Project Synopsis

5/26/2018 Project Synopsis

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ABSTRACT

GSM based Irrigation Water Pump Controller forIlliterates

The aim of this project is to provide an efficientsolution for automatic control ofirrigation motor for illiterates. Now a daystechnology is running with time, itcompletely occupied the life style of human beings.Even though there is such animportance for technology in our routine life there

are even people whose life styles arevery far to this well known term technology. So it isour responsibility to design fewreliable systems which can be even efficiently usedby them. This basic idea gave birth tothe project DTMF controlled soil moisture sensor.Here the automation process is donethrough the micro controller based technology.


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INTRODUCTION

.

In our project we make use of one microcontroller, which is dedicated at the water

pump. The microcontroller forms the heart of the device. A relay switch to whichirrigation motor is connected which is operated through microcontroller.To operate the system initially we should make a call to the mobile phone whichis present at the soil moisture sensor in the fields. That mobile phone will beautomatically will be answered after one or two rings then the control of the sensor is inour hands by using keypad buttons of our mobile phone the motor will be ON/OFFthrough Relay switch.The design of this system is very much sensitive and should be handled withutmost care because the microcontroller is a 5 volts device and it is employed tomonitorthe house hold power consumption per day where it should be interfaced with a 240

voltsenergy meter. So every small parameter should be given high importance whiledesigningthe interfacing circuit between the controller and the water motor.


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BLOCK DIAGRAM


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DESCRIPTION

This project provides exposure to the following

technologies:

1. Microcontroller.2. Embedded C programming for

microcontroller.

3. DTMF decoder.

4. Design of PCB.

The major building blocks of this project are:1. Regulated Power Supply.

2. Microcontroller.

3. DTMF decoder.

4. Relay with driver (Interfacing circuit).

5. Crystal oscillator.6. Reset.

7. LED indicators.


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Softwares used:

1. PIC-C compiler for Embedded C

programming.

2. PIC kit programmer for dumping code

into Micro controller.

3. Express SCH for Circuit design.

4. Proteus for hardware simulation.


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FEATURES

1. Controls high voltage water pumps.

2. Feedback generated with the help of LEDindicator.3. Highly sensitive.4. Power saving.5. Low cost.6. Remote control from anywhere in the world.

APPLICATION

1. Utilized for irrigation purpose.2. Very useful for illiterates operation.3. Can be operated from any place in the world.

4. No need of manual check for moisture level insoil.


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Regulated Power Supply:


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Dual-tone multi-frequency signaling

From Wikipedia, the free encyclopedia

Jump to:navigation,search"Tone dialing" redirects here. For Ornette Coleman album, seeTone Dialing (album).

This article needs additional citations forverification.Please helpimprove this articlebyadding citations to reliable sources.Unsourced material may be challenged and

removed. (November 2009)

One of the few production telephone DTMF keypads with all 16 keys, from anAutovon

Telephone. The column of red keys produces the A, B, C, and D DTMF events.

Dual-tone multi-frequency signaling(DTMF) is used fortelecommunication signalingover

analog telephone lines in the voice-frequency band betweentelephonehandsets and othercommunications devices and theswitching center.The version of DTMF that is used inpush-button telephonesfor tone dialing is known as Touch-Tone. It was developed byWestern

Electricand first used by theBell Systemin commerce, using that name as a registered

trademark. DTMF is standardized byITU-TRecommendationQ.23.It is also known in the UKasMF4.

Othermulti-frequencysystems are used for internal signaling within the telephone network.

Introduced by AT&T in 1963,[1]

the Touch-Tone system using thetelephone keypadgradually

replaced the use ofrotary dialand has become the industry standard forlandlineservice.

