AltitudinalElevationation
Nov. 8th, 2019 03:32 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
ceagleOne of the lil' fun things I really like is having an altimeter gauge in the car with the rest of the gauges, mainly so I can track the subtle climbs and descents that I might not feel in the accelerator pedal, and thus I can make adjustments in pedal pressure to try for the best mileage (during times when traffic is mild of course). It also answers questions as to why the coolant temperature might be slightly higher or lower at a given time.
I've tried just a few, and have had mostly satisfactory results with both GPS and pressure standard types. I also am cognizant of cost and have kept the limits in a sensible lower range of budget. :> As much as I dig analog stuff, in this case I prefer digital due to the potential difficulty of seeing the analog changes while driving. I also tried an inclinometer briefly, but that is too affected by acceleration.
The ones that measure based on atmospheric pressure are fairly standard and must be calibrated, plus one needs to take into account the more extreme variations of weather that may affect them, even if it's not all that worrisome.
The pressure one of choice is the Celestron TrekGuide. At $30 it was a steal, and is amazingly accurate and easy to read.
The GPS one I've used the most is my Magellan car GPS unit. At $105 it is also the only one of the standalone GPS units that has the elevation feature, which uses satellite triangulation, so it's not affected by weather, but it does need minor calibrations once in while. Where the pressure based unit can be off 20 to 100 feet (not dreadful), the GPS unit doesn't seem to err more than about 10 to 20 feet.
The Celestron is much more portable, with long lasting CR2302 batteries. The Magellan takes a charge when plugged into the car socket, but it doesn't hold it for more than 15 minutes or so (since it's not really meant for out-of-car usage, but it sure would be nice).
Of note, the most fun readings I've ever gotten were when I took these traveling on airplanes. They both gave useful information, but in different ways.
The GPS based one showed the *actual* altitude in flight, whereas the pressure-based one showed the cabin-pressure-simulated altitude :D (which was about 7,500 when I tested it). I've read that the international standard is 8,000 or below so that's right there in the ballpark.
Good measurements to you all!
I've tried just a few, and have had mostly satisfactory results with both GPS and pressure standard types. I also am cognizant of cost and have kept the limits in a sensible lower range of budget. :> As much as I dig analog stuff, in this case I prefer digital due to the potential difficulty of seeing the analog changes while driving. I also tried an inclinometer briefly, but that is too affected by acceleration.
The ones that measure based on atmospheric pressure are fairly standard and must be calibrated, plus one needs to take into account the more extreme variations of weather that may affect them, even if it's not all that worrisome.
The pressure one of choice is the Celestron TrekGuide. At $30 it was a steal, and is amazingly accurate and easy to read.
The GPS one I've used the most is my Magellan car GPS unit. At $105 it is also the only one of the standalone GPS units that has the elevation feature, which uses satellite triangulation, so it's not affected by weather, but it does need minor calibrations once in while. Where the pressure based unit can be off 20 to 100 feet (not dreadful), the GPS unit doesn't seem to err more than about 10 to 20 feet.
The Celestron is much more portable, with long lasting CR2302 batteries. The Magellan takes a charge when plugged into the car socket, but it doesn't hold it for more than 15 minutes or so (since it's not really meant for out-of-car usage, but it sure would be nice).
Of note, the most fun readings I've ever gotten were when I took these traveling on airplanes. They both gave useful information, but in different ways.
The GPS based one showed the *actual* altitude in flight, whereas the pressure-based one showed the cabin-pressure-simulated altitude :D (which was about 7,500 when I tested it). I've read that the international standard is 8,000 or below so that's right there in the ballpark.
Good measurements to you all!
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no subject
Date: 2019-11-08 12:56 pm (UTC)no subject
Date: 2019-11-11 06:50 am (UTC)no subject
Date: 2019-11-08 01:52 pm (UTC)no subject
Date: 2019-11-11 06:52 am (UTC)I also bought an "Alta" watch at one point while investigating these, but it's too tiny to be very useful...
no subject
Date: 2019-11-08 02:26 pm (UTC)no subject
Date: 2019-11-11 06:57 am (UTC)Satellite technology can be a hoot!
I think took them on board after 9 / 11 but I know whatcha mean, ... I've wondered if any one of them might arouse unfounded suspicion... so far so good, though I've only done it 3 times in like 20 years :>
no subject
Date: 2019-11-10 11:35 pm (UTC)Good call on the TrekGuide though; maybe I will look into this as I also have need for a compass pretty frequently and I'm not sure I trust the accuracy of the one in my phone, no matter how many apps there are for this.
no subject
Date: 2019-11-11 07:04 am (UTC)I have been running the TrekGuide one all week, after having found it during my Spring Cleaning project in Autumn :D ... Biggest test was yesterday in fact... down 800 feet and back home ... accuracy was 20 feet, and maybe even less when accounting for the weather change over the 5 hour duration.
If ya do go for the Celestron, might need to look on eBay as I think they might have been discontinued... should still be plenty around new in the case though... :}
I found many during my hunt a few weeks ago, and then got lucky with finding this old one on hand while organizing.. this one was bought a few years ago at Big 5 Sporting Goods.
no subject
Date: 2019-11-11 05:37 pm (UTC)Yeah, I noticed there's a couple on ebay. I guess I should also see if there might even be something more accurate in recent years.
"Encoding" just means that it "encodes" the altitude into binary or whatever format, so that it can be transmitted inside the cockpit over to an aircraft transponder... so when the plane flies in controlled airspace, and air traffic radar pings them, it will send back a note about locally-measured altitude. Pretty neat idea. :)
no subject
Date: 2019-11-12 06:59 am (UTC)So yep if ya want something that transmits or saves the data, you'd need to look for some other models yep yup. The two faves I reviewed are just for car travel live-info mainly. ^v^
And I think you'll find that a 20 ft deviation is pretty good in this field of measurement, especially when based on air pressure that fluctuates.
You might be more in the market for the GPS type, and with additional features if ya really want encoding etc.... and Ive read and seen that even these fluctuate a little... I've recalibrated my GPS one a few times when I get to the beach :>
...or keep that as an option for later and try one or both of these as cheap kickaround versions....
no subject
Date: 2019-11-12 11:41 am (UTC)no subject
Date: 2019-11-30 06:44 am (UTC)*d'oh!* :D