Fall 2006P7305: Freshman Practicum AM Receiver P7305: Learning Module for EE Freshman Practicum Chris Urban: Lead Engineer Hans-Christian Rotmann: Project Manager Sponsor: Dr. Robert Bowman

Fall 2006P7305: Freshman Practicum AM Receiver Project Description A 2 week hands-on module for EE Freshman Practicum class. Students will simulate and prototype a functional AM receiver. After testing and debugging, the receiver will be constructed in a printed circuit board (provided) for the student to keep.

Fall 2006P7305: Freshman Practicum AM Receiver Philosophical Course Objectives Excite Students about EE Through Hands-on Learning and Studio Style Teaching. Bring Engineering Relevance to Physics and Calculus. Reinforce Experiential Learning – Explore. Promote Mentoring of Freshmen by Faculty and Upper Division Students. Connect Students with Their Faculty Advisors. Improve Early, Career Decision-making.

Fall 2006P7305: Freshman Practicum AM Receiver The Path Forward For Freshman Practicum Course content in some areas has been challenging for students and some faculty. Students enjoy hands-on experience and would like more time to tinker with electronics. Some of the lab exercises are considered too structured such as the modules for MATLAB and C Programming.

Fall 2006P7305: Freshman Practicum AM Receiver Project Objectives Provide freshman students with the circuit construction and debugging skills that are required later in their studies. Introduce the Use of Software Tools Used Throughout the BSEE Program –PSpice (Circuit Simulation) –Software to Transfer Instrument Data to a Computer Enable students to have hands-on exposure to a wide range of areas within the field –Communications, EM fields, analog electronics.

Fall 2006P7305: Freshman Practicum AM Receiver Learning Style “Learn By Doing” “Just-in-Time and Just-Enough Theory” “Divide and Conquer” a REAL CIRCUIT

Fall 2006P7305: Freshman Practicum AM Receiver Main project requirements Hands-on focus. No background in EE required: –Easy to debug. –Low component count. –Clearly identifiable functional blocks within circuit schematics. Highly reliable and robust: –Resistant to component variations and circuit assembly skills. 6 hour time limit for entire project (theory, simulation, prototyping, final assembly).

Fall 2006P7305: Freshman Practicum AM Receiver Main project requirements Parts procurement considerations: –Low cost (< US$5.00) –Widely available replacements. Fully documented outline of the lab procedures –Serves as basis for the updated Freshman Practicum textbook. –Includes test plan, simulation files and results, and diagrams of expected waveforms.

Fall 2006P7305: Freshman Practicum AM Receiver Design Concept Audible Output Modulated Radio Signal Antenna Tuning Network Peak Detector Amplifier Output Jack Functions: Receives the modulated signal Tunes to a particular frequency Detects the original signal Amplifies the signal to an acceptable level Signal sent to a set of headphones

Fall 2006P7305: Freshman Practicum AM Receiver Technical Risk Assessment Component reliability and non-idealities –Change in tuning frequency range may be outside AM band. Output volume –Weak signal strength may not produce suitable output amplitude. Antenna size –Minimum antenna length may be in the order of 100 ft.

Fall 2006P7305: Freshman Practicum AM Receiver Technical Risk Assessment Proposed solutions: –Use component values that are above the non-idealities associated with the prototype board. –Prototype results suggest that a 10ft antenna is suitable for radio stations in close proximity. The antenna may be replaced with ferrite-core coil, which provides better selectivity and reception. This relates directly to circuit reliability requirements.

Fall 2006P7305: Freshman Practicum AM Receiver Current Project State Initial prototype exhibited excellent reception and signal quality for WHAM (1180 KHz). Other stations did not produce suitable output. Prototype works with voltage supply currently available in the Freshman Practicum parts kit. –Estimated battery life between 120 and 160 hours. On target for cost of goods < US$ 5.00 (US$ 2.82). –This allows for the purchasing of alternative antennas and tuning elements.

Fall 2006P7305: Freshman Practicum AM Receiver SD2 Project Schedule Outline Dec 15 th :Finalize prototype design (including considerations for alternate parts). Dec 22 nd :First PCB prototype. Jan 12 th :Custom PCB design, incorporating test points. Jan 26 th :Test complete module with freshman students. Feb 2 nd :Design review and demonstration. Feb 16 th :Completion of all required documentation and supplementary materials. Feb 23 rd :Final project review.