+lostinjersey Posted January 23, 2003 Share Posted January 23, 2003 I have used a Magellan 330x since I started caching 16 months ago. FOund it reliable and a good overall unit. I wanted turn by turn directions! SO I looked into it and I'd have to pay $1000 for a street pilot III (NO WAY!) or use one of the add-ons to the Palm pilots. Trouble is they cant be used unless you program the route in on your PC. no in the field meddling. No good then. So I broke down and picked up a garmin V Deluxe after running into a geocacher at a cache who had one. I recently went out caching & figured I'd bring both. Well they had me running in circles because they were consistantly 10 degrees apart. They almost never agreed so I'm wondering if anyone else has gone caching with 2 receivers, and what their experience was. Also wondering if theres any way to know which is more accurate of these 2 models. I'm tempted to stick with the new one since i like the interface a lot better. I did a search for this topic & foudn nothing except other threads unrelated to what I wanted to know. www.gpswnj.com Quote Link to comment
+Dave_W6DPS Posted January 23, 2003 Share Posted January 23, 2003 Are you actually carrying two GPSr unit turned on at the same time? If so, try using one to find a location and note the coordinates, turn that one off and turn on the other. See if they are closer this way. Two receivers opperating very near each other, say less than about 2 to 8 feet depending on the receivers, can interact due to their IF stages interacting. Sometimes, I have seen one ham transceiver so desensitized by a common AM/FM radio that it was useless when both were turned on. Other times the effect is much less. If they work okay when one is turned on, but not both, the answer is only to use one at a time. If they give different readings when only one is turned on, something else is going. Take both to a known location and see which is reading correctly. Hope this helps! My two cents worth, refunds available on request. (US funds only) Dave_W6DPS Quote Link to comment
+CWL Posted January 23, 2003 Share Posted January 23, 2003 Well, I've been in groups out hunting caches. (1 Meridian Green, 1 Sportrack Map, 1 Sportrack Pro, and 1 Garmin GPS V) We start off on the same trial but when we got near the cache location we usually started off in different locations. It also usually varied which one of us found it first too. After we all found it we would compare stats. They didn't vary too much. Sometimes one was more accurate than the others but on the next cache it was oppisite. It all depended on what kinda mood our GPSr was in I guess. Quote Link to comment
+lostinjersey Posted January 23, 2003 Author Share Posted January 23, 2003 quote:Originally posted by Dave_W6DPS:Are you actually carrying two GPSr unit turned on at the same time? yes. magellan in left hand, garmin in the right. I think (cant recall for sure) but when I sat them on a rock to reposition while I hunted possible spots, i think eventually they got closer together but they never were closer then 5 degrees. www.gpswnj.com Quote Link to comment
+Olar Posted January 23, 2003 Share Posted January 23, 2003 quote:Originally posted by Gwho:.....they were consistantly 10 degrees apart. Gwho, I experienced the same thing when I upgraded from a Mag315 to the GPS V. It bothered me at first until I checked both units (seperately) at one of those surveyor's geodetic sites that have the coords engraved in a plaque. Both units were very close in accuracy with the difference being less than each units respective error estimate at the time. I no longer cache with them both powered on but do use the 315 as a backup. By the way when you say your two were 10 degrees apart do you actually mean minutes or fraction of minutes? 10 degrees is quite large and would put you in another state. Cheers, Olar "You are only young once but you can stay immature forever" Quote Link to comment
Kerry. Posted January 23, 2003 Share Posted January 23, 2003 10 degrees apart something needs to be clarified with that, 10 degrees what? certainly couldn't be 10 degrees in position , 10 degrees in bearing perhaps ??? Receivers running side by side won't have any affect on each other as far as signal reception etc is concerned. Different makes/models and same models will generally be different for many and varied reasons but the difference will still be within the spec. Cheers, Kerry. I never get lost everybody keeps telling me where to go Quote Link to comment
dboggny Posted January 23, 2003 Share Posted January 23, 2003 quote:or use one of the add-ons to the Palm pilots. Trouble is they cant be used unless you program the route in on your PC. no in the field meddling. not true, you can do routing on your palm pilot with Delorme xmaphandheld addition. no need to do it on the computer first SR and dboggny. Quote Link to comment
peter Posted January 23, 2003 Share Posted January 23, 2003 If the observed discrepancy is in the bearing, is it possible that one receiver is set to 'True North' and the other to 'Magnetic North'? In New Jersey that would lead to a difference of about 13 degrees. Quote Link to comment
