Transcript Mid-Semester Presentation Senior Design 1 October 8, 2009 RF

Mid-Semester Presentation
Senior Design 1
October 8, 2009
Randall Vaughan
Zach Jordan
Sine Wave
Generation
Op-Amp
Configuration
Phase Shift
Detection
Layout and Design
Electrical
Engineering
Caroline Quijano
Computer
Engineering
Jonathan Lynch
Layout and Design
Sine Wave
Generation
Website Design
Circuit Board
Production
Electrical
Engineering
Electrical
Engineering
Op-Amp
Configuration
Problem
 Solution
 Constraints

• Technical
• Practical
Alternatives
 Progress

Dr. Jack Liu of the Department of
Forestry Products requires the use of
a portable RF moisture content
sensor
 Needs a smaller, inexpensive,
repackage of his patented prototype

The Actual RF Apparatus
[1]

Repackage his working prototype
by using integrated circuits to
replace test-bench equipment.
Power
Supply
Display
Amplifier
Microcontroller
Waveform
Generator
Transmitting/
Receiving
Sensors

Technical Constraints

Practical Constraints
Constraint
Description
Voltage Level
The signal applied to the sensors must measure 80V (+/- 5V)
peak-to-peak.
Frequency
The sensor must produce a 250 kHz (+/- 5 kHz) sine wave.
Interface
The device must have a simple user interface in order to display
its measurements.
Data Logging
The device must be able to store at least 130 kilobytes of
moisture content readings.
Sensor Array
The device must use seven 4 in. by 4 in. sensors configured in
an array.
Type
Constraint
Environmental
Durability
Health and
Safety
Safety
Description
The device must be able to withstand various
industrial conditions such as dust and electrical
noise.
User contact with high voltage signals must be
prevented.


[2]
Sensor must
withstand debris,
electrical noise,
and moisture
Sealed, electrically
shielded, rugged
housing



Isolated high
voltages
Partition that
separates gap
from user
interface
Appropriate
warning labels
displayed
[3]
Wall Plug
Voltage
Range
Low
Current
Output
Switching
Power Supply
Charge Pump
-
DC/DC
Converter
-
-
-
Temperature
Stability
Discrete
Oscillator
No
Distortion
-
Integrated
Circuit
Analog Filter
Circuit
-
-
Affordability Development
Time
Operational
Amplifier
Discrete
Amplifier
-
Phase
High
Resolution
Range Voltage
Input
Timers
Logic
Gates
-
August
Research
Hardware
Design
Prototyping
Testing
September October November



Configured XR2206 Waveform
Generator to output 250 kHz sine
wave
Ordered Power Supplies and
connectors
Produced PCB for testing of PA78
350V Operational Amplifier
Programmable
Oscillator
XR2206 Waveform
Generator
Mean Well
PS-05
OPA445 90V
PA78 350V





[1] Radio Frequency Evaluation of Oriented Strand Board, by Xiaojian Liu, Starkville MS.
[Online]Available: http://chevelle.its.msstate.edu:6777/attach/XiaojianLiuDissertation%20%20RADIO%20FREQUENCY%20EVALUATION%20OF%20ORIENTED%20STRAND%20BOARD.p
df?sid=&mbox=INBOX&charset=escaped_unicode&uid=2012&number=7&filename=XiaojianLi
uDissertation%20%20RADIO%20FREQUENCY%20EVALUATION%20OF%20ORIENTED%20STRAND%20BOARD.p
df.
[2] Microsoft Office Online, Clip Art. 2009. http://office.microsoft.com/enus/clipart/results.aspx?qu=warning&sc=20.
[3] Google Images. 2009.
http://albas.id.au/images/temp/Caution%20electrical%20shock%20hazard%20inside%20sign
.bmp.
[4] Forestry Facts: Guide for Using the Oven-Dry Method for Determining the Moisture Content
of Wood, by R.S Boone and E.M. Wengert, Madison, Wisconsin, 1998. [Online] Available:
http://forest.wisc.edu/extension/Publications/89.pdf.
[5] Wood Products Notes: Methods of Moisture Content Measurement in the Lumber and
Furniture Industries, by Phil Mitchell, Raleigh, NC. [Online]Available:
http://www.ces.ncsu.edu/nreos/wood/wpn/methods_moisture.htm.

[6] United States of America. Federal Communications Commission. Code of Federal
Regulations, Title 47, Part 15. Washington, D.C.: Federal Communications Commission, 2008.

[7] Panel Layup Operations, by Phil Mitchell, Raleigh, NC. [Online] Available:
http://www.ces.ncsu.edu/nreos/wood/RMOG/Adobe/Panel.pdf.