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Links to information about how to monitor the weather

The following URLs have been culled from posts to a mailinglist about monitoring weather with Dallas 1-wire, MicroLan, iButton devices. (Those are all related trademarks, all included for the delectation of search engines. Dallas is also related to Maxim and Dalsemi. Brand identity crisis? Them?)

This is a rough and ready page, in the wrong place, with the wrong name, but it may link you to what you want!

Entries saying things like "This site has..." should really say "I have heard that this site has..." My efforts will be worth at least what you've paid for them. (smile).

Apologies to authors for stipping out much of the identifying material, and (I hope) all emails. I thought listing one that shouldn't have been listed worse than the converse? If you want to know more about things you read here, have a look in the Dallas / Maxim Semiconductor weather mailing list archives. Sadly, the discussion group is no more. Click here for information on it and alternatives.
I have checked all the URLs, but of course the contents of the pages are subject to change. Don't hesitate to alert me to problems?

Apologies if you think this is too rough to be inflicted on you... use the search button (above) to save hard work? I will try to tidy this up one day....
Just before we begin the main work of this page, I am going to give you some links to my not-scruffy work on the joys of computerized weather monitoring...

An entry point to a bunch of pages I have written on the subject.

Some pages about the Dallas Semiconductor 1-Wire chips and MicroLans... which have many uses, among them weather monitoring.

A subsection of the first site, addressing using the Dallas Semiconductor 1-Wire product line / MicroLans.

Q: Can anyone offer components/circuits on building a pulse counter to collect kilowatt information directly from a utility electric meter? I would use the DS2423 counter but I can't find any help on the internet about designing the magnetic pulse detection side of this type of device.
(Asked: Subject: Re: [weather] Electric Meter Pulse Counter
Date: Tue, 9 Oct 2001 20:45:18 EDT)

A: (Question may be based on some misunderstanding.) Take a look at:

Electric meter reader

The above gave rise to discussion of reading flow meters on water lines. Which gave rise to...

A: Look at the FT-100 from Gems Sensors:
Link WAS: http://www.gemssensors.com/PDF/Catalog/FT-110_J8.pdf

I'm intending to use the unit that runs up to about 5 gpm (my well pump can only manage 6 gpm). It has a nice pulse output, and costs $70.

Someone else wrote: I came across a Seametrics flow meter with totalizer. It uses a current-loop so I don't think the interface would be that difficult. (no, I don't have the URL. Use Google or similar.)

Subject: Re: [weather] New Wind Chill Formula
Date: Tue, 23 Oct 2001 12:33:56 -0500

Ray Dzek wrote: I found an interesting article in the local paper regarding wind chill today. Aparently, a new method of calculating wind chill is being adopted starting Nov. 1, 2001

Windchill info from ggweather

The formulas are posted under each of the charts at the bottom of the page.

(Ray Dzek's site)

Subject: Re: [weather] Humidity Sensor
Date: Wed, 24 Oct 2001 10:58:36 EDT

Someone asked: Has anyone done anything with the boards from......
Fascinating Electronics

They have...

Wind direction (by pot) $50
Wind speed $50
Rain tipper $40
Temperature and humidity unit $25

The tture / humidity unit's technical info was thin. I think it converts humidity to a square wave, with frequency proportional to humidity.

Subject: Re: [weather] pressure to altitude corrected with temperature Date: Mon, 19 Nov 2001 10:56:16 -0700 (MST)

There was once a good page with formulas for air density, pressure, etc. inside the USAToday site. It may still be there, but the deep link I had for it is reported as "forbidden" now. The link was...http://www.usatoday.com/weather/wbarocx.htm, USA Today weather formulae.

The NOAA mesonet map web page was recently upgraded and has lots of surface weather data that are publically available. The URL is,

NOAA Mesonet

Users can get the METAR pressure readings here to check barometer measurements. However, the real advantage is that you can send in your surface weather data and have it posted on this map and compare your measurements with nearby stations. Many regular contributors to the Dallas Semiconductor Weather list are also regular contributors of data that appear on the mesonet map.

The mesonet data are used by our lab in numerical weather prediction models. The data are also sent to the National Center for Atmospheric Research and to the National Centers for Environmental Prediction. And the data are made available to the National Weather Service Forecast Offices.

