Soundcard as Analog to Digital Converter

PC based water level control system using soundcard as analog to digital converter. Water level controllers ensure that appropriate amounts of water or fluids are dispensable or maintained in various agricultural and industrial applications. However, they are extremely expensive, costing as much as US$1,695.00 for flexible and programmable units. The main cost accounts for data acquisition cards and software.

The study developed a PC based water level monitoring and control system using the computer sound card as the analog-digital converter. The water level was monitored using silver rod (Cu-Ag alloy) as sensor. An electronic signal generator circuit was fabricated to produce the sine wave signal analog equivalent to the silver rod resistance changes for input to the computer. A graphical user interface (GUI), using Visual Basic 4 programming language, was developed to provide visual and graphical output on the computer monitor for user interaction with the system. The prototype provided for a system that was able to do the following:

1. measure the water level within acceptable range of the manual height indicator;
2. alter parameters of desired water height according to user need; and
3. provide a log that determined trending of water use.

This provides for an accurate, effective and customizable water level control system at about 65% less than the cost of commercial units as an old PC with licensed software.

Further clarification of the procedures and results should be directed to the researchers and adviser.