+canadazuuk Posted January 23, 2003 Share Posted January 23, 2003 I've been using a Garmin Vista and a Magellan 315 AT THE SAME TIME, and I have to say, the Magellan keeps a better signal in moderate tree cover... Yes, the WAAS is turned off on the Garmin. I'm trying to figure out if I'm going to keep the Garmin or not, and I can't make a strong case for it... I started with the Magellan, and it seems to do just fine, the really big thing for me is signal reception, and I wonder if the Magellan simply has the better antenna?? I love the Vista's extras, but the tracking seems to lack... zuuk Quote Link to comment
+Searching_ut Posted January 24, 2003 Share Posted January 24, 2003 I tend to carry an Etrex Legend and sportrak map on many of my outdoor jaunts, to include my geocaching. Under good reception conditions, Both units seem to be within a few feet of each other on distance to go, and both units seem to tell me to go the same way. As reception gets a little worse, the Sportrak reported position often lags my real position by as little as 50 feet or so to distances as great as a couple hundred feet. This can create havoc with direction guidance unless you're approaching more or less along a straight line. In these conditions I generally navigate strickly with the Legend as it gets me to the cache more quickly and you can navigate with the compass arrow quite easily when compared to my sportrak. On the rare occasions where reception gets really bad, I end up having to stop and let the receivers sort themselves out for a couple of minutes prior to using the positon for anything. In this case I generally use the Sportrak as the averaging seems to help. I get a bearing and distance reading then use a compass to head off again. My basic rule of thumb from experience is that in anything but good reception conditions, use the Legend for guidance while on the move, and the sportrak when stationary. Try to use both and you'll end up confusing yourself. In good reception conditions it doesn't matter what you do as they just seem to work great. For what it's worth Jeff Quote Link to comment
GRANDMASTER CACHE Posted January 24, 2003 Share Posted January 24, 2003 Hi all, Does the regular ST Map not have a bearing indicator? I am familiar (having had) with the Legend's needle-to-bearing indicator, but the ST Pro also has the same feature (instead, the bearing is outside the ring). One does not confuse me more than the other. But if the Map doesn't have that feature, it would be worth getting a unit that does, IMO. As for the side-by-sides, my buddy had a real hard time getting a lock with his GPSV when I had my STPro on. So we decided to experiment. We turned both off. Then, the GPSV on first. Quick lock. The STPro then struggled. Aha! Reverse procedure, and as expected the STPro got a quick lock while the GPSV floundered. When both units came on second, their EPE left a lot to be desired. So, I think there's more than saying two units can be operated side by side with no problem. I think there is indeed a problem, or the birds in the sky were just playing singular games when we did our experimentation. I suggested this experiment because I had read here on numerous occasions where two units operating side by side could indeed throw each other off. I remain steadfastly convinced that they must be able to. I can't imagine solid GPSrs taking turns having a weak stomach, oddly enough when they've been turned on second, respectively. I wouldn't cough up the GPSV, if you like it. We've used those and they work just fine. That autorouting can be nice, if you're into that sort of thing. Great for driving directions, but some devious cache placers can really mess with the "closest to" destinations with those GPSVs. What if the "closest driving destination" (the one it autoroutes you to) takes you to a street which is closest by definition, but there's no access to the cache from said street. Oops. This has happened a few times. It's always nice to take that into consideration when placing a cache. We're collecting the spots around here where autorouters take you to the backside of a hill, but unfortunately the street contains houses with fences you can't go over. It's fun to take the trails up to points like this, especially if ya gotta drive all the way back down a hill and around to an accessible starting point. Hey, all in the hide, eh? Still, that doesn't render the autorouting useless by a long shot. They are awesome when driving from one address to another, in that they autocorrect (quite the necessary feature for dunderheads like myself!) And irregardless, one should always zoom out on the map screen, locate the cache icon, and then get a bearing on the streets and then excercise judgement in "which way" you want to drive to get to a cache. A good example (actually, two of them) are the following: Right Side of The Track (where autorouting took us up a street and real close to