Information on how to join and start sending in your data is at


Both Arne's and Brian's weather programs have the capability for you to send data through the internet using dial-up or a full-time connection.

Subject: Re: [weather] Ordering Items
Date: Wed, 5 Dec 2001 07:49:59 -0800 (PST)

Someone said: I would like to order 8-10 temp sensors and 4 or 5 humidity sensors, I can't seem to find anyone that sells them and I don't see them on the Dallas Site online.....

Someone suggested trying:

Allied Electronics

DS18B20 programmable temperature sensor Allied Number 671-2026 (You can check for the others, they carry a number of one-wire parts).. and...


HIH-3610-001 Humidity sensor. Note that this is the element, you'd need to purchase the remainder of the onewire parts, or do like I did, and covert the thing to PIC :)

(Another bit of information about Newark: Someone I (TKB) trust to be sensible, reasonable placed a $1000 plus order with them. There was some snafu. Newark required him to place the order again, extend the load on his credit card a furthre $1000+, in circumstances which seemed unreasonable, from the stories I heard. I wrote Newark for their side of the story, but received no answer.) ----
Another poster's views....

Maxim/Dallas is the best source (cheaper) on Dallas parts. I order in quatities of 20 or so. it almost always takes a couple of weeks. The DS9097 took a month and a half.

Newark has most of the parts needed for most projects, they are considerably higher in price. But if you need one or two in a hurry that is the best bet. I have had problems ordering online from Newark, their shopping cart is broke and will require you to order like 200 or so of each. Talk to a person on the phone and I have been able to order in small quantities.

Mouser is the best for parts except for sensors and Dallas parts.

For the humidity sensor, HIH-3610, the best source I have found is onlinecomponents:


I will continue to try to stock a few barometer, humidity, and LD boards. I order them 10 at a time, about the only way that makes economic sense.

The GDM-450A is a good multimeter (4 1/2 digits) at not too high a price for those of you building barometers.

Subject: Re: [weather] Snow Measurement
Date: Wed, 5 Dec 2001 12:36:31 EST

The mailing list contributors have outdone themselves, several times, in discussing measuring snowfall. Some of the gems....

This elementry school had an interesting Laser Snow Sensor, unfortunately the, the site seems to have been removed from the web. It was at Glenshire, a sub folder from....

Placercoe K12 CA, US

Subject: [weather] Snow measurement Date: Fri, 27 Sep 2002 12:10:02 -0700 If you want to do it right... A NOAA page posted at a University of Wyoming site (Ever been to Wyoming in January? I bet they know a bit about snow!)

More on snowfall...

I keep my rain gauge in a well insulated box during the winter with a few light bulbs. It does a pretty good job of melting the snow so that the gauge can count the tips.

There was a project on the list some time ago that showed a rain gauge heater.


There is a table to give a rough estimate of snowfall by temperature.


Someone else commented:"Hmmm ... that's interesting ... I read another official looking page that said it needs to be measured as precipitation as in the water form. I guess I should eat my words, er snow, now :)"

Jim Jennings wrote: Here's another one with possibilities. They have some software examples also. I am not sure how effective snow is as an ultra sound reflector, though....

Acroname Robotics

American Science & Surplus used to have Polaroid cameras with ultrasonic range finders on them available but I don't see anything like that on their site right now.

Other possible sources of parts, inspiration...


For Polaroid Sonar Ranging Primer:


Robotoz... Look part way down the page for: Specifications, Series 6500 Module (PDF Format - 172Kb), Sonar Ranging Primer (PDF format - 224Kb)

Arizona Microchip offers info. Search for "Ultrasonic ranging". Application Note AN597 contains info on how to do it.

Regarding the Acroname device: The Devantech srf02 range finder $25) was covered in an article in N&V that should be coming out in a few issues. (Note written c.12/01) It may work as a range tester for snow, however I don't have any snow this year and can't test it for people :( darn and I like snow too. Maybe somebody who owns one of these sensors could try it out in snow.

There's a sensor made by "Campbell Scientific" It uses ultrasonic beam to measure distance. Interesting is that the output is a series of pulses to give measurements in mm. Could not find a price on the web site.....try: Campbell Scientific

Re- the Campbell sensor: I think that would be of more value to mountain-dwellers for measuring snow-pack or base, as the accuracy is quoted as "+/- 1 cm or 0.4% of measuring distance, whichever is greatest."

