The 1-Wire® outdoor sensor/interface kit was designed to be used with the TAPR T-238 APRS Weather Station or N4XI's Linux based WXN weather server over APRS. It should work with any other 1-Wire® based software as the design is based on the original Dallas Semiconductor 1-Wire® Weather station. The humidity sensor with the kit is an improved version over the original part. It has proven stable with good accuracy over a wide range of temperatures and conditions.

If the X1W-1 inside sensor/interface kit was purchased at the same time, you have the option of installing the EMP/rain gauge interface on this board rather than on the inside board. See the X1W-1 manual on the TAPR web site for more information.

The board also features an aspirator (fan) to improve humidity readings. The fan employed uses ball-bearings which should give a longer life-span than sleeve bearings.

Firmware/software support for this kit is given below:

n Y
Temperature Y Y
Humidity Y Y
Rain Gauge Y n/a
n Y

You can view the completed board, including the EMP/Rain Gauge option, by clicking on the camera.

The humidity sensor must be protected from strong light and direct exposure to the elements. The mounting centers for the sensor board match up to the Davis Instruments Passive Radiation Shield, #7714. The shield works well. If you do not wish to use the Davis shield, some type of enclosure must be fashioned to house the board and protect the humidity sensor. The X1W-2 kit does not come with an enclosure.

Latest changes and other information on the X1W-2 is available at either of the following two sites:

The T-238, T-238+, X1W-1, X1W-2 and X1W-4 are discussed on the Weather Special Interest Group (WXSIG). You can join WXSIG via the web by clicking here.


The Tucson Amateur Packet Radio X1W-2 Kit was made possible by the efforts of:

John Bennett, N4XI – Conceptual and PCB Design
John Koester, W9DDD – Project Manager
Steve Bible, N7HPR – Assistant Project Manager
Joe Borovetz, WA5VMS – Parts Liaison
Dwight Hazen, WB9TLH – Beta Tester
Will Beals, N0XGA – Beta Tester