Automated Antenna Controller

Our Team Sam Bryan – Team Leader Electrical Engineer Hardware Prototyping LCD Communication Brandon Gray Electrical Engineer Hardware Prototyping Frequency Counting Jacob Edwards Computer Engineer Microprocessor Programming Ashley Stough Electrical Engineer LCD Communication Frequency Counting Dr. Raymond Winton Academic Advisor Sponsor

Outline IntroductionIntroduction ProblemProblem SolutionSolution System OverviewSystem Overview ConstraintsConstraints –Technical –Practical Special ConcernsSpecial Concerns –Manufacturability –Health and Safety ProgressProgress TimelineTimeline QuestionsQuestions

Introduction What is the automated antenna controller?What is the automated antenna controller? –Digital version of MFJ Enterprises, Inc.’s analog, user-tuned loop antenna controller –Used with MFJ-1786 and MFJ-1788 Super Hi-Q Loop Antennas [1]

Problems with Existing Controller Operation is Time ConsumingOperation is Time Consuming Unit is Difficult to OperateUnit is Difficult to Operate Meter is Difficult to Read AccuratelyMeter is Difficult to Read Accurately [2]

Solution Use microcontroller instead of analog comparison networkUse microcontroller instead of analog comparison network Automate the tuning process to avoid user errorAutomate the tuning process to avoid user error > [3]

Technical Constraints NameConstraint Frequency Frequency must measure and display between 7 and 30MHz ± 30kHz. Standing Wave Ratio A maximum of 3:1 SWR must be achieved. Connector RF connection must be an SO-239 style connector. RF Power Forward and reflected power must be measured and displayed accurately to ± 1W. Power Supply Power supply must be the MFJ-1312D AC adapter.

Practical Constraints CategoryNameDescription Economics Manufacturing Cost Must use parts already used by MFJ. SustainabilityWarranty Must meet MFJ’s 12-months limited warranty. ManufacturabilityDimensions Must be less than 4in x 7in x 7in. Health and Safety Notification Must alert operators when the SWR is at an unsafe level. Health and Safety Safety Must be isolated inside a box to protect user and equipment.

Manufacturability: Size Large enough to accommodate analog and digital displaysLarge enough to accommodate analog and digital displays Within reason from previous modelWithin reason from previous model Suggested Size: 4in x 7in x 7in.Suggested Size: 4in x 7in x 7in. [4]

Health and Safety Enclose the controllerEnclose the controller –Prevent electric shock –Prevent burns from hot components –Prevent RF burns Notify User of unsafe SWRNotify User of unsafe SWR –Alert when SWR > 25 –High SWR could harm transmitter

System Overview

Microcontroller [5] Previous Experience Available from Manufacturer Code Compilation Price PIC 16 0 members Yes Assembly Language $2.97 PIC 18F members Yes C Coding $3.98

Motor Control SupplyCurrentOutputVoltageExperience TI – T314BB H-Bridge High Output Current – 1A 4.5 V- 36V 2 members Switching Circuit LowVCC 0 members

LCD Backlight Supplied by Manufacturer Price WH-1602B- NGB NoYes10.40 WH-1602B- GGE Yes, Green Yes10.40

Timeline MonthAugustSeptemberOctoberNovember Research Hardware Prototyping Programming Testing Operational Prototype

Progress Hardware PrototypingHardware Prototyping ProgrammingProgramming TestingTesting

Hardware Prototyping

Programming [3]

Testing

Testing

Testing

Summary ProblemProblem SolutionSolution System OverviewSystem Overview ConstraintsConstraints –Technical –Practical Special ConcernsSpecial Concerns –Manufacturability –Health and Safety TimelineTimeline ProgressProgress

References [1] FJ-1786.[Online]. Accessed: September 29, [2] 080.pdf [Online]. Accessed: September 27, [3] “PIC18F2420/2520/4420/4520 Datasheet”, Microchip Technology Inc. pg 326. [4]MFJ Enterprises, INC., MFJ Super Hi-Q Loop Antenna: Model MFJ 1786/1788 Instruction Manual, [5] Photos/pic18f2520-i%20sp.JPG. [Online]. Accessed: September 30, 2009.

Questions?