Subject: [weather] neat link (potentially)
Date: Wed, 12 Dec 2001 12:12:49 -0600

I picked up this software link on an email. Here's the blurb, snipped. Sounds too good to be true... I HAVEN'T CHECKED THIS OUT. Spyware?


Searching for something more comprehensive than Weather.com? This program offers weather information from all over the globe--literally. Examine real-time weather conditions, as well as earthquake and volcano information, using live Webcam images, weather-monitoring systems, and satellite images. You can rotate the globe in any direction, get close-up views of geographic regions, or zoom out to view the entire Earth from space. The night-time shadow is mapped across the globe showing daily and seasonal changes, and clouds covering the earth are downloaded from satellite images on an hourly basis. Five-day weather forecasts and current conditions are available in over 800 cities worldwide. You can also use this application as a screen saver.

Version: 1.3.7
File Size: 1445 KB
Price: Demo
Operating System(s): Windows 9.x, Windows 2000, Windows NT, Windows 95, Windows 98

EarthBrowser could at one point be downloaded from PCWorld, and may still be on their site, but the deep link I had no longer works.

Subject: Re: [weather] neat link (potentially)
Date: Wed, 12 Dec 2001 22:53:28 -0600

Some/most of you are monitoring your weather stations/sensors and some of you are sharing that info via uploading it to various servers. Here's another you might not be aware of, and they post it on their site for free (with your credits, etc, too!).

Weather Underground offers free uploading of your personal weather station data and they offer it to the public via their website. Here's more info on the PWS

And, just a quick plug: My Weather1 software can display your weather conditions as well, including your other favorite travel locations, weather cams, satellite images, radar, weather warnings, etc, etc. It also includes a charting tool, so you can chart temperature and/or humidity trends. Tons of stuff.

Subject: [weather] Re: Different types of sensors...
Date: Mon, 01 Jul 2002 11:28:07 -0600

Here are a couple of sensor vendors I have been looking at. I don't recall seeing any specific 1wire circuits for these already done but most can just use the battery monitor's a/d and a few just need a pulse counter. There was an article about an ammonia sensor in a recent issue of Sensors magazine

pH should just need a probe and the battery monitor circuit. Try Omega and Markson for probes.

I couldn't get through to www.markson.com when I tried (Jan 03).

Both of these also have several specific ion probes that can be used just like pH probes. These include disoovled oxygen, nitrate/nitrite, etc... Conductivity for TDS can be done the same way.

Figaro does gas sensors.

Subject: [weather] Aurora Detectors
Date: Sun, 21 Jul 2002 10:53:13 +0100

For those who are trying to extend their systems - has anyone done any work ondetecting geomagnetic storms? As they indicate possible aurora activity, it might be interesting.

I subscribe to the

Aurora Watch

e-mail notifying service. They also had two detector designs.

I guess you could do something with linear hall effect sensors (say three at mutual right angles). It's on my 'sometime' list, but if it's been done I'd be interested in the result

The May 2001 issue of Poptronics has an article on building one of these as well. Page 29 FLUXGATE MAGNETOMETER

More Aurora: Be sure to follow the links to Fat Quarters Software, which apparently was once at www.thunting.com/geotech/mag/fmx1.html, but I got "Temporarily closed" when I looked Jan 03.

More Aurora: This tiny board could be connected to 1-Wire directly using the 2438 and parasitic power (strong pull up during measurement). Also not too expensive (abt $80) Stefan Mayer

Something (edited) I found with Groups.Google.Com....
Subject: Re: [weather] Aurora Detectors
Date: Wed, 24 Jul 2002 11:38:41 -0500

If you're interested in Aurora, you might want to check out this very interesting radio astronomy equipment also ...


The "Radio Astronomy Teachers' Notebook" from this guy (Jim Sky) was also interesting. (To the poster) It talks about ways to measure solar flares, jupiter storms, detecting meteors, and has a bunch of notes on constructing radio telesscopes, including antennas, amplifiers, etc.

Eventually {the poster} wants to try detecting those jupiter storms. This place sells a jupiter radio telescope tuned for listening to the storms on jupiter (listed in above link, more info here)


Here are some jupiter prediction tables


The schematics for Dick Flagg's JOVE jupiter receiver are probably available on the web somewhere.

