Assembly

Component

Source

Cost (US$)

Transmitters

ProMini microcontroller board

Sparkfun electronics

10

BMP180 barometric pressure breakout board

Adafruit industries

10

HTU21D relative humidity breakout board

Sparkfun electronics

15

TCS34725 color-to-light breakout board

Adafruit industries

8

Watermark 200SS soil-moisture sensor

Irrometer company

30

miscellaneous

8

Receiver

Diavolino microcontroller board

Evil mad science

15

Ethernet shield

ITEAD studios

20

OpenLog serial datalogger

Sparkfun electronics

25

DS1307 real-time clock

Maxim integrated

2

Prototype shield

Sparkfun electronics

10

Xbee adapter

Adafruit industries

10

miscellaneous

7

Xbee series 1 radio modems

Digi international

20

Total cost

Transmitter #1

108

Transmitter #2

121

Receiver

109