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Toshiba RF Receiver for Toshiba RF Receiver for HDTVHDTV
Midterm Report 3/3/2005Midterm Report 3/3/2005
Team:Team:
Josue Caballero, Brett DiCio, Josue Caballero, Brett DiCio,
Daniel Hooper, Efosa Ojomo, Daniel Hooper, Efosa Ojomo,
George SewellGeorge Sewell
Background InfoBackground Info
●Sponsor● Aaron Foster
● Engineering Manager● TOSHIBA America Consumer Products, Inc.
● Manufacturing Division in Lebanon
●This plant constructs several of Toshiba's television lines.
● Projection● Flat Screen
Project OverviewProject Overview
• As tvs are finished, the final line is screen tests• Dust flecks• Dead pixels
• Toshiba wants to make test line more efficient
• Previously testing line invovled an individual behind each station hooking/unhooking coax cable
Testing RequirementsTesting Requirements●Test specific channels:
● VHF (30 – 300MHz) & UHF (300-3.0GHz)● Channels 2,2,33,5,,5,66,,77,,99,,1212,,1414,,3636,60,,60,6969
● 55.25,55.25,61.2561.25,77.25,,77.25,83.2583.25,,175.25175.25,,187.25187.25,,205.25205.25, , 471.25471.25,,603.25603.25,747.25,,747.25,801.25801.25 MHz MHz
● CATV● Channels 15 15,,1616,17,,17,2323,,2424,,2525,40,,40,4848,,4949
● 127.25127.25,,133.25133.25,139.25,,139.25,217.25217.25,,223.25223.25,,229.25229.25, , 319.26,319.26,367.25367.25,, 373.25 373.25 MhzMhz
●Have a reliable signal at 40/65/>85 dBHave a reliable signal at 40/65/>85 dBμVμV
Final Test RunFinal Test Run
Current SituationCurrent Situation
• To bring up efficieny, a wireless system was developed• Magnet wire wrapped around plastic• Magnet wire in loop
• Magnet wire is copper that is coated with a thin coat of insulation• Prevents shorting• Better electromagnetic field
Left SideLeft Side
Thought ProcessThought Process
• We began to research and eventually construct some antennas
• Simulated antennas• EZ-NEC
• Tested several antennas• Built replica from coax• Toshiba's magnet (transformer) wire
antenna• Long VHF/UHF antenna from copper
EZ NECEZ NEC
EZ NECEZ NEC
Long VHF/UHF AntennaLong VHF/UHF Antenna
Buying, Building, Testing...Buying, Building, Testing...• Shopped at electronic supply store
• Wire• Shopped at radio shack
• Connectors• Constructed a "Test Station"
• Home Depot• Recieved equipment on temporary
loan from Mr. Foster• Spectrum Analyzer• Pattern Signal Generator
Test Station PlanTest Station Plan
Test StationTest Station
Testing EquipmentTesting Equipment• Agilent E4401B ESA-E Series Spectrum
Analyzer ($8,000)
• Leader NTSC Pattern Generator 408 TACP ($5000)
Testing PatternsTesting Patterns
• Copper replica• X-Y Plane
• 180 Degrees• Consistent
distance• Consistent
frequency
Testing PatternsTesting Patterns
• Factory antenna• X-Y Plane
• 90 Degrees• Y-Z Plane
• 90 Degrees• Consistent
distance• Consistent
frequency
Change In DirectionChange In Direction
• Problems with antenna• Distance shorter than quarter wavelength• Low frequency antennas got huge• No single 750MHz bandwidth antenna
• Most of previous research not needed• RF TRANSFORMERS!
• Prof. Cook & Doc. Watai• Transformer MODEL
Recent EventsRecent Events
• Calculating necessary shape/size of transformer and varying types• Cores• Turns• Diameter
• Bought magnet (transformer) wire• Built crude transformer
• Used 12 guage copper, shielded• Still got good results
Initial Transformer TestingInitial Transformer TestingFrequency vs. Power note:already present VHF air signals boosted test signal
Power dBuVFrequency Mhz 12g Wide/Short 12g Wide/Long 12g Small/Short 12g Small/LongVHF Ch3 – 61.25 57 66 51 52VHF Ch12 – 205.25 65 61 70 56CATV Ch48 – 367.25 63 46 60 63CATV Ch49 – 373.25 59 45 58 62UHF Ch14 – 471.25 50 48 42 60UHF Ch69 – 801.25 57 49 53 47
Distance vs. Power Performed at channel 58 UHF = 735MHzPower dBuV
Distance cm 12g Wide/Short 12g Wide/Long 12g Small/Short 12g Small/Long0 57 52 58 544 52 40 52 428 50 Noise 51 40
12 49 Noise 51 Noise16 47 Noise 50 Noise20 46 Noise 47 Noise
Coming SoonComing Soon
• Finishing calculations• Constructing transformers from
magnet wire• Constructing various types, with
varying cores• Testing• Results