thermometer

REI zipper pulls, they work pretty good.

Before a fall camping trip I got a cheap min-max thermometer from Wal-Mart to establish limits of a quilt I have mixed feelings for. The thermometer brand is Accurite. It weighs 34 grams (1.2 oz) and has a hole for a caribiner or lanyard. I am sure it cost no more than $7. What I have read in past posts is that the zipper-pull thermometers are unreliable, and my own experiences agree with that analysis.

If you are OK with a good approximation a zipper pull thermometer is cheap, small, light and unobtrusive.

The min max feature mentioned above sounds nice, but 1.2 ounces is a lot for those of us who are gear weight obsessed and don't really consider the thermometer a necessity.

On bike tours, I got used to my bike computer speedometer having a decent thermometer. It worked surprisingly well (even in the sun if moving). It does make me want to carry one, but I thus far have not found one other than a zipper pull one that I am willing to carry.

I have to wonder how well the watch ones work. Since I mostly want to know the temperature first thing in the morning, and take my watch off at night, body heat shouldn't be a problem.

I'm also interested in monitoring temperature (and humidity) to determine at which temps and conditions my system works, but figured that it would be neat to also be able to log the temperature as a function of time throughout the duration of the entire trip. My Suunto vector watch used to do this, but after 12 of nearly continual daily use, my old Vector watch isn't doing so well… still works, but some of the buttons seem to get stuck.

I did some googling, and there is a product out there called iButtons, they are tiny "therocrons", mainly for logging temperature for scientific purposes, they seem very robust, waterproof, tiny and weigh about 3 grams!

The cheapest one I can find is: http://www.embeddeddatasystems.com/DS1920-F5–iButton-Thermometer_p_94.html but then you also need a USB or ethernet adapter: http://www.embeddeddatasystems.com/DS9490R–USB-to-1-Wire-iButton-Adapter_p_131.html

and there are many iButton models, depending on temperature range and sensitivity, and they also have ones that monitor humidity.

At about $35 after the dust settles, for a device with a non-rechargeable non-replaceable battery (though, it apparently lasts many years), just to log temperature for the trip is a bit steep. I think it'd be neat to know the temperature and humidity as a function of time on a trip though, especially for those interested in rigorous gear tests or review sites.

I'd love to find something cheaper, as I think it'd be neat to see the temperature continually over a trip.

There was a good discussion of the iButtons here

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=39246

I have searched hard for a max/min that is small and light, harder to find than one would think. You can get lots of thermometers but not ones that record the max or min partly because they have to be on all the time so battery life is an issue. the iButtons are good if you don't want to know in the field what the temp is (you down load the info at home). If you want to read the temp in the field the lightest I have found just for temp (no max/min) is an Extech 39240 at .9 oz., waterproof and fast reading and will record the max/min but for only when it was on.

The smallest and lightest recording max/min I have found is this one

http://www.amazon.com/Digital-Thermometer-Hygrometer-Temperature-Humidity/dp/B00153KVYG/ref=sr_1_16?s=industrial&ie=UTF8&qid=1360677032&sr=1-16&keywords=digital+thermometer

for cigar humidors or wine cellars so not waterproof and only goes down to 14 degrees but it has been very sturdy and I just slip it in a small ziplock to waterproof it. Very accurate and the LR 44 battery lasted at least 6 months being continuously on. Also .9 oz when you take the magnet off the back.

Jim,

Thanks for your post…I too wanted something that would record the low temperature at night (I don't really care about the high) to evaluate my sleep system. I ended up with an Oregon Scientific model that weighs almost 3 ounces and isn't weatherproof! I also paid $29-$39 for the stupid thing. And you have to push the right combination of buttons to see the minimum temperature and remember to reset it.

I'm running out today and picking up one of these! At $5.96 it can't be beat!

Note that the "cheapest one" that Rob found is not a data logging ibutton … it provides instantaneous readings and needs to be connected via a "1-wire network" to a device that can read and display or record the reading.

Many many options, took me several minutes of careful reading to sort that out.

The lowest cost logging ibutton on the site he found seems to come in at $22 for the ibutton itself plus about $28 for the USB adapter.

That said, ibuttons are very useful and widely used by climate/weather data geeks. I doubt you can find equivalent function at lower cost.

Ah, sorry about that, I thought that one logged the data, it seems that there are a few dozen different permutations of the iButtons and I didn't fully read the datasheets. Thanks for clearing that up.

So it looks like somewhere around $50 is the price to get started with the iButtons then… tempting, but a bit much. Seeing Rogers plots in that other thread sure look great though.

I have my $6 AcuRite thermometer from Wal-Mart and it's even better than I could have hoped. The instructions explain that it records the high and the low for a 24-hour period. That 24-hour period starts when you turn it on. The CR-2032 battery slides in and out easily. All I have to do is to put the battery in sometime in the afternoon and let it go. I'll then have most of the day to remember to look at the low temperature from overnight. Brilliant!

And mine, on my scale, weighed only 34 grams (1.2 ounces) including the battery.

hmmm. is this it?

http://www.walmart.com/ip/Accurite-Thermometer-with-Suction-Cup/16888909

That is indeed it. I pulled off the suction cup and it now has a hole that's perfect for a mini-biner.