One other note re aurora: {the poster} lived in CA for 5 years and there is no visible aurora there. There is also basically no lightning. {he} had the Dallas weather station set up there and had no interest in lightning detection because {he} saw lighting exactly once in the five years that {he} lived here. Now {he's} back in the 'great white north' and suddenly both lightning and aurora are interesting again. There are some really spectacular shows of aurora up here, sometimes it covers almost the entire sky.... END OF QUOTE FROM POST.

Here's a very precise magnetometer. However, I'd agree that the 1-Wire net is not suited to data acquisition at the high rates needed. It could signal when a threshold is crossed as detected by another processor on the network. Very Precise Magnetometer (xxx.lanl.gov/html/physics/0207062)

That magnetometer design using a silk thread reminded me of a humidity sensor I was reading about yesterday. Is uses ... hair! The hair hygrometer takes advantage of the fact that hair changes length with humidity. Twisted hair generates torsion.


Apparently blonde hair works better. Guess they do have more fun.

Another thing I read yesterday that was very interesting was this introduction to LIDAR.


I noticed that there are tons of lasers and also photomultipliers available on ebay.

I was looking at various ceilometers, and I just might try building this one. Not quite a ceilometer but pretty cool.


A further note arising from the aurora discussion:
Subject: Re: [weather] Aurora Detectors

Date: Wed, 24 Jul 2002 23:14:10 -0700

{The poster} was stationed at Fort Richardson at Anchorage, Alaska in 1966-'67 and {he} saw the most awesome aurora display that winter that words fail me to describe it. It looked like a curtain, complete with folds, and had the most vivid colors in bands top to bottom. It stretched from horizon to horizon. {He} swear {he} heard a buzzing sound in my head while it was at its most intense.

Subject: [weather] Air Monitoring QA Manual

Date: Mon, 22 Jul 2002 14:54:02 -0500

Here's some info from the California Air Resources Board "Air Monitoring Quality Assurance Manual". If any of the links give you trouble, go to www.arb.co.gov, and seach from their homepage.

A 6kb pdf is available...

... and once upon a time, you could download things like....

Siting Requirements for Meteorological Equipment
Meteorological Parameter Procedures for Inside/Outside Temperature Sensors
Meteorological Parameter Procedures for Wind Speed Sensors
Meterological Parameter Procedure for Wind Direction Sensors
Meteorological Parameters Percent Relative Humidity Sensors
Meteorological Parameters for Met One 090D Barometric Sensor
.... but I don't have links that still work for those. Dig!

Subject: Re: [weather] New weather device
Date: Fri, 13 Dec 2002 09:17:00 -0800

Has anyone seen the Weather Duck? Seems like an all-in-one for indoor climate sensing. Neat thing is that it has a 1-wire port for adding more sensors. Drivers are Windows-only, but I can't see why it wouldn't be usable from Linux. Has a webcam add-on, too. We're planning on getting some for our computer rooms, but it might be useful at home, too.


Price WAS pretty good: $119 (when you include their $20 shipping charge), but was due to rise dramatically in Feb 03.

I just wish they had made it *look* like a duck - along the lines of those mallard telephones :-) Would be very amusing!!

The WeatherDuck is really nifty! It contains the same basic firmware as The LINK does and emulates a DS9097U. It also supports all the ASCII Link commands as well as a whole set of commands for getting temp, RH, light, and three analog or binary inputs. It has a nifty air-flow sensor, too.

It is intended to plug into the serial port on the back of rack-mounted computers and monitor the conditions inside the rack.

Yes. The WeatherDuck works fine on the iButton viewer as far as I know. You could use it as an interface and also add more sensors.

I'm interested more in the total room conditions than just a single rack. Most likely I'll snake some serial cable around to some ladder racks in the middle of the room. Not a big room to begin with, but we had our paging sensor go out and we were never warned when the room hit 99F. You can never have too much redundancy.

However, if it emulates a DS9097U, I wonder if it can be scanned with the ibutton viewer and read from other 1-wire software. That would eliminate having to write any new software for it. Anyone going to tear their WeatherDuck apart to see what 1-wire chips are inside? =)

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