Directional Microwave Radar Vehicle Motion Sensing · PDF fileDirectional Microwave Radar...
Transcript of Directional Microwave Radar Vehicle Motion Sensing · PDF fileDirectional Microwave Radar...
Directional Microwave Radar Vehicle Motion Sensing System
Eric Canniff
Cody Johnson
Zach Whitney
May 2014
Department of Electrical Engineering
University of Minnesota Duluth
Duluth, MN 55812
Faculty Advisor: Taek Mu Kwon
Approved________________________________________ Date_______________
Advisor’s Signature
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Table of Contents
List of Figures .................................................................................................................................. iii
List of Tables ................................................................................................................................... iv
List of Equations .............................................................................................................................. iv
Abstract ........................................................................................................................................... v
1. Introduction ................................................................................................................................. 1 1.1 Vehicle Detection Technology Review: ..................................................................................................................................... 1 1.1.1 Pneumatic Tube: ............................................................................................................................................................................. 1 1.1.2 Piezoelectric Cables ....................................................................................................................................................................... 1 1.1.3 Active Infrared Sensors ................................................................................................................................................................ 2
2. System Design .............................................................................................................................. 3 2.1 Choosing technology ........................................................................................................................................................................ 3 2.2 Hardware design ................................................................................................................................................................................. 3 2.3 Interrupt Coding ............................................................................................................................................................................ 10 2.4 Calculating Speed and Direction ............................................................................................................................................. 11
3. Experiments ............................................................................................................................... 13 3.1 Testing Set-up .................................................................................................................................................................................. 13 3.2 Data Collection ................................................................................................................................................................................ 13 3.3 Data Processing ................................................................................................................................................................................ 13 3.4 Problems Encountered ............................................................................................................................................................... 13 3.5 Analysis of Experimental Results ........................................................................................................................................... 17 3.6 Note on LCD Power Consumption ......................................................................................................................................... 18
4. Professional Components ........................................................................................................... 19 4.1 Economical Concerns .................................................................................................................................................................... 19 4.2 Environmental Concerns .............................................................................................................................................................. 19 4.3 Sustainability Concerns ................................................................................................................................................................. 19 4.4 Manufacturing Concerns .............................................................................................................................................................. 19 4.5 Ethical Concerns .............................................................................................................................................................................. 19 4.6 Health Concerns & Safety Concerns ........................................................................................................................................ 19 4.7 Social Concerns ............................................................................................................................................................................... 19
5. Observations .............................................................................................................................. 20 5.1 Issues with microwave sensor ................................................................................................................................................ 20 5.2 Traffic Congestion ......................................................................................................................................................................... 20 5.3 Weather Issues ............................................................................................................................................................................... 20 5.4 Microcontroller Issues ................................................................................................................................................................ 20
6. Conclusion .................................................................................................................................. 21
References: .................................................................................................................................... 22 [1] Amplifier Circuit ............................................................................................................................................................................... 22 [2] HB100 Datasheet ............................................................................................................................................................................. 22 [3] Arduino LCD Shield ......................................................................................................................................................................... 22 [4] Arduino microSD Shield ................................................................................................................................................................ 22
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Appendix A: Bill of Materials .......................................................................................................... 23
iii
List of Figures
FIGURE 1 AMPLIFYING CIRCUIT [1] .............................................................................................................................................. 5
FIGURE 2: SHIELD TO ARDUINO PIN-‐OUT ................................................................................................................................. 6
FIGURE 3: ALUMINUM SHIELD ....................................................................................................................................................... 7
FIGURE 4: AZIMUTH WAVES .......................................................................................................................................................... 8
FIGURE 5: INSIDE (LCD [3] UPPER LEFT) .................................................................................................................................. 9
FIGURE 6: OUTSIDE VIEW OF BOX AND SCREEN ....................................................................................................................... 10
FIGURE 7: BOX DISPLAY ................................................................................................................................................................ 14
FIGURE 8: RECORDING AND STAND SETUP ................................................................................................................................ 15
FIGURE 9: ACTUAL AND EXPERIMENTAL DATA ......................................................................................................................... 16
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List of Tables
TABLE 1: ROADSIDE TEST RESULTS ........................................................................................................................................... 16
TABLE 2: SPEED BIN COUNT ........................................................................................................................................................ 17
List of Equations
EQUATION 1: SPEED VALUE ......................................................................................................................................................... 12
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Abstract
The project's objective was to design, build, and test a prototype that senses directional
volume and estimates the speed of traffic using a low-cost microwave transducer chip. The
reasoning behind creating this system was to produce a low-cost system that can obtain
directional counting using a single sensor for two-lane roads. The system is constructed using a
low-cost microwave radar chip and an Arduino micro-controller to log the data. This report will
cover how we were able calculate the direction and the speed of the vehicles using the output
given from the transceiver. Analysis of the experimental results and conclusions are provide
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1. Introduction The objective of this design project was to design a prototype to detect the direction
volume and traffic speed using a microwave radar transceiver. The reasoning behind this
project was to create a low-cost version of existing vehicle sensing microwave radar systems.