The other thing I did was to keep the little plastic strip that keeps the battery from being activated. It was easy to wrap around the battery "compartment" and slide it back into place.

If you've already lost your little strip, the peel-off backing from a P-Touch label would work well.

I'm almost embarrassed with how happy I am with this $6 purchase. When your gear is pretty well dialed in and you can knock off 1.6 ounces for $6 I guess it's reason to celebrate. There's not even any cuben fiber involved!!!

i just picked up one in HI-VIS RED on ebay for 8.75 shipped. they had 4 colors available (black i think would be a poor choice as it would probably effect temp). I'm scared of wal-mart.

You can order direct from AcuRite for $7.99 plus S&H:

http://www.acurite.com/weather/thermometers/digital-window-thermometer-00315-00316-00317-00318.html

The “Unpredictable Weather Guys” video on that page is funny.

If you can’t decide how to dress for the day, check out the AcuRite “What To Wear Digital Thermometer”:

http://www.acurite.com/weather/thermometers/6-what-to-wear-digital-thermometer-00536.html

With the remote sensor, you can decide before you leave your sleeping-bag-quilt-tent-tarp-bivy-igloo-pile-of-leaves :-)

Interesting:

Due to federal restrictions, this item cannot be returned by air mail. Customers in Hawaii, Alaska, Puerto Rico and other overseas locations can return this item to a Walmart store.

Guess I'm SOL. I'm guessing it is the lithium battery that is the problem.

I have to object to the "overseas" designation. I know we look like the 6th Hawaiian Island on most maps, down in the lower left corner, but we're actually connected to North America by a large, friendly country that loves hockey, has a queen on their money, and keeps French people as pets.

If you just want to record the min and max, check out the "Coghlan's Time/Temp Digital Dangler":

http://www.amazon.com/Coghlans-Time-Temp-Digital-Dangler/dp/B000S5VRMM

Mine weighs 0.95 oz without the lanyard and seems to work fine. Tiny too. And the battery has lasted almost a year so far.

i've had bally ho good times with my radio shack digital t-meter. it has a remote lead that lets me find out interesting stuff like "how cold is it inside my boot when my foot goes numb ? " (52°). and "how much difference is there between inside and outside an almost all netting tent ?" (upwards of 6°).
i think having a remote sensor is half the hoot of playing with one.
in terms of research , you just gott'a get a remote lead unit so you can compare two places at once.

cheers,
v.

It's always smart to check the functional temperature range for digital thermometers to see if they are suitable for your climate.

The Accutite is good from -4F to +158F … probably desirable for deserts at not too high an altitude but not so much for my locale (far northern midwest US).

The Coghlan's is good from +14F to +112F … near useless to me.

The Mini Digital Thermometer Hygrometer Temperature Humidity Gauge is +14F to +140F … fine for it's intended purpose (humidors) but cold weather camping?

Ibutton thermochrons come in many models but there are a couple that cover -40F to +185F … very adequate except for the highest latitudes or altitudes but require other electronics if you want to know the temp tight now.

Most analog max-min thermometers cover the range of -40F to +120F … some are good to -60F. But bulk and weight and fragility are negatives.

I have a Brunton ADC Wind which has a thermometer and wind gauge

The problem with the thermometer, is the sensor is buried somewhere in the case so it takes maybe 30 minutes to stabilize. So, if the temperature is changing, it can read several degrees off.

Better to have a remote sensor or a probe thermometer like for cooking.

I've taken a cooking thermometer a couple times that weighs 1.3 oz that has a probe. That works pretty good. Don't tell wife.

Jerry,

Could the probe thermometer double as a fever thermometer?

Daryl

>"Could the probe thermometer double as a fever thermometer?

Easy enough to check at home. Take your temperature throughout the day with your probe thermometer. If is it within a range of 1.5F, that's great – your body varies that much during the day when healthy. Note what the average is. It might not be 98.6F=37C due to inaccuracies. But if it is repeatable, make a note of its reading of body temp on it in Sharpie.

I notice individual units of cheap thermometers read many different temps in the store. I pick one that is closest to accurate, say, 69F. Then I check it at home against some known temperate – 32F/0C being very easy to accurately create.

Fever thermometers display the text "lo" if the temperature is less than 90 F or something

They would be okay during the summer : )

one more to look at

http://www.tiptemp.com/products/21941/traceable-pocket-thermometer

Thermometer

I bought and modified the Walmart Accurite thermometer that has been discussed here. See photo and link above. Thanks for the tips.

I removed the outer plastic housing and the thermometer now weighs about .6 ounces. About half of its weight was in that outer plastic walnut shell like housing that was not essential to the thermometer functioning.

CAUTION-The outer housing is made of very brittle plastic. Shards go everywhere when it is broken. Protect your eyes and any other vulnerable parts you might have.

The battery tray clicked into the outer housing so the tray on my now lighter thermometer must be held in place with a piece of tape. No big deal. The thermometer must be inside a zip lock back anyway (with or without housing) if it is used in a moist setting.

Daryl,

Good call. I just picked mine up at Wal-Mart the other day and planned on using the thermometer in the exact same way minus the piece of tape.

I think what I'll do is just keep it in a small zip lock indefinitely. Only shame is that the battery doesn't "click" without the housing and there's no simple on/off button. Besides that it's perfect.