Project by Santiago Yeomans, Chad Cummins, Gboyega Adeola Guitar Signal Transmitter.

Slides:



Advertisements
Similar presentations
Alternating Current Circuits and Electromagnetic Waves
Advertisements

The L-Network L-networks are used to match the output impedance of one circuit to the input of another. Rsource < Rload, 1< Q < 5 Rsource > Rload, 1
Kit Building Class Lesson 4Page 1 R and X in Series Inductors and capacitors resist the flow of AC. This property is called reactance. Resistance also.
CHAPTER 3: SPECIAL PURPOSE OP-AMP CIRCUITS
Frequency modulation and circuits
Chapter 1 Problems ECET 214 Prof. Park NJIT.
Chelmsford Amateur Radio Society Intermediate Course (4) Transmitters
COMMUNICATION SYSTEM EEEB453 Chapter 3 (III) ANGLE MODULATION
Frequency Characteristics of AC Circuits
Advanced Radio and Radar
LECTURE ON AM/FM TRANSMITTER
Principles of Electronic Communication Systems
Oscillators with LC Feedback Circuits
2/23/ R. Munden - Fairfield University.  Define angle modulation and describe the two categories  Explain a basic capacitor microphone FM generator.
Alternating Current Circuits
Prof. ParkELC 2221 Lecture 1: Introductory Topics Prof. Park ELC 222 Essex County College.
Chapter 3 – Angle Modulation
Principles of Electronic Communication Systems
Chapter 6 FM Circuits.
OSCILLATORS.
General Licensing Class G5A – G5C Electrical Principles Your organization and dates here.
F1 x F2 Sum and Mixing of Frequencies f USB = fc + fm and f LSB = fc − fm eam=EcSin(Wct)+mEc/2Cos(Wc-Wm)t-mEc/2Cos(Wc+Wm)t Carrier LSB USB.
Chapter Two: Radio-Frequency Circuits. Introduction There is a need to modulate a signal using an information signal This signal is referred to as a baseband.
CHAPTER 13 TRANSMITTERS AND RECEIVERS. Frequency Modulation (FM) Receiver.
Electricity, Electronics And Ham Radio “Kopertroniks” By Nick Guydosh 4/12/07.
Alternating-Current Circuits Chapter 22. Section 22.2 AC Circuit Notation.
General Licensing Class G7A – G7C Practical Circuits Your organization and dates here.
Copyright © 2009 Pearson Education, Inc. Chapter 30 Inductance, Electromagnetic Oscillations, and AC Circuits.
Oscillators with LC Feedback Circuits. LC Feedback elements are used for the generation of higher frequencies of oscillation. Because of lower unity gain.
Power Line Communication using an Audio Input
General Licensing Class G8A – G8B Signals and Emissions Your organization and dates here.
Radio Communication SL – Option F.1. Radio communication includes any form of communication that uses radio (EM) waves to transfer information –TV, mobile.
Basic (VHF) Radio Communications
Generation of FM Two methods of FM generation: A. Direct method:
TRANSMITTERS AND RECEIVERS
Unit-3 Tuned Amplifiers
TRANSISTOR TUNED AMPLIFIERS. Inroduction  Sometimes it is desired that an amplifier should amplify either a single frequency or a narrow band of frequencies.
COMMUNICATION SYSTEM EEEB453 Chapter 2 AMPLITUDE MODULATION Dept of Electrical Engineering Universiti Tenaga Nasional.
CommunicationElectronics Principles & Applications Third Edition Chapter 6 Radio Transmitters ©2001 Glencoe/McGraw-Hill Louis E. Frenzel.
McGraw-Hill © 2008 The McGraw-Hill Companies, Inc. All rights reserved. Principles of Electronic Communication Systems FM Circuits.
Copyright © 2009 Pearson Education, Inc. Chapter 33 Inductance, Electromagnetic Oscillations, and AC Circuits Part II.
Technician License Course Chapter 2 Radio and Electronics Fundamentals
Amplitude Modulated Radio Frequency Transmission System Instructor: Dr. Fu By: Megan Myles, David Jackson, and Edwin Wambwa.
Electrical Principles 1 1 G5 - ELECTRICAL PRINCIPLES [3 exam questions - 3 groups] G5A - Reactance; inductance; capacitance; impedance; impedance matching.
Chapter 5 – Oscillators – Part 2
Meghe Group of Institutions Department for Technology Enhanced Learning 1.
FM TRANSMITTER Punjab Edusat Society. FM TRANSMITTERS Frequency modulation technique is used. In FM frequency of the carrier is varied in proportion with.
FM RECEIVER AND DETECTION
Government Engineering College, Godhra SUBJECT : Audio and Video System GEC GODHRA.
Radio Frequency Osc.. 2- RADIO-FREQUENCY OSCILLATORS Radio-frequency (RF) oscillators must satisfy the same basic criteria for oscillation as was discussed.
Crystal Oscillator Circuit and Its Working
Transformers and Impedance. Review Two types of current: –ac –dc Two fundamental principles: –Moving electrons create magnetic fields –Moving or changing.
1 Transmitters A transmitter must generate a signal with the right type of modulation, with sufficient power, at the right carrier frequency, and with.
Principles of Electronic Communication Systems. Chapter 6 FM Circuits.
Radio Communication SL/HL – Option F.1. Radio communication includes any form of communication that uses radio (EM) waves to transfer information –TV,
Hartley Oscillator Circuit Theory Working and Application
(4) Filters.
Inductance, Electromagnetic Oscillations, and AC Circuits
The Zener Diode The zener diode exhibits a constant voltage
Oscillators with LC Feedback Circuits
Generation & Detection of FM Application of FM
PART 3:GENERATION AND DETECTION OF ANGLE MODULATION
ME3000 ANALOG ELECTRONICS [Slide 13] Oscillators BY DREAMCATCHER
Amateur Extra Q & A Study Pool
General Licensing Class
Passive Bandpass and Notch Filters
Amateur Extra Q & A Study Pool
TRANSMITTERS AND RECEIVERS
The Zener Diode The zener diode exhibits a constant voltage
Chapter 5 – Oscillators – Part 2
Presentation transcript:

Project by Santiago Yeomans, Chad Cummins, Gboyega Adeola Guitar Signal Transmitter

Introduction Electric guitar output will connect to FM transmitter Transmitted audio will be received at receiver and connected to guitar amplifier ¼ “ audio plugs used for connections –output of guitar to transmitter –output of receiver to amp

Frequency Modulation vs. Phase Modulation FMPM Fair S/N ratioBest S/N ratio Variable modulation index Constant modulation index Easier implementation Phase lock loop to demodulate signal VCO can produce high index freq. modulation Multipliers needed to produce high index PM Cost efficientExpensive

Flow Diagram Reactance Modulator Carrier Oscillator Buffer Amplifier Frequency Multipliers Driver Amplifier Power output amplifier Reactance Modulator: The nature of FM is that when the baseband signal is zero, the carrier is at its “ carrier ” frequency, when it peaks the carrier deviation is at a maximum and when it troughs the deviation is at its minimum. This deviation is simply a quickening or slowing down of frequency around the carrier frequency by an amount proportional to the baseband signal. In order to convey this characteristic of FM on the carrier wave, the capacitance must be varied. Buffer Amplifier: The buffer amplifier acts as a high input impedance with a low gain and low output impedance associated with it. The high input impedance prevents loading effects from the oscillator section. Frequency Multipliers: To avoid frequency drifts of the LC tank while modulating the carrier by the baseband with a high modulation index, modulation can take place at lower frequencies with a higher Q factor of the oscillator. Power Output Section- Develops the final carrier power to be transmitted. Also included here is an impedance matching network, in which the output impedance is the same as that on the load (antenna)

Block Diagram In Out

Three Stages Signal Source (Guitar, CD player) –CD Audio Output: >1.5 V –Guitar Signal Output: 150mv –Output Impedance: Transmitter –Colpitts Oscillator ---  –Circuit Self-Amplification Receiver –Hartley Oscillator ---  –Audio amplifier

Oscillator Resonant Circuits. Resonant frequency is that at which the impedance of capacitor & inductor is the same; it represents the oscillator carrier frequency in Hertz. The parallel resonant circuit we used, known as an LC tank, takes the advantage of the resonant frequency and allows the impedance to be at a maximum & the current at a minimum at Fc. Q : ratio of maximum energy stored to the amount lost per ac cycle. It determines the 3dB bandwidth of resonant circuits. Since we didn ’ t have a resistor in the LC tank, the inherent properties of inductor & capacitor at high frequencies had to be taken into account.

Essential Circuit Elements Transistors: –Transmitter: 2 (2N3904) –Receiver: BF256, 2N3904 Inductors –Copper Coils 5 turns 16 turns

Transmitter

Receiver

LPF 682 Hz 1 kHz Chebyshev Filters 6-Band Equalization Stage

2 kHz 4 kHz

8 kHz 10.9 kHz

Pspice Simulation

Output of receiver connected to guitar amplifier

Project Achievements Achieved both FM RF Transmission and reception –Carrier frequency of 100 MHz Audio received and sent to guitar amplifier Audio from cd player worked well Temporarily had guitar audio transmitting and receiving Circuits were low cost to build

Performance Quality of Audio –Clear at times, some noise occasionally Transmission –Better transmission was achieved with a source device having a larger input impedance.

Project Challenges Setup both transmitter and receiver for same carrier frequency (100MHz) –Variable Capacitor range was unknown, not sure about the pins (Variable cap taken from $5 handheld radio bought from Wal-Mart)

Challenges continued Working with the LM741 Op Amp Working with a breadboard Parasitic Capacitances Unable to Effectively Simulate Inductors Parasitic Capacitances inherent in high frequency engineering

Oversights Impedance Mismatching –Between Amplifier and Receiver Under-estimated difficulty of amplifying guitar audio before transmission

Timeline

Factors for obtaining better S/N Resistive properties in LC tank A) Skin effect - at high frequencies, there is less cross sectional area for carriers to move, so the resistance increase; when the magnetic field at the centre of the wire increases and local inductive reactance takes over, that is, stray capacitances begin to build up between adjacent turns. B) Dielectric permittivity Temperature Stability of the oscillator Components in oscillator have non-zero temperature coefficients. To find the change in frequency for a given temperature change, simply multiply the coefficient by the temperature change & the centre frequency. Major source of frequency instability: Capacitor & Transistor (junction capacitance) More compact circuitry Wrapping the circuit with aluminum foil to electromagnetically shield the RF stage. Unwanted electromagentic radiation had to be stopped from destructively interfering With the carrier modulation.

Future Improvements Replace the common 2N3904 transistor with a BC549 which would perform better with high frequency Use a ground plane for better performance of sensitive circuits Solder all connections