I have taken the short time available and worked up a budget table for this project. And just like any engineering project, I am over budget and behind schedule. I knew that I would not be able to build a prototype cheaply. And I think I will be on budget for a production system. Take a look for yourself:
| Item | Unit Cost | # of Units | Total |
| Arduino | 29.95 | 2 | 59.90 |
| HIH-4030 Humidity Sensor | 16.95 | 1 | 16.95 |
| TMP102 Temperature Sensor | 5.95 | 1 | 5.95 |
| 2 Gallon Round Up Tank Sprayer | 19.97 | 1 | 19.97 |
| Sprinkler Solenoid | 14.97 | 1 | 14.97 |
| Proto Shield | 12.5 | 1 | 12.5 |
| Breadboard Wire Kit | 5.99 | 1 | 5.99 |
| Transistor 2N2222 (15-pack) | 2.59 | 1 | 2.59 |
| Diode 1N4004 (2-pack) | 0.99 | 2 | 1.98 |
| 5V 1 Amp Relay | 4.69 | 2 | 9.38 |
| Universal Breadboard | 8.99 | 1 | 8.99 |
| 1K-Ohm resistors (5-pack) | 0.99 | 1 | 0.99 |
| 9V Battery clip (5-pack) | 1.99 | 1 | 1.99 |
| PCB Screw Terminals (4-pack | 1.99 | 1 | 1.99 |
| Project Box | 3.69 | 1 | 3.69 |
| Electrical Receptacle | 0.59 | 1 | 0.59 |
For a grand total of: $168.42
I had to buy a second Arduino because I fried the first one. I hate electronics. On that note, I still haven't solved the solenoid issue. I actually haven't even worked on it, but that doesn't change the result. Today, I purchased the last of the necessary equipment to get the daylight automated, which will be helpful for when I have to leave before the wife gets up so she doesn't have to remember to turn on the light. I plan the have this up and running this weekend. Until next time, continue being creative.