Contents

1 Multifrequency signaling

2 #, *, A, B, C, and D

3 Keypad

4 Special tone frequencies

5 See also
http://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#mw-navigationhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#mw-navigationhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#mw-navigationhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#p-searchhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#p-searchhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#p-searchhttp://en.wikipedia.org/wiki/Tone_Dialing_%28album%29http://en.wikipedia.org/wiki/Tone_Dialing_%28album%29http://en.wikipedia.org/wiki/Tone_Dialing_%28album%29http://en.wikipedia.org/wiki/Wikipedia:Verifiabilityhttp://en.wikipedia.org/wiki/Wikipedia:Verifiabilityhttp://en.wikipedia.org/wiki/Wikipedia:Verifiabilityhttp://en.wikipedia.org/w/index.php?title=Dual-tone_multi-frequency_signaling&action=edithttp://en.wikipedia.org/w/index.php?title=Dual-tone_multi-frequency_signaling&action=edithttp://en.wikipedia.org/w/index.php?title=Dual-tone_multi-frequency_signaling&action=edithttp://en.wikipedia.org/wiki/Help:Introduction_to_referencing/1http://en.wikipedia.org/wiki/Help:Introduction_to_referencing/1http://en.wikipedia.org/wiki/Help:Introduction_to_referencing/1http://en.wikipedia.org/wiki/Autovonhttp://en.wikipedia.org/wiki/Autovonhttp://en.wikipedia.org/wiki/Autovonhttp://en.wikipedia.org/wiki/Signalling_%28telecommunications%29http://en.wikipedia.org/wiki/Signalling_%28telecommunications%29http://en.wikipedia.org/wiki/Signalling_%28telecommunications%29http://en.wikipedia.org/wiki/Telephonehttp://en.wikipedia.org/wiki/Telephonehttp://en.wikipedia.org/wiki/Telephonehttp://en.wikipedia.org/wiki/Automatic_telephone_exchangehttp://en.wikipedia.org/wiki/Automatic_telephone_exchangehttp://en.wikipedia.org/wiki/Automatic_telephone_exchangehttp://en.wikipedia.org/wiki/Push-button_telephonehttp://en.wikipedia.org/wiki/Push-button_telephonehttp://en.wikipedia.org/wiki/Push-button_telephonehttp://en.wikipedia.org/wiki/Push-button_telephonehttp://en.wikipedia.org/wiki/Western_Electrichttp://en.wikipedia.org/wiki/Western_Electrichttp://en.wikipedia.org/wiki/Western_Electrichttp://en.wikipedia.org/wiki/Western_Electrichttp://en.wikipedia.org/wiki/Bell_Systemhttp://en.wikipedia.org/wiki/Bell_Systemhttp://en.wikipedia.org/wiki/Bell_Systemhttp://en.wikipedia.org/wiki/ITU-Thttp://en.wikipedia.org/wiki/ITU-Thttp://en.wikipedia.org/wiki/ITU-Thttp://www.itu.int/rec/T-REC-Q.23/enhttp://www.itu.int/rec/T-REC-Q.23/enhttp://www.itu.int/rec/T-REC-Q.23/enhttp://en.wikipedia.org/wiki/Multi-frequencyhttp://en.wikipedia.org/wiki/Multi-frequencyhttp://en.wikipedia.org/wiki/Multi-frequencyhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#cite_note-1http://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#cite_note-1http://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#cite_note-1http://en.wikipedia.org/wiki/Telephone_keypadhttp://en.wikipedia.org/wiki/Telephone_keypadhttp://en.wikipedia.org/wiki/Telephone_keypadhttp://en.wikipedia.org/wiki/Rotary_dialhttp://en.wikipedia.org/wiki/Rotary_dialhttp://en.wikipedia.org/wiki/Rotary_dialhttp://en.wikipedia.org/wiki/Landlinehttp://en.wikipedia.org/wiki/Landlinehttp://en.wikipedia.org/wiki/Landlinehttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Multifrequency_signalinghttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Multifrequency_signalinghttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#.23.2C_.2A.2C_A.2C_B.2C_C.2C_and_Dhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#.23.2C_.2A.2C_A.2C_B.2C_C.2C_and_Dhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Keypadhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Keypadhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Special_tone_frequencieshttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Special_tone_frequencieshttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#See_alsohttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#See_alsohttp://en.wikipedia.org/wiki/File:66a3aDTMFpad.jpghttp://en.wikipedia.org/wiki/File:66a3aDTMFpad.jpghttp://en.wikipedia.org/wiki/File:66a3aDTMFpad.jpghttp://en.wikipedia.org/wiki/File:66a3aDTMFpad.jpghttp://en.wikipedia.org/wiki/File:66a3aDTMFpad.jpghttp://en.wikipedia.org/wiki/File:66a3aDTMFpad.jpghttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#See_alsohttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Special_tone_frequencieshttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Keypadhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#.23.2C_.2A.2C_A.2C_B.2C_C.2C_and_Dhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Multifrequency_signalinghttp://en.wikipedia.org/wiki/Landlinehttp://en.wikipedia.org/wiki/Rotary_dialhttp://en.wikipedia.org/wiki/Telephone_keypadhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#cite_note-1http://en.wikipedia.org/wiki/Multi-frequencyhttp://www.itu.int/rec/T-REC-Q.23/enhttp://en.wikipedia.org/wiki/ITU-Thttp://en.wikipedia.org/wiki/Bell_Systemhttp://en.wikipedia.org/wiki/Western_Electrichttp://en.wikipedia.org/wiki/Western_Electrichttp://en.wikipedia.org/wiki/Push-button_telephonehttp://en.wikipedia.org/wiki/Push-button_telephonehttp://en.wikipedia.org/wiki/Automatic_telephone_exchangehttp://en.wikipedia.org/wiki/Telephonehttp://en.wikipedia.org/wiki/Signalling_%28telecommunications%29http://en.wikipedia.org/wiki/Autovonhttp://en.wikipedia.org/wiki/Help:Introduction_to_referencing/1http://en.wikipedia.org/w/index.php?title=Dual-tone_multi-frequency_signaling&action=edithttp://en.wikipedia.org/wiki/Wikipedia:Verifiabilityhttp://en.wikipedia.org/wiki/Tone_Dialing_%28album%29http://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#p-searchhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#mw-navigation


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6 References

7 Further reading

8 External links

Multifrequency signaling

Prior to the development of DTMF, numbers were dialed on automated telephone systems by

means ofpulse dialing(dial pulse,DP, in theU.S.)or loop disconnect (LD) signaling, which

functions by rapidly disconnecting and re-connecting thecalling party's telephone line, similar to

flicking a light switch on and off. The repeated interruptions of the line, as thedialspins, soundslike a series of clicks. The exchange equipment interprets these dial pulses to determine the

dialed number. Loop disconnect range was restricted by telegraphic distortion and other

technical problems,[which?]

and placing calls over longer distances required either operator

assistance (operators used an earlier kind ofmulti-frequencydial) or the provision ofsubscribertrunk dialingequipment.

Other vendors of compatible telephone equipment called the Touch-Tone feature Tone dialingorDTMF, or used their own registered trade names such as the Digitoneof Northern Electric (now

known asNortel Networks).

The DTMF system uses eight different frequency signals transmitted in pairs to represent 16

different numbers, symbols and letters - as detailed below.

As a method ofin-band signaling,DTMF tones were also used bycable televisionbroadcasters

to indicate the start and stop times of local commercial insertion points during station breaks for

the benefit of cable companies. Until betterout-of-band signalingequipment was developed inthe 1990s, fast, unacknowledged, and loud DTMF tone sequences could be heard during the

commercial breaks of cable channels in the United States and elsewhere.[citation needed]

Multi-frequency signaling(see alsoMF)is a group of signaling methods that use a mixture of

twopure tone(puresine wave)sounds. Various MF signalingprotocolswere devised by theBell

SystemandCCITT.The earliest of these were forin-bandsignaling between switching centers,wherelong-distancetelephone operatorsused a 16-digitkeypadto input the next portion of the

destination telephone number in order to contact the next downstream long-distance telephone

operator. This semi-automated signaling and switching proved successful in both speed and costeffectiveness. Based on this prior success with using MF by specialists to establish long-distance

telephone calls,Dual-tone multi-frequency (DTMF) signaling was developed for theconsumerto

signal their own telephone-call's destination telephone number instead of talking to a telephone

operator.

AT&Ts Compatibility Bulletin No. 105 described the product as "a method for pushbutton

signaling from customer stations using the voice transmission path." In order to preventconsumer telephones from interfering with the MF-based routing and switching between

telephone switching centers, DTMF's frequencies differ from all of the pre-existing MF signaling

