Peet Brothers Ultimeter 2100 Weather Station

© Brooke Clarke 2010 - 2012


                2100 Weather Station Control & Labels
Keypress Sequences
(1) Temp, (2) Indoor = indoor temp at control box
(1) Humidity, (2) Indoor = indoor humidity only if the optional sensor is connected.
(1) (any data key), (2)Up = high value for the day and time it occured
(1) (any data key), (2)Dn = low value for the day and time it occured
(1) Rain, (2)Up = yesterday's rain
(1) Rain, (2)UP, (3)Up = rain this year  [use Down for the lows]
(1) (any data key), (2)Up = yesterday's high
(1) (any data key), (2)Up, (3)Up = highest ever value & when it happened
While the long term value is being displayed it can be reset to 0 by hollding Clear+Date.
Dual Keypress
Baro + Time = 3 hour change in barometric pressure
Clear + Alarm = to turn of flashing battery if a new battery has been installed

Serial Port Commands
Wind + Clear (3 seconds down) = Data Logging Mode
Wind&Temp + Clear (3 seconds) = Packet Mode
Rain + Clear (3 seconds) = Complete Record Mode
Temp + Clear (3 seconds) = Modem Mode

Old (small) Wind Speed & Direction +
 Rain tiping bucket
                  Brothers Ultimeter 2100 Weather Station Wind
Outdoor Temp & Humidity with some weather protection on North side of house.
                2100 Weather Station Outdoor Temperature and Humidity

    Bad Rain Gauge


I've wanted a weather station for some time and this one showed up on eBay for a huge discount compared to the current version and with the tipping bucket rain guage and the outdoor humidity and temperature sensor.  This older version 2100 has a smaller wind vane and some other differences.

Feb 2012 Update

The Virtual Weather Station software ran out of memory and I don't see how to avoid that.  In the setup there's a fixed number of observations available for storage.  By making the time between observations long you might be able to go for awhile, but at some point it stops.  I don't see why they did that.  A modern hard should be able to last for years.

I see why they offered the Pro anemometer.  There's strong gusts of wind outside but the wind speed is showing zero.  The old version small cups just can't overcome the friction and get started.
The cost to change it includes the Peet fee for the upgrade plus hiring roofers (hundreds of dollars) to take down the mast and reinstall it, so not something that's going to happen anytime soon.  Note my control box shows CAL when the top row left and right buttons are pressed, so needs to be replaced in order to use the Pro anemometer ($299 - $70 trade in = $230).

A number of times the main LAN cable has unplugged from the junction box causing the battery in the control unit to go dead.  It would be a good installation practice to mount the junction box on a wood surface and then staple each cable to the wood so there's no way a cable movement can unplug a connection.


Peet Brothers Ultimeter 2100
                Weather Station

Peet Brothers Ultimeter 2100
                Weather Station
Junction Box

Jun 10, 2011 - there have been two occasions when the power plug has slipped out of the jack, causing the display internal 9V battery to be run down.  Some method of strain relief is needed to keep this from happening.
Peet Brothers Ultimeter 2100
                Weather Station
Wind Speed and Direction

Note:  This is the old one that's small.
This is a patented design where there's only 4 wires for both wind sped and direction.  The Heathkit wind speed and direction system uses a big cable of wires to handle the same function.

There are a couple of problem with it.
1) In order to get a wind direction reading there needs to be enough wind to turn the cups.  If the cups are not turning then there's no direction indication.  In the Heathkit system the wind direction is very sensitive to mild gusts and so even when the cups are not turning you can tell something is happening.

2) The cups do not turn until the wind is well above 5 MPH, so for most of the time there's no wind information of any kind.

That's why the new version of the 2100 uses much a much larger vane and cups, plus maybe a different mechanical design.

The Heathkit units uses ball bearings.
Peet Brothers Ultimeter 2100
                Weather Station

Peet Brothers Ultimeter 2100
                Weather Station
Outdoor Temperature Sensor
Not used, replaced by combined Temp-Humidity sensor.
Peet Brothers Ultimeter 2100
                Weather Station
Outdoor combined Temp & Humidity sensor
Peet Brothers Ultimeter 2100
                Weather Station
Tipping Bucket Rain Gauge
Peet Brothers Ultimeter 2100
                Weather Station
In order to get the tipping bucket rain gauge to fit onto the mast bracket the four mounting holes in the TB rain gauge need to be drilled out to 3/16" so they will fit on the studs.

The two large holes in the bottom of the bracket are directly below the water outlets in the TB rain gauge.
Peet Brothers Ultimeter 2100
                Weather Station
12 VDC @ 400 ma Wall wart power supply
Peet Brothers Ultimeter 2100
                Weather Station
Mounting parts for the Conroller

Wind speed cups and mast mount clamp
Radio Shack TV Mast
Radio Shack TV mast
Radio shack TV Mast Tripod
Radio Shack TV Mast Tripod
Installed in living room, rather than try an install on roof.  This way all the quirks can be addressed and the system tested.

Confirmed that the wind speed and direction functions work.


Did not confirm the tipping bucket worked!  Now that it's on the roof I'm not recording any rain.

Shorting the rain connector in the junction box causes the control to display 0.01" increments for rain fall, so there's a problem with the tipping bucket.