the cache - unfortunately, any fence to be hopped was on private property and two vicious dogs prompted us to rethink our launching pad ) The other is a M&J cache. From where we punched in the coords in San Jose we would have to have driven considerably farther (into Saratoga, up HWY 9 and into a fees-due county park) than looking at the "highest detail" setting on the STPro and noticing there was a nice fat trail (Old Sanborn Road, actually) right off Black Road. No cost to park, and I got a closer reading to the cache from the trailhead as opposed to the county park. But the best example (another M&J classic) was a cache placed in Steven's Creek. Egads, tons of parking "close" to the coords, but darn those clover-leaf on/off ramps, eh? They'll get ya every time! I think there's no doubt we'll eventually get an autorouting GPS because they are nice to have for driving directions (but unless it's an address, I'll trust a visual on a map, myself!) Now, I'm off to go think of where to plop these two nice caches labelled, ready and waiting! If you hide it, they will come. Grandmaster Cache Quote Link to comment
+apersson850 Posted January 24, 2003 Share Posted January 24, 2003 quote:Originally posted by Gwho: quote:Originally posted by Dave_W6DPS:Are you actually carrying two GPSr unit turned on at the same time? yes. magellan in left hand, garmin in the right. Wow!Some of my friends (?) consider me a geek, but I have only one GPS... May I quote you to them?? Anders Quote Link to comment
+GOT GPS? Posted January 24, 2003 Share Posted January 24, 2003 I have done a hike a couple times with a MeriPlat, and a GPS V. they both seemed to work. One Idea is to attach an external antenna on GPS units, that have an external antenna connector, and shield the GPS units with Metal, and see if that works. Ive done Geocaches with both GPS units, and they amost go off in opposite directions, when within 100 feet of the cache. 3 experiments: 1) try the experiment with both GPS units within one foot of each other. 2)Put both GPS units several feet apart, and the antennas near each other. 3)Put both GPS units near each other, but the antennas several feet apart. Would item 2 be possible?? ------------------------ My home page about GPS units and information Quote Link to comment
BassoonPilot Posted January 24, 2003 Share Posted January 24, 2003 I keep both of my GPSs plugged in and operating in the car, and when I accompany my daughter on cache hunts, we carry both. The two GPSs rarely disagree by more than 50 feet, and are usually in close agreement. Quote Link to comment
Kerry. Posted January 24, 2003 Share Posted January 24, 2003 quote:Originally posted by GOT GPS?:.... Ive done Geocaches with both GPS units, and they amost go off in opposite directions, when within 100 feet of the cache. _3 experiments:_ 1) try the experiment with both GPS units within one foot of each other. 2)Put both GPS units several feet apart, and the antennas near each other. 3)Put both GPS units near each other, but the antennas several feet apart. Would item 2 be possible?? All 3 possible (including #2) plus a few other variations to the theme. However have never seen any indication (recorded or otherwise) that 2 antenna's, 2 GPSr's or any other combinations of makes/models of any affect on accuracy or operation. The main thing with running 2 antenna's (especially large aspect antenna) close together is any masking issues as that will show differences (artificial ones that really don't exist anyway). everybody keeps telling me where to go Quote Link to comment
+lostinjersey Posted January 25, 2003 Author Share Posted January 25, 2003 quote:Originally posted by Anders: quote:Originally posted by Gwho: quote:Originally posted by Dave_W6DPS:Are you actually carrying two GPSr unit turned on at the same time? yes. magellan in left hand, garmin in the right. Wow!Some of my friends (?) consider me a geek, but I have only one GPS... May I quote you to them?? Anders Want pictures to go witht hat? [] www.gpswnj.com Quote Link to comment
+lostinjersey Posted January 25, 2003 Author Share Posted January 25, 2003 quote:Originally posted by Olar:By the way when you say your two were 10 degrees apart do you actually mean minutes or fraction of minutes? 10 degrees is quite large and would put you in another state. yeah I get your point. I meant fractions. i.e 41 10.120 vs 41 10.110. thats the difference I was refering to. sorry for the confusion www.gpswnj.com Quote Link to comment
+Alan2 Posted January 25, 2003 Share Posted January 25, 2003 That's a difference of about 60 feet I believe. Alan Quote Link to comment
+Alan2 Posted January 25, 2003 Share Posted January 25, 2003 Were the longitudes equal? alan Quote Link to comment
+lostinjersey Posted January 26, 2003 Author Share Posted January 26, 2003 ...sometimes by as much as 10-15 as well.... when I sat them on a rock and went off to hunt when I came back they sometimes were much closer. sometimes. www.gpswnj.com Quote Link to comment
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