protocols between switching centers: MF/R1,R2,CCS4, CCS5, and others that were laterreplaced bySS7digital signaling. DTMF, as used inpush-button telephonetone dialing, was
http://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Referenceshttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Referenceshttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Further_readinghttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Further_readinghttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#External_linkshttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#External_linkshttp://en.wikipedia.org/wiki/Pulse_dialinghttp://en.wikipedia.org/wiki/Pulse_dialinghttp://en.wikipedia.org/wiki/Pulse_dialinghttp://en.wikipedia.org/wiki/United_Stateshttp://en.wikipedia.org/wiki/United_Stateshttp://en.wikipedia.org/wiki/United_Stateshttp://en.wikipedia.org/wiki/Calling_partyhttp://en.wikipedia.org/wiki/Calling_partyhttp://en.wikipedia.org/wiki/Calling_partyhttp://en.wikipedia.org/wiki/Rotary_dialhttp://en.wikipedia.org/wiki/Rotary_dialhttp://en.wikipedia.org/wiki/Rotary_dialhttp://en.wikipedia.org/wiki/Wikipedia:Avoid_weasel_wordshttp://en.wikipedia.org/wiki/Wikipedia:Avoid_weasel_wordshttp://en.wikipedia.org/wiki/Wikipedia:Avoid_weasel_wordshttp://en.wikipedia.org/wiki/Multi-frequencyhttp://en.wikipedia.org/wiki/Multi-frequencyhttp://en.wikipedia.org/wiki/Multi-frequencyhttp://en.wikipedia.org/wiki/Subscriber_trunk_dialinghttp://en.wikipedia.org/wiki/Subscriber_trunk_dialinghttp://en.wikipedia.org/wiki/Subscriber_trunk_dialinghttp://en.wikipedia.org/wiki/Subscriber_trunk_dialinghttp://en.wikipedia.org/wiki/Nortel_Networkshttp://en.wikipedia.org/wiki/Nortel_Networkshttp://en.wikipedia.org/wiki/Nortel_Networkshttp://en.wikipedia.org/wiki/In-band_signalinghttp://en.wikipedia.org/wiki/In-band_signalinghttp://en.wikipedia.org/wiki/In-band_signalinghttp://en.wikipedia.org/wiki/Cable_televisionhttp://en.wikipedia.org/wiki/Cable_televisionhttp://en.wikipedia.org/wiki/Broadcastinghttp://en.wikipedia.org/wiki/Broadcastinghttp://en.wikipedia.org/wiki/Broadcastinghttp://en.wikipedia.org/wiki/Out-of-band_signalinghttp://en.wikipedia.org/wiki/Out-of-band_signalinghttp://en.wikipedia.org/wiki/Out-of-band_signalinghttp://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttp://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttp://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttp://en.wikipedia.org/wiki/R2_signallinghttp://en.wikipedia.org/wiki/R2_signallinghttp://en.wikipedia.org/wiki/R2_signallinghttp://en.wikipedia.org/wiki/Pure_tonehttp://en.wikipedia.org/wiki/Pure_tonehttp://en.wikipedia.org/wiki/Pure_tonehttp://en.wikipedia.org/wiki/Sine_wavehttp://en.wikipedia.org/wiki/Sine_wavehttp://en.wikipedia.org/wiki/Sine_wavehttp://en.wikipedia.org/wiki/Communications_protocolhttp://en.wikipedia.org/wiki/Communications_protocolhttp://en.wikipedia.org/wiki/Communications_protocolhttp://en.wikipedia.org/wiki/Bell_Systemhttp://en.wikipedia.org/wiki/Bell_Systemhttp://en.wikipedia.org/wiki/Bell_Systemhttp://en.wikipedia.org/wiki/Bell_Systemhttp://en.wikipedia.org/wiki/CCITThttp://en.wikipedia.org/wiki/CCITThttp://en.wikipedia.org/wiki/CCITThttp://en.wikipedia.org/wiki/In-bandhttp://en.wikipedia.org/wiki/In-bandhttp://en.wikipedia.org/wiki/In-bandhttp://en.wikipedia.org/wiki/Long_distance_callinghttp://en.wikipedia.org/wiki/Long_distance_callinghttp://en.wikipedia.org/wiki/Switchboard_operatorhttp://en.wikipedia.org/wiki/Switchboard_operatorhttp://en.wikipedia.org/wiki/Switchboard_operatorhttp://en.wikipedia.org/wiki/Numerical_digithttp://en.wikipedia.org/wiki/Numerical_digithttp://en.wikipedia.org/wiki/Keypadhttp://en.wikipedia.org/wiki/Keypadhttp://en.wikipedia.org/wiki/Keypadhttp://en.wikipedia.org/wiki/Telephone_callhttp://en.wikipedia.org/wiki/Telephone_callhttp://en.wikipedia.org/wiki/Consumerhttp://en.wikipedia.org/wiki/Consumerhttp://en.wikipedia.org/wiki/Consumerhttp://en.wikipedia.org/wiki/R2_signallinghttp://en.wikipedia.org/wiki/R2_signallinghttp://en.wikipedia.org/wiki/R2_signallinghttp://en.wikipedia.org/wiki/Signalling_System_No_7http://en.wikipedia.org/wiki/Signalling_System_No_7http://en.wikipedia.org/wiki/Signalling_System_No_7http://en.wikipedia.org/wiki/Push-button_telephonehttp://en.wikipedia.org/wiki/Push-button_telephonehttp://en.wikipedia.org/wiki/Push-button_telephonehttp://en.wikipedia.org/wiki/Push-button_telephonehttp://en.wikipedia.org/wiki/Signalling_System_No_7http://en.wikipedia.org/wiki/R2_signallinghttp://en.wikipedia.org/wiki/Consumerhttp://en.wikipedia.org/wiki/Telephone_callhttp://en.wikipedia.org/wiki/Keypadhttp://en.wikipedia.org/wiki/Numerical_digithttp://en.wikipedia.org/wiki/Switchboard_operatorhttp://en.wikipedia.org/wiki/Long_distance_callinghttp://en.wikipedia.org/wiki/In-bandhttp://en.wikipedia.org/wiki/CCITThttp://en.wikipedia.org/wiki/Bell_Systemhttp://en.wikipedia.org/wiki/Bell_Systemhttp://en.wikipedia.org/wiki/Communications_protocolhttp://en.wikipedia.org/wiki/Sine_wavehttp://en.wikipedia.org/wiki/Pure_tonehttp://en.wikipedia.org/wiki/R2_signallinghttp://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttp://en.wikipedia.org/wiki/Out-of-band_signalinghttp://en.wikipedia.org/wiki/Broadcastinghttp://en.wikipedia.org/wiki/Cable_televisionhttp://en.wikipedia.org/wiki/In-band_signalinghttp://en.wikipedia.org/wiki/Nortel_Networkshttp://en.wikipedia.org/wiki/Subscriber_trunk_dialinghttp://en.wikipedia.org/wiki/Subscriber_trunk_dialinghttp://en.wikipedia.org/wiki/Multi-frequencyhttp://en.wikipedia.org/wiki/Wikipedia:Avoid_weasel_wordshttp://en.wikipedia.org/wiki/Rotary_dialhttp://en.wikipedia.org/wiki/Calling_partyhttp://en.wikipedia.org/wiki/United_Stateshttp://en.wikipedia.org/wiki/Pulse_dialinghttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#External_linkshttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#Further_readinghttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#References


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known throughout the Bell System by the trademark Touch-Tone. This term was first used by

AT&T in commerce on July 5, 1960 and then was introduced to the public on November 18,

1963, when the firstpush-button telephonewas made available to the public. It was AT&T'sregistered trademark from September 4, 1962 to March 13, 1984, and is standardized byITU-T

RecommendationQ.23.It is also known in the UK as MF4.