This system will work well in all weather conditions due to the use of a microwave radar
technology. Many other types of vehicle sensing technologies can be affected by weather and
environmental conditions, such as, rain, snow, fog, smog, or lack of daylight. The bill of
material for our project has not exceeded $200 therefore producing an economical system.
1.1 Vehicle Detection Technology Review:
1.1.1 Pneumatic Tube:
One of the simplest methods of measuring traffic speed and flow is the pneumatic tube.
A tube, fixed to the ground has a sensor on the end and it counts the number and time of pops
using a pressure sensor. Easily broken as well as they can be tampered with. They cannot be
used in places where there is snow due to being plowed away. It is an intrusive sensor since
tubes must be tied to the pavement surface.
1.1.2 Piezoelectric Cables
Like Pneumatic tubes these cables are mounted on the roads surface. Instead of air they
transfer mechanical energy of car tires rolling over to electrical energy. These cables share the
same disadvantages noted above in the pneumatic tube section.
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1.1.3 Active Infrared Sensors
These lasers transmit multiple beams to monitor vehicle position, speed, and class.
Unlike microwave transmitters, many things, such as, snow, rain or blowing leaves, affect
active infrared systems. They require a clean line of sight distance to the object.
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2. System Design
2.1 Choosing technology
Based on the requirements of a low-cost design we selected an Arduino based system
because it runs on a battery and has a micro-SD [4] storage device. A low-cost microwave
sensor ($5), HB100 [2], was selected as our transceiver. We encased our circuit board and
components in a weather proof box to ensure its safety in harsh weather conditions.
2.2 Hardware design
The Arduino microcontroller used has 6 analog pins that can be set to either inputs or
outputs. These pins have a resolution of 10 bits ranging from 0 to 1023. Also, the
microcontroller has flash memory that is a size of 16 KB. This microcontroller has a
recommended input voltage of 7-12 volts that work well with a battery source. Arduino
microcontrollers are coded in a C like language and provide Arduino’s own programming
environment. The codes can be uploaded from a PC via USB and stored on the flash memory.
Along with the Arduino we used a LCD [3] pre-designed shield made for the Arduino.
This shield also includes 5 buttons for use to control desired functions within the Arduino. The
LCD [3] screen is used to display the current state of the program, along with data that has been
collected. This is helpful for real-time analysis of whether or not the traffic data is accurately
being collected. A micro-SD shield [4] is used for storing data files.
The HB100 [2] microwave transceiver is used for our microwave radar sensor. This
sensor has a low-cost (only 5$), making our system very affordable. This sensor outputs a
voltage in relation to the distance and speed of the object moving in front of the sensor. This
sensor incorporates both the transmitter and the receiver. It also includes an antennae array for
both the transmitter and receiver. The output of the sensor is in the low millivolt range so an
amplifier circuit [1] was needed. For this we used a slightly modified version of the given
circuit from the HB100’s data sheet [2]. The circuit includes a two-stage op-amp and filtering
circuits to reduce noise. We used a dual packaged op-amp with a very low input bias, a high
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CMRR, and a very high frequency bandwidth. The modified circuit portion included added
filtering to the supply voltage and dual output configuration. The dual output configuration
gave us an output for distance in relation to DC voltage output and a frequency output that
gives us a relation to the speed of the object. A comparator that switches the voltage from high-
to-low, giving us a near digital signal, produced this frequency.
A single 12-volt battery powers this system. The higher voltage was needed to run the
backlight on the LCD shield and all the components without a significant power drop when the
LCD backlight is on. The voltage regulation was handled by Arduino’s on board voltage
regulators. The Arduino supplies the necessary 3.3-volts for the micro-SD [4] reader and the 5-
volts for the LCD [3] shield and the sensor circuitry. The circuit is shown in Figure 1 and
Figure 2.
