construct a kit for $300-$500 that gives 1 CM accuracy, when combined with an Android RTK feed . https://learn.sparkfun.com/tutorials/gps-rtk2-hookup-guide/introduction

And you can also activate the hidden binary recording with old nuvis, and then convert to NMEA format and postprocess them. Not 1cm accuracy, but always below 1m.

Newer smartphones with L1 and L5 bands might fulfill your need to a certain degree. I don’t know if they ever made a handheld gps/ bluetooth receiver logger, haven’t seen one during my search.

Chinese RTK gps seems cheaper and works, for example Hi Target and South brands

The device in question (in the original post) is now 20 years old so I kind of doubt that this thread should be resurfaced.

It was a (now hidden) “say nothing” spam post to point users at a website in the profile.