02/12/03 brian crosby electrical report auto tuner brian crosby
Post on 22-Dec-2015
215 views
TRANSCRIPT
02/12/03 Brian CrosbyElectrical Report
Auto Tuner
Brian CrosbyBrian Crosby
02/12/03 Brian CrosbyElectrical Report
Background
Manual Tuning a String Instrument Manual Tuning a String Instrument to Reference Tones Takes Skill, to Reference Tones Takes Skill, and Is Often a Time Consuming and Is Often a Time Consuming
and Error-prone Process.and Error-prone Process.
02/12/03 Brian CrosbyElectrical Report
Problem
Develop a Hand Held System Develop a Hand Held System That Automatically Tunes a String That Automatically Tunes a String Instrument to Its Standard Tuning Instrument to Its Standard Tuning
Quickly and Effectively.Quickly and Effectively.
02/12/03 Brian CrosbyElectrical Report
Solution Microphone to listenMicrophone to listen Filter to clean signalFilter to clean signal Comparator to convert signalComparator to convert signal Micro-controller to decideMicro-controller to decide Gear motor to correct and adjustGear motor to correct and adjust
02/12/03 Brian CrosbyElectrical Report
System Overview
Microphone
FilterComparator
Gear
Motor
Instrument is plucked
High
Low
Micro Controller
02/12/03 Brian CrosbyElectrical Report
What it looks Like
ON / Off
Six position Switch
Mode Selection
LCD Display
Tuning peg Heads
02/12/03 Brian CrosbyElectrical Report
Auto Tuners Electrical Layout
02/12/03 Brian CrosbyElectrical Report
Electrical Overview
LOW PASS
FILTER
PIC
COMPARATOR
H BRIDGE MOTOR DRIVER
GEAR MOTOR
INPUT ¼”
JACK
On/OFF BUTTON
MODE BUTTONBATTERY
DISPLAY
SIX POSITION SWITCHCircuit Board
02/12/03 Brian CrosbyElectrical Report
Input Filter
Guitar freq. Ranges.Guitar freq. Ranges. 330hz to 1.3khz.330hz to 1.3khz.
Low passed freq.Low passed freq. R=1k, C=.05uf.R=1k, C=.05uf. Filters off Filters off
frequencies frequencies above 2 kHz.above 2 kHz.
02/12/03 Brian CrosbyElectrical Report
Comparator forfirst 4 strings
Voltage divider set comparator reference
voltage to 100mv.
02/12/03 Brian CrosbyElectrical Report
Comparator for last two strings
Parallel combination of resistors lowers
comparator reference to 75mv
02/12/03 Brian CrosbyElectrical Report
0 to 4.5 Volt Square Wave
02/12/03 Brian CrosbyElectrical Report
Micro-Controller 16f628 Pic16f628 Pic Voltage rangeVoltage range
3.0V to 5.5v3.0V to 5.5v Power consumptionPower consumption
2.0ma @ 5.0v2.0ma @ 5.0v
15ua @3.0v15ua @3.0v
02/12/03 Brian CrosbyElectrical Report
H Bridged Motor Driver
02/12/03 Brian CrosbyElectrical Report
Six Position Switch
Power in From Micro Controller
Divided voltage Sent back to Micro
Controller
02/12/03 Brian CrosbyElectrical Report
3 AA Alkaline 4.5V
02/12/03 Brian CrosbyElectrical Report
Auto Tuner Schematic
16F628
02/12/03 Brian CrosbyElectrical Report
For More Information
Visit the Auto Tuner Web PageVisit the Auto Tuner Web Page
www.Vtc.edu/elm/projects/2002-www.Vtc.edu/elm/projects/2002-2003/AutoTuner/WebPage2003/AutoTuner/WebPage
02/12/03 Brian CrosbyElectrical Report
Any Questions ???