We modified our design by adding a metal shield. (See Figure 3) The goal was to
change the sensor waveform. This aluminum shield allowed us to stand behind the sensor and
only record data from in front. Before we had the shield installed we were being picked up by
the sensor and recorded.
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Figure 1 Amplifying Circuit [1]
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Figure 2: Shield to Arduino PIN-OUT
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Figure 3: Aluminum Shield
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Before Shield After Shield
Figure 4 shows the side waveforms. The graph on the left is without the shield and it
shows that it can sense behind itself. We found this feature to hurt our analysis because
something as simple as looking at the computer to see if cars are recording correctly, would be
recorded like we were a passing car. The addition of the shield modified the detection field as
shown in the right graph. This allowed us to monitor our data recording live and let others, such
as pedestrians, walk behind the sensor without contaminating our results.
--Changing of Capacitor from 10uF to .1uF
We changed out the capacitor size from 10uF to .1uF to get a faster discharge time. By
shortening the amount of time it takes to discharge we are able to get a faster reset time from
our sensor. The amplifying circuit [1] with a 10uF capacitor would read multiple cars in a row
as one large car. The voltage would increase and this would not match our physical count of the
cars that went by. Integrating the smaller capacitor produced the speed needed to record
multiple cars in a row.
Figure 4: Azimuth Waves
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--Relocation of LCD [3] screen.
The Arduino LCD [3] screen was moved to fit into our box window. Using a trail
camera box we know we have a secure seal from the elements. It already had a window for the
camera flash, but we replaced this with our LCD [3] screen so we can see the output in real
time. Figures 5 and 6 show the LCD [3] wiring and screen relocation.
Figure 5: Inside (LCD [3] Upper Left)
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Figure 6: Outside View of Box and Screen
As you can see in Figure 6 and Figure 7, our case is well sealed and has a nice clean
readout of the LCD [3] screen. The screen was coded to read speed blocks, with how many
number of cars. With a push of a button we can change the screen to display number of
vehicles in each direction.
2.3 Interrupt Coding
Below is our interrupt code used in the counting and categorizing process. This was the most
difficult part of our project and was also where we had to make the decision to accept error
from tailgating cars and them being too slow. void count()
{ detachInterrupt(freqInt);
dVal = analogRead(distPin);
if (dVal > 600 && Counter == 0)
{ highVal = 0;
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lowVal = 1000;
if (Counter == 0)
{ while(i <= arrLength)
{ distArr[i] = analogRead(distPin);
if(distArr[i] > highVal)
{ highVal = distArr[i];
highCount = i; }
if((lowVal > 550) && (distArr[i] < lowVal))
{ lowVal = distArr[i];
lowCount = i; }
save = true;
i = i + 1;
delay(950); }
car = true;
i = 0;
if(save)
{ if(distArr[highCount] < farCloseLimit)
{ far = far + 1; }
else if(distArr[highCount] >= farCloseLimit)
{ closer = closer + 1; }
range = ((long(highVal)-long(lowVal))/(long(lowCount) - long(highCount)));
if (range < twentyLower)
{tenCount++; }
else if (range >= twentyLower && range < twentyUpper)
{ twentyCount++ ;}
else if (range >= thirtyLower && range < thirtyUpper)
{ thirtyCount++; }
else if (range >= fourtyLower && range < fourtyUpper)
{ fourtyCount++; }
else if (range >= fiftyLower && range < fiftyUpper)
{ fiftyCount++; }
else if (range >= sixtyLower && range < sixtyHigher)
{ sixtyCount++; } } }
Counter = Counter + 1;
delay(300); }
else
{ car = false; } }
2.4 Calculating Speed and Direction
When a vehicle is detected, the distance voltage is recorded and determines if the vehicle
is approaching or driving away. A higher voltage represents an oncoming vehicle while a lower
voltage indicates a leaving vehicle. These voltages are stored in an array and the high value is
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used to determine the direction. This array is then used for speed estimation by inputting it into
an equation:
Equation 1: Speed Value
𝑆𝑝𝑒𝑒𝑑 𝑉𝑎𝑙𝑢𝑒 =𝑉!!"! − 𝑉!"#𝑖!!"! − 𝑖!"#
𝑉!!"! = 𝐻𝑖𝑔ℎ 𝑉𝑎𝑙𝑢𝑒 𝑜𝑓 𝑆𝑡𝑜𝑟𝑒𝑑 𝐴𝑟𝑟𝑎𝑦,𝑉!"# = 𝐿𝑜𝑤 𝑉𝑎𝑙𝑢𝑒 𝑜𝑓 𝑆𝑡𝑜𝑟𝑒𝑑 𝐴𝑟𝑟𝑎𝑦
𝑖!!"! = 𝐿𝑜𝑐𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝐻𝑖𝑔ℎ 𝑉𝑎𝑙 𝑖𝑛 𝐴𝑟𝑟𝑎𝑦, 𝑖!"# = 𝐿𝑜𝑐𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝐿𝑜𝑤 𝑉𝑎𝑙 𝑖𝑛 𝐴𝑟𝑟𝑎𝑦
The above equation outputs a value between 0 and 8. This number roughly determines
the speed bin that the vehicle should be in.