In telephony, multi-frequency signaling (MF) is a signaling system that was introduced by the

Bell System after WWII. It uses a combination of tones for address (phone number) and

supervision signaling. The signaling is sent in-band over the same channel as the bearer channelused for voice traffic.

Multi-frequency signaling is a precursor of modern DTMF signaling (TouchTone), now used forsubscriber signalling. DTMF uses eight frequencies.

Operation: Digits are represented by two simultaneous tones selected from a sets of five (MF2/5), six (MF 2/6), or eight (MF 2/8) frequencies. The frequency combinations are played, one at

a time for each digit, to the remote multi-frequency receiver in a distant telephone exchange. MFwas used for signaling in trunking applications.

Using MF signaling, the originating telephone switching office sends a starting signal such as a

seizure (off-hook) by toggling the AB bits. After the initial seizure, the terminating officeacknowledges a ready state by responding with a wink (short duration seizure) and then goesback on-hook (wink start). The originating office sends the destination digits to the terminating

switch.

MF signalling tones were vulnerable to being spoofed using blue boxes which generated a 2600

hertz tone to disconnect a toll call in progress and provided an operator-style MF keypad to dial

another call using the same trunk.

MF and other in-band signaling systems differ from Signaling System 7 (SS7) in that the routingdigits are out-pulsed in MF format in the same voiceband channel used for voice. The dialing

user cannot detect these digits being out-pulsed because the audio connection is not established

all the way to the users handset or device until after the connection is established with the

terminating switch. Following a full connection, the same audio channel is connected to the userin order to communicate the voice, modem or fax data across that same 64-kbit channel

previously used for the in-band MF signaling.

#, *, A, B, C, and D
http://en.wikipedia.org/wiki/Push-button_telephonehttp://en.wikipedia.org/wiki/Push-button_telephonehttp://en.wikipedia.org/wiki/Push-button_telephonehttp://en.wikipedia.org/wiki/ITU-Thttp://en.wikipedia.org/wiki/ITU-Thttp://en.wikipedia.org/wiki/ITU-Thttp://en.wikipedia.org/wiki/Q.23http://en.wikipedia.org/wiki/Q.23http://en.wikipedia.org/wiki/Q.23http://en.wikipedia.org/wiki/Q.23http://en.wikipedia.org/wiki/ITU-Thttp://en.wikipedia.org/wiki/Push-button_telephone


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DTMF keypad layout.

DTMF dialing

Menu

0:00How DTMF dialing sounds.

Problems playing this file? Seemedia help.

The engineers had envisioned phones being used to access computers, and surveyed a number of

companies to see what they would need for this role. This led to the addition of thenumber sign(#, ''pound'' or "diamond" in this context, "hash", "square" or "gate" in the UK, and "octothorpe''

by the original engineers) andasteriskor "star" (*) keys as well as a group of keys for menu

selection: A, B, C and D. In the end, the lettered keys were dropped from most phones, and it

was many years before these keys became widely used forvertical service codessuch as *67 inthe United States of America and Canada to suppresscaller ID.

Publicpayphonesthat accept credit cards use these additional codes to send the information from

themagnetic strip.

TheUnited States Armed Forcesalso used the letters, relabeled, in their now-defunctAUTOVONtelephone system.

[2]Here they were used before dialing the phone in order to give

some calls priority, cutting in over existing calls if need be. The idea was to allow important

traffic to get through every time. The levels of priority available were Flash Override (A), Flash(B), Immediate (C), and Priority (D), with Flash Override being the highest priority. Pressing one

of these keys gave one's call priority, overriding other conversations on the network. Pressing C,

Immediate, before dialing would make the switch first look for any free lines, and if all lines
http://en.wikipedia.org/wiki/File:DTMF_dialing.ogghttp://en.wikipedia.org/wiki/File:DTMF_dialing.ogghttp://en.wikipedia.org/wiki/Wikipedia:Media_helphttp://en.wikipedia.org/wiki/Wikipedia:Media_helphttp://en.wikipedia.org/wiki/Wikipedia:Media_helphttp://en.wikipedia.org/wiki/Number_signhttp://en.wikipedia.org/wiki/Number_signhttp://en.wikipedia.org/wiki/Number_signhttp://en.wikipedia.org/wiki/Octothorpehttp://en.wikipedia.org/wiki/Octothorpehttp://en.wikipedia.org/wiki/Asteriskhttp://en.wikipedia.org/wiki/Asteriskhttp://en.wikipedia.org/wiki/Asteriskhttp://en.wikipedia.org/wiki/Vertical_service_codehttp://en.wikipedia.org/wiki/Vertical_service_codehttp://en.wikipedia.org/wiki/Vertical_service_codehttp://en.wikipedia.org/wiki/Caller_IDhttp://en.wikipedia.org/wiki/Caller_IDhttp://en.wikipedia.org/wiki/Caller_IDhttp://en.wikipedia.org/wiki/Payphonehttp://en.wikipedia.org/wiki/Payphonehttp://en.wikipedia.org/wiki/Payphonehttp://en.wikipedia.org/wiki/Magnetic_striphttp://en.wikipedia.org/wiki/Magnetic_striphttp://en.wikipedia.org/wiki/Magnetic_striphttp://en.wikipedia.org/wiki/United_States_Armed_Forceshttp://en.wikipedia.org/wiki/United_States_Armed_Forceshttp://en.wikipedia.org/wiki/United_States_Armed_Forceshttp://en.wikipedia.org/wiki/Autovonhttp://en.wikipedia.org/wiki/Autovonhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#cite_note-2http://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#cite_note-2http://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#cite_note-2http://en.wikipedia.org/wiki/File:DTMF_keypad_layout.svghttp://en.wikipedia.org/wiki/File:DTMF_keypad_layout.svghttp://en.wikipedia.org/wiki/File:DTMF_keypad_layout.svghttp://en.wikipedia.org/wiki/File:DTMF_keypad_layout.svghttp://en.wikipedia.org/wiki/File:DTMF_keypad_layout.svghttp://en.wikipedia.org/wiki/File:DTMF_keypad_layout.svghttp://en.wikipedia.org/wiki/File:DTMF_keypad_layout.svghttp://en.wikipedia.org/wiki/File:DTMF_keypad_layout.svghttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#cite_note-2http://en.wikipedia.org/wiki/Autovonhttp://en.wikipedia.org/wiki/United_States_Armed_Forceshttp://en.wikipedia.org/wiki/Magnetic_striphttp://en.wikipedia.org/wiki/Payphonehttp://en.wikipedia.org/wiki/Caller_IDhttp://en.wikipedia.org/wiki/Vertical_service_codehttp://en.wikipedia.org/wiki/Asteriskhttp://en.wikipedia.org/wiki/Octothorpehttp://en.wikipedia.org/wiki/Number_signhttp://en.wikipedia.org/wiki/Wikipedia:Media_helphttp://en.wikipedia.org/wiki/File:DTMF_dialing.ogg


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were in use, it would disconnect any non-priority calls, and then any priority calls. Flash

Override will kick every other call off the trunks between the origin and destination.