A problem showed up when trying to set the leap year number (0 default, 1, 2 or 3 options). 
The battery icon is blinking.  This happens when the backup 9V battery is missing or dead.
In my case the battery is fresh, which can be proved by pulling the power supply plug and seeing that the display stays on.
For some reason the keyboard/display unit does not see the battery but does use it's power.  This seems to prevent entering setting data.
 - - - -
"Press "Clear" and "Alarm" button simultaneously to initate battery check
function. In a few seconds, the flashing battery symbol should go out"
The flashing battery symbol will also go out after the next midnight reset.
30 Oct 2010 - Having called some roofers to make a repair and seeing them on the steep slope of my roof it occurred to me that they were the ideal people it install the tripod.  Much safer than me trying to climb up there.
See photo at top of page for the wind speed and direction plus tipping bucket rain gauge.

This is the old model (= good price on eBay) that has the small wind cups and small wind vane so it does not start till the wind speed gets to say 5 MPH.  I can see tree branches moving in a light wind without an indication on the control.

The controls are not intuitive.  That's to say you need the owners manual nearby to do anything.

WSF-10049 RJ-12 to DB-9 Computer Cable is required to connect to PC.

The cable is made up of two parts:
* DB-9f to RJ-12 adapter (154-0966F)
* 15' RJ-12 cable (6P6C)

I tried both of these programs and neither one works very well.

Note:  It later turned out that the problem may have been because I was using a USB-RS-232 converter.  When I make a direct RS-232 connection Virtual Weather Station works, and I lik it enough to buy, so
have not gone back and tried the two programs that did not work with the converter.
To go with the cable PC software is needed.
Weather-Display - would not work
Weather View32 - displays unstable

Ambient Virtual
                  Weather Station default screen
Virtual Weather Station - can operate with the Ultimeter 2100 in either loggingh mode or Complete Record Mode.  Was having what may be communications problems while in Complete Record Mode so have switched to the much shorted data of the Logging Mode.
7 Nov 2010 - the trial version of Weather-Display only partially works.  No barometric pressure and the other readings look bogus.  Maybe related to getting both the 2100 in the correct mode (Data Logging, Packet, Complete Record or Modem) as well as the settings in the setup panel of W-D.

Using Hyperterminal (2400-8-N-1) you can see the 40 character total Data Logging mode data or the 452 Character total Complete Record Mode data.

The problem was the Serial-USB converter.  Connecting the weather station directly to the computer COM 2 port solved the problem
VWS weg pages:
wx.htm    this looks like the screen I see on the computer
Daily.htm   statistics
usa.htm  U.S.A.

7 Nov 2010 - The rain gauge may or may not be working.  It's raining, but the 2100 display shows 0.00in.  Have a jar outside to see if there's more than 0.01" of rain.

19 Nov 2010 Non Working Ultimeter Tipping Bucket Rain Gauge
                  Working Ultimeter Tipping Bucket Rain Gauge
The problem is at the left of the red socket.  The idea was to just plug in the wire leads from the reed switch and 100 Ohm resistor to make an electrical connection.  BUT, the clear potting wicked into the socket and insulated the two wires making the rain gauge non fuctional.

When you tip the bucker you can hear the reed switch open/close.
Fixed Ultimeter Tipping Bucket Rain Gauge
                Ultimeter Tipping Bucket Rain Gauge
The fix was to solder the two wires toghther.
2 cups of water = 0.32"
500 ml of water = 0.33"

Tipping Bucket Rain Gauge Theory

I.D. of funnel = 8.073" (for 0.01" TB rain gauge)
Area of funnel = 51.187 sq in
1"      of rain looks like 51.187 cu in. The funnel size determines the multiplication factor, so the same bucket can be used in different gauges.
0.01" of rain looks like 0.51187 cu in
2 cups = 28.875 cu in
28.875cu in / 0.51187 cu in = 56.41 tips
The rain gauge counts each time the bucket changes position, i.e. twice per cycle.

The Peet Bros page says 9 to 11 cc per tip.  10 cc = 0.61 cu in which is off from 0.511 cu in.  Why?

So with 500 ml should count 50  (45 to 55) tips.  The funnel slows down the water so how fast it rains should not effect this result.
6 Jan 2011 Frozen Waterin Rain
                Catching Jar

6 Jan 2011 Frozen Waterin Rain Catching Jar  outdoor temp 30 F

Cloud Sensor

Not incorporated into this station is a cloud sensor.  My prior attempts at a cloud sensor have had a very wide look angle at the sky.  One was a Peltier device that has a voltage output that depends on the relative temperature of the sky and ground with a hemispherical view of the sky.  The IR temperature sensor has a 1:1 beam, i.e. about a 90 degree look angle.

It would be better if the cloud sensor had a narrow look angle so that when a strip chart graph was made of the sky temperature vs. time you could see individual clouds.  An idea that's in progress (Jan 2011) is to use a 12" parabolic reflector Edmond Optics NT53-875 and a thermopile.  An alternative long IR sensor would be a Melixis TO-5 packaged unit, but it's more difficult to incorporate.  The sensitivity could be increased by using the 18" or 24" reflectors, but at added cost.
Honeywell Q313 A
        1170 Powerpile Generator 750 Millivolt 35" Lead Length PG9
        Cartridge Powerpile ANS Z21.20 Auto. Ignition


4969358 Electronic altimeter/barometer, (Peet Bros.), Nov 13, 1990 -
5001929 Electronic altimeter, (Peet Bros.), Mar 26, 1991 -
5033402 Metric/English orometer, (Peet Bros.), Jul 23, 1991 - altimiter with either feet or meter indications
5231876 Method and apparatus for wind speed and direction measurement, (Peet Bros.), Aug 3, 1993 - instead of using a bunch of reed switches and a multi conductor cable from the wind driection indicator (like the Heathkit ID-4001) only two sensors are used.  One for the wind speed and one for the wind direction.
5361633 Method and apparatus for wind speed and direction measurement, (Peet Bros.), Nov 8, 1994 -




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