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3. Experiments
3.1 Testing Set-up
To encompass a high volume flow of traffic we tested at 2 pm and 3 pm on 19th Ave
East. For low volume we tested the same road at 7 pm. This test was done during overcast skies
with no precipitation and a temperature of roughly 40 degrees Fahrenheit. 19th Ave has a speed
limit of 30 MPH and is a two lane road with traffic in two directions.
3.2 Data Collection
We collected data from the side of the road where it will not get into the way of any cars
or be a distraction. We take data readings for about an hour. Once again on 19th Ave, here in
Duluth. As a base reference we used one of our cars so we know the length and speed of the car
these initial data helped writing codes for translating voltage and frequency measurements to
speed and direction.
3.3 Data Processing
Once collected we interpret the data from a PC, running them through a spreadsheet.
The spreadsheet included logging by speed bin, time of day, and direction of flow.
3.4 Problems Encountered
During testing we ran into a few problems, cars going slow, tailgating, and having
coding issues. For cars tailgating or traveling below 10mph we found that they were
categorized under the Far count. This was due to how we had our interrupt. We had troubles
with our interrupt freezing our system when we tried to create a custom delay in a loop. Below
are our test setup and results.
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Figure 7: Box Display
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Figure 8: Recording and Stand Setup
The system is placed alongside the road with Cody manually recording the count of the vehicles during the test.
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Table 1: Roadside Test Results
Figure 9: Actual and Experimental Data
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Table 2: Speed bin Count
3.5 Analysis of Experimental Results
The accuracy on Test-1 and 2 was better because there was a higher volume of cars.
Test-1 was conducted at 2pm, Test-2 was 3pm, and Test-3 was at 7:30pm as seen in Table 1.
With fewer cars, the error increased. But the accuracy only went down by 5% for 82 less cars.
However Tests 1 and 2 were for a half hour each and Test-3 was for a whole hour of running.
In reference to Table 2 we have the results of speed categorization for Tests 1, 2, and 3.
It appears that there must have been an error caused by unknown factors to bump up the
majority of speeds into the 30-40mph bin of Test 1. Test 2 and 3 are much more relevant for
the traffic on the road. Also the higher speeds were not witnessed in person—no emergency
vehicles—but we believe these high numbers came from two cars passing at the same time.
Two cars passing at the same time would have increased the voltage to a large number and
divided it by a small number. Also in speed calculation you can see where the double cars are
missed, for example looking at Test 3 we counted 271 cars counted in the speed loop but the
actual number of cars that passed was 314. This leaves us with a 13% error for Test-3. The
errors for volume counting in the other two tests were Test 1: 16% over, and Test 2 was 15%
under the actual count Figure 9 shows this relationship.
After running three separate experiments our data concludes that we reached 14.2%
error for counting car direction. We tested on a high-speed road with three lanes—one shared
turn lane in the middle—and we found that reaching the far lane was too difficult for our
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sensor. For our level of sensitivity we were able to calculate a cars speed within 10mph speed
brackets. The error mainly came from tailgating cars because our circuit would not discharge
fast enough. We had a choice to make, either have it sensitive enough to read tailgating cars
while lacking in our speed reading, or we could lower the sensitivity and miss the cars too close
together, but able to categorize the speed correctly.
3.6 Note on LCD Power Consumption
While running with the LCD [3] screen backlight on our system consumed 1.56W.