Consequently, it was limited to theWhite House Communications Agency.

Precedence dialing is still done on the military phone networks, but using number combinations

(Example: Entering 93 before a number is a priority call) rather than the separate tones and theGovernment Emergency Telecommunications Servicehas superseded AUTOVON for any

civilian priority telephone company access.

Present-day uses of the A, B, C and D keys on telephone networks are few, and exclusive to

network control. For example, the A key is used on some networks to cycle through different

carriers at will (thereby listening in on calls). Their use is probably prohibited by most carriers.The A, B, C and D tones are used in radio phone patch and repeater operations to allow, among

other uses, control of the repeater while connected to an active phone line.

The *, #, A, B, C and D keys are still widely used worldwide byamateur radiooperators for

repeater control, remote-base operations and some telephone communications systems.

DTMF tones are also used by some cable television networks and radio networks to signal the

local cable company/network station to insert a local advertisement or station identification.

These tones were often heard during a station ID preceding a local ad insert. Previously,terrestrial television stations also used DTMF tones to shut off and turn on remote transmitters.

DTMF signaling tones can also be heard at the start or end of someVHS(Video Home System)cassette tapes. Information on the master version of the video tape is encoded in the DTMF tone.

The encoded tone provides information to automatic duplication machines, such as format,

duration and volume levels, in order to replicate the original video as closely as possible.

DTMF tones are sometimes used incaller IDsystems to transfer the caller ID information, but in

the United States onlyBell 202modulatedFSKsignaling is used to transfer the data.

Keypad

1209 Hz on 697 Hz to make the 1 tone

Main article:Telephone keypad
http://en.wikipedia.org/wiki/White_House_Communications_Agencyhttp://en.wikipedia.org/wiki/White_House_Communications_Agencyhttp://en.wikipedia.org/wiki/White_House_Communications_Agencyhttp://en.wikipedia.org/wiki/Government_Emergency_Telecommunications_Servicehttp://en.wikipedia.org/wiki/Government_Emergency_Telecommunications_Servicehttp://en.wikipedia.org/wiki/Amateur_radiohttp://en.wikipedia.org/wiki/Amateur_radiohttp://en.wikipedia.org/wiki/Amateur_radiohttp://en.wikipedia.org/wiki/VHShttp://en.wikipedia.org/wiki/VHShttp://en.wikipedia.org/wiki/VHShttp://en.wikipedia.org/wiki/Caller_IDhttp://en.wikipedia.org/wiki/Caller_IDhttp://en.wikipedia.org/wiki/Caller_IDhttp://en.wikipedia.org/wiki/Bell_202_modemhttp://en.wikipedia.org/wiki/Bell_202_modemhttp://en.wikipedia.org/wiki/Bell_202_modemhttp://en.wikipedia.org/wiki/Frequency-shift_keyinghttp://en.wikipedia.org/wiki/Frequency-shift_keyinghttp://en.wikipedia.org/wiki/Frequency-shift_keyinghttp://en.wikipedia.org/wiki/Telephone_keypadhttp://en.wikipedia.org/wiki/Telephone_keypadhttp://en.wikipedia.org/wiki/Telephone_keypadhttp://en.wikipedia.org/wiki/File:MultiTone1.pnghttp://en.wikipedia.org/wiki/File:MultiTone1.pnghttp://en.wikipedia.org/wiki/File:MultiTone1.pnghttp://en.wikipedia.org/wiki/File:MultiTone1.pnghttp://en.wikipedia.org/wiki/Telephone_keypadhttp://en.wikipedia.org/wiki/Frequency-shift_keyinghttp://en.wikipedia.org/wiki/Bell_202_modemhttp://en.wikipedia.org/wiki/Caller_IDhttp://en.wikipedia.org/wiki/VHShttp://en.wikipedia.org/wiki/Amateur_radiohttp://en.wikipedia.org/wiki/Government_Emergency_Telecommunications_Servicehttp://en.wikipedia.org/wiki/White_House_Communications_Agency


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The DTMF keypad is laid out in a 44 matrix in which each row represents a lowfrequency and

each column represents a highfrequency. Pressing a single key sends asinusoidaltone for each

of the two frequencies. For example, the key 1 produces a superposition of tones of 697 and1209hertz(Hz). Initial pushbutton designs employed levers, so that each button activated two

contacts. The tones are decoded by the switching center to determine the keys pressed by the

user.

DTMF keypad frequencies (with sound clips)

1209 Hz 1336 Hz 1477 Hz 1633 Hz

697 Hz 1 2 3 A

770 Hz 4 5 6 B

852 Hz 7 8 9 C

941 Hz * 0 # D

Special tone frequenciesIt has been suggested that this article bemergedintoCall-progress tone.(Discuss)Proposed since June 2011.

National telephone systems define additional tones to indicate the status of lines, equipment, or

the result of calls with special tones. Such tones are standardized in each country and may

consist of single or multiple frequencies. Most European countries use a single precise frequency

of 425 Hz, where the United States uses a dual frequency system.

Event Low frequency High frequency

Busy signal(US) 480 Hz 620 Hz

Ringback tone(US) 440 Hz 480 Hz

Dial tone(US) 350 Hz 440 Hz

The tone frequencies, as defined by thePrecise Tone Plan,are selected such thatharmonicsand

intermodulationproducts will not cause an unreliable signal. No frequency is a multiple of

another, the difference between any two frequencies does not equal any of the frequencies, andthe sum of any two frequencies does not equal any of the frequencies. The frequencies were

initially designed with aratioof 21/19, which is slightly less than awhole tone.The frequencies

may not vary more than 1.8% from their nominal frequency, or the switching center will ignore

the signal. The high frequencies may be the same volume asor louder thanthe lowfrequencies when sent across the line. The loudness difference between the high and low

frequencies can be as large as 3decibels(dB) and is referred to as "twist." The duration of the

tone should be at least 537 ms.[3

]

European Tones:

Event Low frequency High frequency
http://en.wikipedia.org/wiki/Sinusoidalhttp://en.wikipedia.org/wiki/Sinusoidalhttp://en.wikipedia.org/wiki/Sinusoidalhttp://en.wikipedia.org/wiki/Hertzhttp://en.wikipedia.org/wiki/Hertzhttp://en.wikipedia.org/wiki/Hertzhttp://upload.wikimedia.org/wikipedia/commons/b/bf/Dtmf1.ogghttp://upload.wikimedia.org/wikipedia/commons/b/bf/Dtmf1.ogghttp://upload.wikimedia.org/wikipedia/commons/7/7d/Dtmf2.ogghttp://upload.wikimedia.org/wikipedia/commons/7/7d/Dtmf2.ogghttp://upload.wikimedia.org/wikipedia/commons/2/28/Dtmf3.ogghttp://upload.wikimedia.org/wikipedia/commons/2/28/Dtmf3.ogghttp://upload.wikimedia.org/wikipedia/commons/d/d5/DtmfA.ogghttp://upload.wikimedia.org/wikipedia/commons/9/9f/Dtmf4.ogghttp://upload.wikimedia.org/wikipedia/commons/9/9f/Dtmf4.ogghttp://upload.wikimedia.org/wikipedia/commons/1/1c/Dtmf5.ogghttp://upload.wikimedia.org/wikipedia/commons/1/1c/Dtmf5.ogghttp://upload.wikimedia.org/wikipedia/commons/7/7b/Dtmf6.ogghttp://upload.wikimedia.org/wikipedia/commons/7/7b/Dtmf6.ogghttp://upload.wikimedia.org/wikipedia/commons/5/5a/DtmfB.ogghttp://upload.wikimedia.org/wikipedia/commons/5/5a/DtmfB.ogghttp://upload.wikimedia.org/wikipedia/commons/9/9f/Dtmf7.ogghttp://upload.wikimedia.org/wikipedia/commons/9/9f/Dtmf7.ogghttp://upload.wikimedia.org/wikipedia/commons/f/f7/Dtmf8.ogghttp://upload.wikimedia.org/wikipedia/commons/f/f7/Dtmf8.ogghttp://upload.wikimedia.org/wikipedia/commons/5/59/Dtmf9.ogghttp://upload.wikimedia.org/wikipedia/commons/5/59/Dtmf9.ogghttp://upload.wikimedia.org/wikipedia/commons/9/96/DtmfC.ogghttp://upload.wikimedia.org/wikipedia/commons/9/96/DtmfC.ogghttp://upload.wikimedia.org/wikipedia/commons/e/e7/DtmfStar.ogghttp://upload.wikimedia.org/wikipedia/commons/e/e7/DtmfStar.ogghttp://upload.wikimedia.org/wikipedia/commons/2/2d/Dtmf0.ogghttp://upload.wikimedia.org/wikipedia/commons/2/2d/Dtmf0.ogghttp://upload.wikimedia.org/wikipedia/commons/c/c4/Dtmf-.ogghttp://upload.wikimedia.org/wikipedia/commons/c/c4/Dtmf-.ogghttp://upload.wikimedia.org/wikipedia/commons/9/99/DtmfD.ogghttp://en.wikipedia.org/wiki/Wikipedia:Merginghttp://en.wikipedia.org/wiki/Wikipedia:Merginghttp://en.wikipedia.org/wiki/Wikipedia:Merginghttp://en.wikipedia.org/wiki/Call-progress_tonehttp://en.wikipedia.org/wiki/Call-progress_tonehttp://en.wikipedia.org/wiki/Call-progress_tonehttp://en.wikipedia.org/wiki/Talk:Call-progress_tonehttp://en.wikipedia.org/wiki/Talk:Call-progress_tonehttp://en.wikipedia.org/wiki/Talk:Call-progress_tonehttp://en.wikipedia.org/wiki/Busy_signal_%28telephony%29http://en.wikipedia.org/wiki/Busy_signal_%28telephony%29http://en.wikipedia.org/wiki/Ringback_tonehttp://en.wikipedia.org/wiki/Ringback_tonehttp://en.wikipedia.org/wiki/Dial_tonehttp://en.wikipedia.org/wiki/Dial_tonehttp://en.wikipedia.org/wiki/Precise_Tone_Planhttp://en.wikipedia.org/wiki/Precise_Tone_Planhttp://en.wikipedia.org/wiki/Precise_Tone_Planhttp://en.wikipedia.org/wiki/Harmonic_series_%28music%29http://en.wikipedia.org/wiki/Harmonic_series_%28music%29http://en.wikipedia.org/wiki/Harmonic_series_%28music%29http://en.wikipedia.org/wiki/Intermodulationhttp://en.wikipedia.org/wiki/Intermodulationhttp://en.wikipedia.org/wiki/Ratiohttp://en.wikipedia.org/wiki/Ratiohttp://en.wikipedia.org/wiki/Ratiohttp://en.wikipedia.org/wiki/Whole_tonehttp://en.wikipedia.org/wiki/Whole_tonehttp://en.wikipedia.org/wiki/Whole_tonehttp://en.wikipedia.org/wiki/Decibelhttp://en.wikipedia.org/wiki/Decibelhttp://en.wikipedia.org/wiki/Decibelhttp://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#cite_note-3http://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#cite_note-3http://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#cite_note-3http://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#cite_note-3http://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling#cite_note-3http://en.wikipedia.org/wiki/Decibelhttp://en.wikipedia.org/wiki/Whole_tonehttp://en.wikipedia.org/wiki/Ratiohttp://en.wikipedia.org/wiki/Intermodulationhttp://en.wikipedia.org/wiki/Harmonic_series_%28music%29http://en.wikipedia.org/wiki/Precise_Tone_Planhttp://en.wikipedia.org/wiki/Dial_tonehttp://en.wikipedia.org/wiki/Ringback_tonehttp://en.wikipedia.org/wiki/Busy_signal_%28telephony%29http://en.wikipedia.org/wiki/Talk:Call-progress_tonehttp://en.wikipedia.org/wiki/Call-progress_tonehttp://en.wikipedia.org/wiki/Wikipedia:Merginghttp://upload.wikimedia.org/wikipedia/commons/9/99/DtmfD.ogghttp://upload.wikimedia.org/wikipedia/commons/c/c4/Dtmf-.ogghttp://upload.wikimedia.org/wikipedia/commons/2/2d/Dtmf0.ogghttp://upload.wikimedia.org/wikipedia/commons/e/e7/DtmfStar.ogghttp://upload.wikimedia.org/wikipedia/commons/9/96/DtmfC.ogghttp://upload.wikimedia.org/wikipedia/commons/5/59/Dtmf9.ogghttp://upload.wikimedia.org/wikipedia/commons/f/f7/Dtmf8.ogghttp://upload.wikimedia.org/wikipedia/commons/9/9f/Dtmf7.ogghttp://upload.wikimedia.org/wikipedia/commons/5/5a/DtmfB.ogghttp://upload.wikimedia.org/wikipedia/commons/7/7b/Dtmf6.ogghttp://upload.wikimedia.org/wikipedia/commons/1/1c/Dtmf5.ogghttp://upload.wikimedia.org/wikipedia/commons/9/9f/Dtmf4.ogghttp://upload.wikimedia.org/wikipedia/commons/d/d5/DtmfA.ogghttp://upload.wikimedia.org/wikipedia/commons/2/28/Dtmf3.ogghttp://upload.wikimedia.org/wikipedia/commons/7/7d/Dtmf2.ogghttp://upload.wikimedia.org/wikipedia/commons/b/bf/Dtmf1.ogghttp://en.wikipedia.org/wiki/Hertzhttp://en.wikipedia.org/wiki/Sinusoidal


