Remote Operated AudioVideo Switcher

1
Remote Operated Audio/Video Switcher
2
Team Members

• Jordan Goulder, Leader
• Joe Laszczak
• Dr. Harden, Advisor

3
Problems With Current A/V Devices

• Low Cost Switchers
• Little crosstalk prevention
• Manually switched
• High-End Receivers
• High cost
• Large size

4
Solution

• Remote Controlled With Current Remote
• Quality Output
• Relatively Small
• Reasonable Price

5
Objectives - Design

• IR Data Format RC5 and RECS 80 from 38-40 kHz
• Signal Loss lt10 dB at 10 MHz
• Min. Input Voltage .667 mV (40 dB)
• Input Frequency 20 Hz to 890 MHz
• Crosstalk 56 dB at 10MHz

6
Objectives - Real World

• Device Size 3in x 4in x 1in
• Cost 60
• Learning Ability User Programmable Remote Button
• Reliability 1 error per 1000 switches
• FCC Compliance FCC Code Part 15

7
User Interface
                                   
 
8
Internal Design
Up
Dn
9
Major Design Issues

• Correctly identifying RECS 80 and RC 5 infrared
  data transmission schemes
• Effectively implement the functionality of the
  switching device through the controller
• Minimize interference while maintaining small
  device dimensions

10
IR Demodulator - Output
11
IR Demodulator - Output
12
IR Reading Algorithm
START
Incoming IR
NO
YES
Wait 400us
Sample
Count
Count lt 14
NO
YES
Wait 1800us
Store IR
END
13
Complex Software Testing
14
Complex Software Test Results
15
Broadcast Signal Info
16
High Frequency RF testing

• Used a high frequency RF generator to generate a
  signals that ranged from 20MHz 890MHz

17
Specification Frequency Test Setup
18
Specification Frequency Testing
19
Hardware Testing
20
Multiplexer PCB
21
Power Consumption
22
Cost of Major Components
23
Specification Checklist

• RC5 Compatablity
• RECS 80 Compatability
• Signal Loss lt 10 db _at_ 10MHz
• Input Frequency Response
• Crosstalk
• Minimum Voltage Response
• Programmable Functionality
• Switching Reliablity
• Cost
• FCC Part 15 Compliancy
• Device Size

• Within Spec
• Within Spec
• Within Spec
• Within Spec
• Within Spec
• Within Spec
• Within Spec
• Within Spec
• Within Spec
• Incomplete
• Incomplete

24
Acknowledgements

• Dr. James Harden, Dr. Joseph Picone
• Dr. J.W. Bruce and graduate staff
• Dr. Donohoe, David Paul

25
Questions?
26
References
References 1 Eugene R. Bartlett, Cable
Television Technology and Operations HDTV and
NTSC Systems, McGraw Hill Publishing Company, New
York, New York, USA, 1990. 2 Wagner
Lipnharski, Infrared, http//www.ustr.net/infrar
ed/infrared1.shtml, UST Research Inc., Orlando,
Florida, November 1999.   3 Gabriel Ricardo,
Michael Vandegriend, Scott Medynski, Infrared
Codes for ConsumerAudio/VideoElectronics, http//
www.ee.ualberta.ca/elliott/ee552/studentAppNotes/
1999f/IR_codes/, University of Alberta, Alberta,
Ontario, Canada, November 1999.   4 Crutchfield
Home Theater Catalog, Crutchfield Home Theater
Catalog, http//www.crutchfield.com/cgi-bin/S-a6A
7XN37AYP/ProdGroup.asp?c4g10420s0 ,
Charlottesville, Virginia, September 2002.   5
Federal Communications Commission, Part 15-
Radio Frequency Devices, http//www.access.gpo.go
v/nara/cfr/waisidx_01/47cfr15_01.html,
Washington, DC, 2001   6 Rheinfelder, William
A, CATV System Engineering Third Edition, Tab
Books, Blue Ridge Summit, PA, USA, 1970.