While running with the backlight off we consumed 1.3W. Our batteries are rated for 76.8WH
which would give us a battery life around 60hr while running with the light off. There isn’t a
need to run with the light on when you leave it on the side of the road. It is also recommended
to install an LCD [3] power-off switch which would entirely cut off the power
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4. Professional Components
4.1 Economical Concerns
The device we designed has a primary design objective of low-cost design. This device
is also efficient in the power consumption.
4.2 Environmental Concerns
The device currently has little to no environmental concerns. If the system was
implemented in a more permanent structure there could be concern in the construction of the
structure.
4.3 Sustainability Concerns
With the use of batteries as our power source we will be looking into the use of a simple
solar array to eliminate this concern.
4.4 Manufacturing Concerns
The device we are designing and all of the components are already mass-produced
however the design can be improved for the manufacturability.
4.5 Ethical Concerns
As far as we can see there are no ethical concerns involved with the implantation of our
device.
4.6 Health Concerns & Safety Concerns
The use and operation of this device could not be used in anyway to harm someone.
4.7 Social Concerns
The microwave system will not have any signal interference with any other electric
devices. It will come up on personal vehicle radar detectors but will not hurt the device.
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5. Observations
5.1 Issues with microwave sensor
We found this sensor to be a bit too cheap for the desired results. When trying to apply
the sensor to a larger road—more than two lanes—we couldn’t pick up the far lane cars. Even
after adding the aluminum antenna to focus the signal forward we could still not get the far lane
with the addition.
5.2 Traffic Congestion
If cars pass by too slowly they are counted twice. Larger vehicles, such as busses,
produce skewed results because they are picked up many times as well. Our sensor was not
sensitive enough to pick up these cars correctly and when we modified the code to be more
sensitive then we were getting poor results on the speed.
5.3 Weather Issues
Now microwave sensors in theory should not be able to pick up rain or snow. If
powerful enough they should only pick up bounces off of metal. In our case, during the testing
phases before we did our final experiments we were picking up raindrops falling off of trees
around the sensor. If we were to use a more expensive microwave sensor we do not see weather
being an issue.
5.4 Microcontroller Issues
When it came to coding interrupts we had issues with saving the cars in time and
keeping up with cars in a line. If we used a proper interrupt that could see the difference
between two cars close together we would have better results. There wasn’t a perfect algorithm
that could both sample and save quick enough and be accurate. Every time we tried to boost up
the results our microcontroller would fill up and freeze or it just wouldn’t record anything
correctly.
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6. Conclusion Looking at all of the factors that played into this project, one semester time limit, cheap
microwave sensor, and a wide open field to build on and explore, our group feels accomplished
with the outcomes. With an error of 15% in counting and just about the same for speed
categorization we believe the overall experience a success. Working with a $5 microwave
sensor that picked up raindrops, we were still able to complete this project with surprising
accuracy. Working with the Arduino and learning how to create a successful interrupt was our
largest challenge. The amplifying circuit [1] was a straight-forward build and we varied our
capacitor size to have it discharge faster in order to pick up cars quick enough. In the end we
would not recommend this device for a road more than two lanes wide and with high amounts
of traffic. If it were for metering at midnight to see how many people commute overnight, this
system would work wonderfully. Too many cars passing at one time threw off our counts and
cars going too slow had the same effects. This system would work better on rural low-volume
roads. With weather being a factor with the cheapness of the sensor you really cannot accept
the data as fact if you were to leave it out for the full 60hrs of its battery life. Our metering
system is applicable to rural low-volume roads and can count up to two lanes simultaneously. It
is not recommended for high-volume urban roads.
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References:
[1] Amplifier Circuit Limpkin's Blog. N.p., 9 Aug. 2013. Web. 6 Feb. 2014. <http://www.limpkin.fr/index.php?post/2013/08/09/Making-the-electronics-for-a-%247-USD-doppler-motion-sensor>.
[2] HB100 Datasheet Electronics, ST. AgilSense. N.p., n.d. Web. 4 Feb. 2014. <https://d9cq1vhji0gn4.cloudfront.net/blog/wp-content/uploads/wpsc/downloadables/HB100_Microwave_Sensor_Application_Note.pdf?21c71f>.