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Busy signal(UK) 400 Hz ----

Busy signal(Most of Europe) 425 Hz ----

Ringback tone(UK & Ireland) 400 Hz 450 Hz

Ringback tone(Most of Europe) 425 Hz ----

Dial tone(UK) 350 Hz 440 HzDial tone(Most of Europe) 425 Hz ----

As with othermulti-frequency receivers,DTMF was originally decoded by tuned filter banks.

Late in the 20th century most were replaced withdigital signal processors.Although DTMF canbe decoded using any frequency domain transform (such as the popularFast Fourier transform),

theGoertzel algorithmis a common algorithm to consider due to its high performance for

DTMF.

DTMF Decoder / Encoder

DTMF Decoderis a very easy to use program to decode DTMF dial tones found ontelephone lines with touch tone phones.DTMF Decoderis also used for receiving data transmissions over the air inamateur radio frequency bands.

The following are the frequencies used for the DTMF (dual-tone, multi-frequency)system, which is also referred to as tone dialling. The signal is encoded as a pairof sinusoidal (sine wave) tones from the table below which are mixed with eachother. DTMF is used by most PSTN (public switched telephone networks)systems for number dialling, and is also used for voice-response systems suchas telephone banking and sometimes over private radio networks to providesignalling and transferring of small amounts of data.
http://en.wikipedia.org/wiki/Busy_signal_%28telephony%29http://en.wikipedia.org/wiki/Busy_signal_%28telephony%29http://en.wikipedia.org/wiki/Busy_signal_%28telephony%29http://en.wikipedia.org/wiki/Busy_signal_%28telephony%29http://en.wikipedia.org/wiki/Ringback_tonehttp://en.wikipedia.org/wiki/Ringback_tonehttp://en.wikipedia.org/wiki/Ringback_tonehttp://en.wikipedia.org/wiki/Ringback_tonehttp://en.wikipedia.org/wiki/Dial_tonehttp://en.wikipedia.org/wiki/Dial_tonehttp://en.wikipedia.org/wiki/Dial_tonehttp://en.wikipedia.org/wiki/Dial_tonehttp://en.wikipedia.org/wiki/Multi-frequency_receiverhttp://en.wikipedia.org/wiki/Multi-frequency_receiverhttp://en.wikipedia.org/wiki/Multi-frequency_receiverhttp://en.wikipedia.org/wiki/Digital_signal_processorhttp://en.wikipedia.org/wiki/Digital_signal_processorhttp://en.wikipedia.org/wiki/Digital_signal_processorhttp://en.wikipedia.org/wiki/Fast_Fourier_transformhttp://en.wikipedia.org/wiki/Fast_Fourier_transformhttp://en.wikipedia.org/wiki/Fast_Fourier_transformhttp://en.wikipedia.org/wiki/Goertzel_algorithmhttp://en.wikipedia.org/wiki/Goertzel_algorithmhttp://en.wikipedia.org/wiki/Goertzel_algorithmhttp://en.wikipedia.org/wiki/Goertzel_algorithmhttp://en.wikipedia.org/wiki/Fast_Fourier_transformhttp://en.wikipedia.org/wiki/Digital_signal_processorhttp://en.wikipedia.org/wiki/Multi-frequency_receiverhttp://en.wikipedia.org/wiki/Dial_tonehttp://en.wikipedia.org/wiki/Dial_tonehttp://en.wikipedia.org/wiki/Ringback_tonehttp://en.wikipedia.org/wiki/Ringback_tonehttp://en.wikipedia.org/wiki/Busy_signal_%28telephony%29http://en.wikipedia.org/wiki/Busy_signal_%28telephony%29


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Table of DTMF frequencies (CCITT)

Symbol Tone B [Hz]1209 1336 1477 1633

ToneA

[Hz]

697 1 2 3 A

770 4 5 6 B

852 7 8 9 C

941 * 0 # D

Live tone signals are fed from telephone line or radio into soundcard ofcomputer. Either line- or microphone input jack is used. It is highlyrecommended to ensure galvanic decoupling between PC and telephone line orradio receiver. DTMF Decoder output is clear text consisting of the symbolsshown in table above. An exact log is displayed; when, which number wasdialled. This log is automatically stored into a log file for later exploration.


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System requirements:Windows 95 / 98 / Me / NT4 / 2000 / XP / Win 7 (see instructions below) Processor Pentium or higherProcessor clock 1Ghz256 MB RAM or more

5 MB free disk spaceSoundcard

Windows 7 specific instructions:Locate DTMF Decoder at it's Program folder location for example

"C:\Programs\HamRadioSoftware\......DTMFdecoder.exe"

Right click on the DTMFdecoder.exe file to access the properties

In the properties / compatibility table one must set: XP Service pack2


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Technology:Digital Signal Processing (DSP)Finest 5th order Gaussian Bandfilters with adjustable bandwith.

Excellent Signal to Noise Ratio (SNR)

More Info:Download and view theDTMF Decoder Help File

Download:15 Day Trial Version

Win XP: In case of any problems with execution of MRP40 underWin XP you should know that MRP40 is a Visual Basic programand requires theVB6 Runtime Filesto be installed. If you do not jethave the Visual Basic 6.0 Runtime files installed on your computer,please choose one of the download sites below. (1MB, freedownload )

Download VB RunTimeLib here!

