Final Assembly
1-Wire Outdoor Sensor/Interface Kit

Refer to the layout diagram for clarification of parts placement. All references to up, down, left, and right assume that you are looking at the PCB with the silkscreen TAPR logo at the lower right-hand side of the board. All components are mounted on the top of the PC board.

Conformance Coating

It is highly recommended that a conformance coating of some type be applied to the board before installing the unit outdoors. If not protected, the humidity sensor will fail after a period of time due to leakage currents. The other integrated circuits, especially the 1-Wire devices will eventually have problems as well. A commercial grade of conformance coating would be ideal. If available, be certain it will not damage the humidity sensor. Check application notes and spec sheets on Honeywell's site to check for compatibility.

If you don't have access to a commercial grade conformance coating, hot glue can serve as a very viable substitute. It won't look very pretty, but it will work! Note that any exposed pads and traces should be covered as well as the ICs. Experience has shown that traces that carry even small amounts of current can and will be eaten away by corrosion or cathodic action. In applying the glue around the humidity sensor, make a dam up around and just touching the bottom of the humidity sensor completely sealing the leads coming up from the board to the sensor. This will take some patience. It is suggested that a trial coating be made on a power transistor with a TO-220 case from the junk box mounted on piece of perf board. Be careful not to get any of the glue on the active sensor area!


  If a small plug exists at the end of the fan power leads, clip it off as close as possible to the plug. While this may seem to leave more lead than is necessary, it will prove helpful should you need to remove the fan to service the components beneath.
  Strip 1/8" insulation off both the fan leads and tin the ends.
  Solder the red lead to J3 pin 1 (square hole) and the black lead to the remaining hole.
  Attach the four 1" 6-32 threaded spacers to the sensor board at the points labeled asp_mt on the pictorial with four 6-32 x ¼" screws. The spacers should be on the top of the PC board (component side). Leave the screws somewhat loose at this point.
  Place the fan on top of the spacers so that the manufacturer’s label is facing up. There should be an arrow on the side of the unit indicating the direction of air flow. It should point up, away from the sensor board.
  Attach the fan to the spacers using 6-32 x ¼" round head screws.
  Snug down all screws, both top and bottom (eight screws total).

Top View

At this point, the power connector and supply leads should be assembled and connected to the board at P1. A female header with contacts is provided for this purpose.

The fan is polarity sensitive and will run on anywhere from about 8V-12V DC. 9VDC wall transformers work well and supply about 12VDC to the fan (most wall transformers normally supply several volts over their rated output). The fan draws approximately 150 mA, so use a transformer rated at 200 mA or higher.

Aspirator Power/Control

WXN Weather Server - Consult the server's documentation on how to connect the aspirator to the X1W-1's control output.

All Other Users - Simply connect the power leads to a +12VDC power source capable of supplying approximately 200 mA. Your aspirator will run continuously (and that is not a problem).

Push-On Shunts

If you did not install the EMP/Rain Gauge option, the push-on shunts that enable the the 1-Wire® devices will need to be installed. If you have already installed the shunts, proceed with the final installation.

The purpose of the shunts is for sensor setup in the T-238/T-238+ firmware and trouble-shooting. Install the following push-on shunts as required at JMP1.

  Install push-on shunts at H and T
Perform the following step only if the EMP/rain gauge interface is installed...
  Install a push-on shunt at G/E


Congratulations! You have completed the assembly and initial testing of your 1-Wire® Outdoor Sensor/Interface kit. Proceed to the installation.