[3] Arduino LCD Shield LinkSprite. N.p., 17 Apr. 2014. Web. 6 Feb 2014. <http://linksprite.com/wiki/index.php5?title=16_X_2_LCD_Keypad_Shield_for_Arduino>.
[4] Arduino microSD Shield SparkFun. N.p., n.d. Web. 4 Feb. 2014. <https://www.sparkfun.com/products/9802>.
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Appendix A: Bill of Materials
Item%# Reference%# Part%Name Device%Name Manufacturer Distributor Quanity Unit%Price Extended%PriceDevice%Description Comments1 MC1 Arduino%Leonardo DEVC11286 Arduino Spark%Fun 1 24.95 24.95 MicroController Received2 MC2 Arduino%LCD%Shield DEVC11851 LinkSprite Spark%Fun 1 12.95 12.95 LCD%Button%Shield Received3 MC3 Arduino%SD%Shield DEVC09802 Spark%Fun Spark%Fun 1 14.95 14.95 MicroSD%interface%for%Arduino Received4 S1 HB100%Microwave%Sensor SLI15672904001 Agil%Sense Open%Impulse 1 4.85 4.85 10.525GHz%Microwave%Motion%Sensor%Module Received5 U1 Dual%OpAmp OPA2365AIDR Texas%Instruments DigiKey 1 2.73 2.73 IC%OPAMP%GP%RCR%50MHZ%DUAL%8SOIC Received6 U2 Comparator MAX9031AUK+TCTCND Maxim%Integrated DigiKey 1 0.95 0.95 IC%Comparator%Volt%SGL%SOT23C5 Received7 D1 Schottky%Diode 1N5818CTPCTCND Micro%Commercial%Co DigiKey 3 0.39 1.17 Diode%Schottky%30V%1A% Received8 C1,C10 Capacitor BC2665CTCND Vishay%BC%Components DigiKey 2 0.37 0.74 CAP%CER%0.1UF%50V%10%%RADIAL Received9 C6,C7 Capacitor BC2675CTCND Vishay%BC%Components DigiKey 2 0.3 0.6 CAP%CER%2200PF%50V%10%%RADIAL Received10 C4,C5,C8 Capacitor 445C8300CND TDK%Corp. DigiKey 3 0.45 1.35 CAP%CER%4.7UF%25V%10%%RADIAL Received11 C2,C3,C9,C11 Capacitor 445C8286CND TDK%Corp. DigiKey 4 0.45 1.8 CAP%CER%10UF%10V%10%%RADIAL Received12 R8,R11 Resistor NA DigiKey UMD%EE%Department 2 0 0 RES%8.2K%OHM%1/8W%1% Received13 R1,R2,R5,R9,R10 Resistor NA DigiKey UMD%EE%Department 5 0 0 RES%10K%OHM%1/8W%1% Received14 R3 Resistor NA DigiKey UMD%EE%Department 1 0 0 RES%12K%OHM%1/8W%1% Received15 R4 Resistor NA DigiKey UMD%EE%Department 1 0 0 RES%330K%OHM%1/8W%1% Received16 R6,R7 Resistor NA DigiKey UMD%EE%Department 2 0 0 RES%1M%OHM%1/8W%1% Received17 FB1 Filter 240C2397C1CND LairdCSignal%Integrity%Products DigiKey 3 0.1 0.3 FERRITE%CHIP%SIGNAL%1000%OHM%SMD Received19 A1 Adapter% 309C1120CND Logical%Systems%Inc. DigiKey 1 5 5 8CPin%Adapter Received20 A2 Adapter% 309C1099CND Logical%Systems%Inc. DigiKey 1 5 5 6CPin%Adapter Received21 A3 Socket%IC%16%Pin% 6100C16WCR DigiKey Radio%Shack 4 2.25 9 16%Pin%Through%Sockets Provided22 B1 Prototype%Board V1042CND DigiKey UMD%EE%Department 1 8.1 8.1 Board Received23 Refector SheetCMetal NA NA Lowes 1 6.99 6.99 Aluminum%Device%Refector Provided24 StandCOffs StandCOffs NA Radio%Shack Radio%Shack 16 0.25 4 Aluminum%StandCOffs Provided25 Battery Battery UB%645 AlTex Eric%Cannif 2 10 20 Sealed%Lead%Batteries Provided26 Box Box NA NA Eric%Cannif 1 0 0 Weather%Restant%Box Provided
Grand%Total 125.43