Win 7: Do not install VB6 Runtime Libary! It is already included in Win7

Register for19.90 USD via PayPalThe key code to unlock DTMF-Decoder (turn into full version) will be be send toyou via email

Download theDTMF Encoder (Dial Tone Generator),it's Free! ( no costat all )
http://www.polar-electric.com/DTMF/DTMFhelp.chmhttp://www.polar-electric.com/DTMF/DTMFhelp.chmhttp://www.polar-electric.com/DTMF/DTMFhelp.chmhttp://www.polar-electric.com/DTMF/DTMFinstaller.exehttp://www.polar-electric.com/DTMF/DTMFinstaller.exehttp://www.polar-electric.com/DTMF/DTMFinstaller.exehttp://download.microsoft.com/download/vb60pro/install/6/Win98Me/EN-US/VBRun60.exehttp://download.microsoft.com/download/vb60pro/install/6/Win98Me/EN-US/VBRun60.exehttp://download.microsoft.com/download/vb60pro/install/6/Win98Me/EN-US/VBRun60.exehttp://download.microsoft.com/download/vb60pro/Redist/sp5/WIN98Me/EN-US/vbrun60sp5.exehttp://download.microsoft.com/download/vb60pro/Redist/sp5/WIN98Me/EN-US/vbrun60sp5.exehttp://www.polar-electric.com/DTMF/order.htmlhttp://www.polar-electric.com/DTMF/order.htmlhttp://www.polar-electric.com/DTMF/InstallDTMFencoder.exehttp://www.polar-electric.com/DTMF/InstallDTMFencoder.exehttp://www.polar-electric.com/DTMF/InstallDTMFencoder.exehttp://www.polar-electric.com/DTMF/InstallDTMFencoder.exehttp://www.polar-electric.com/DTMF/order.htmlhttp://download.microsoft.com/download/vb60pro/Redist/sp5/WIN98Me/EN-US/vbrun60sp5.exehttp://download.microsoft.com/download/vb60pro/install/6/Win98Me/EN-US/VBRun60.exehttp://www.polar-electric.com/DTMF/DTMFinstaller.exehttp://www.polar-electric.com/DTMF/DTMFhelp.chm


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Contact:Send your problems, suggestions, and questions to my e-mail: [email protected] (remove the letters "SPAM")

Related Links:

Decoder and Controller Products (Hardware)http://www.icircuits.com/

Soil moisture sensorsmeasure thewater contentinsoil.A soil moisture probe is made up ofmultiple soil moisture sensors. One common type of soil moisture sensors in commercial use is afrequency domain sensorsuch as a capacitance sensor. Another sensor, theneutron moisture

gauge,utilize the moderator properties of water for neutrons. Cheaper sensors -often for home

use- are based on two electrodes measuring the resistance of the soil. Sometimes this simply

consists of two bare (galvanized) wires, but there are also probes with wires embedded ingypsum. The bare wire sensor is extremely affected by soil salinity and pH. A driving rain can

temporarily remove ions from water in the soil making it less conductive - similar to a 'dry'
http://www.icircuits.com/prod_dtmf_main.htmlhttp://www.icircuits.com/prod_dtmf_main.htmlhttp://www.icircuits.com/prod_dtmf_main.htmlhttp://www.icircuits.com/prod_dtmf_main.htmlhttp://www.icircuits.com/http://www.icircuits.com/http://en.wikipedia.org/wiki/Water_contenthttp://en.wikipedia.org/wiki/Water_contenthttp://en.wikipedia.org/wiki/Water_contenthttp://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Frequency_domain_sensorhttp://en.wikipedia.org/wiki/Frequency_domain_sensorhttp://en.wikipedia.org/wiki/Neutron_moisture_gaugehttp://en.wikipedia.org/wiki/Neutron_moisture_gaugehttp://en.wikipedia.org/wiki/Neutron_moisture_gaugehttp://en.wikipedia.org/wiki/Neutron_moisture_gaugehttp://en.wikipedia.org/wiki/Neutron_moisture_gaugehttp://en.wikipedia.org/wiki/Neutron_moisture_gaugehttp://en.wikipedia.org/wiki/Frequency_domain_sensorhttp://en.wikipedia.org/wiki/Soilhttp://en.wikipedia.org/wiki/Water_contenthttp://www.icircuits.com/http://www.icircuits.com/prod_dtmf_main.htmlhttp://www.icircuits.com/prod_dtmf_main.html


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reading. Gypsum probes provide a constant source of ions, but they do not dry at the same time

as the soil surrounding it, and they are plagued by clogging from small soil particles.Time

domain transmission (TDT) and time domain reflectometry (TDR)is also used to measuremoisture content; water has a highdielectric constant;a higher water concentration causes a

higher average dielectric constant for the soil. The average dielectric constant can be sensed by

measuring the speed of propagation along a buried transmission line.

[1][2]

A new heat dissipativesensor using exact heating and cooling profiles (Patent Pending) from WaterGreat LLC providesanother accurate method of soil detection that is not affected by soil salinity, pH, soil compaction

and temperature. Heat dissipation sensors rely on the effective heatR-value (insulation)of soil.

Soil with additional water conducts heat more readily than dry soil. New precise inexpensivemicrocontrollers make this type of measurement possible.

[3]

Contents

1 Agriculture

2 Landscape irrigation

3 References 4 External links

Agriculture

Measuring soil moisture is important in agriculture to help farmers manage their irrigation

systems more efficiently. Not only are farmers able to generally use less water to grow a crop,

they are able to increase yields and the quality of the crop by better management of soil moistureduring critical plant growth stages.

Besides agriculture, there are many other disciplines using soil moisture sensors. Golf coursesare now using sensors to increase the efficiencies of their irrigation systems to prevent over

watering and leaching of fertilizers and other chemicals offsite.

Landscape irrigation

Inurbanandsuburbanareas,landscapesand residentiallawnsare using soil moisture sensors tointerface with an irrigation controller. Connecting a soil moisture sensor to a simple irrigation

clock will convert it into a "smart" irrigation controller that prevents an irrigation cycle when the

soil is wet.
http://en.wikipedia.org/wiki/Time_domain_reflectometryhttp://en.wikipedia.org/wiki/Time_domain_reflectometryhttp://en.wikipedia.org/wiki/Time_domain_reflectometryhttp://en.wikipedia.org/wiki/Time_domain_reflectometryhttp://en.wikipedia.org/wiki/Dielectric_constanthttp://en.wikipedia.org/wiki/Dielectric_constanthttp://en.wikipedia.org/wiki/Dielectric_constanthttp://en.wikipedia.org/wiki/Soil_moisture_sensor#cite_note-1http://en.wikipedia.org/wiki/Soil_moisture_sensor#cite_note-1http://en.wikipedia.org/wiki/Soil_moisture_sensor#cite_note-1http://en.wikipedia.org/wiki/R-value_%28insulation%29http://en.wikipedia.org/wiki/R-value_%28insulation%29http://en.wikipedia.org/wiki/R-value_%28insulation%29http://en.wikipedia.org/wiki/Soil_moisture_sensor#cite_note-3http://en.wikipedia.org/wiki/Soil_moisture_sensor#cite_note-3http://en.wikipedia.org/wiki/Soil_moisture_sensor#cite_note-3http://en.wikipedia.org/wiki/Soil_moisture_sensor#Agriculturehttp://en.wikipedia.org/wiki/Soil_moisture_sensor#Agriculturehttp://en.wikipedia.org/wiki/Soil_moisture_sensor#Landscape_irrigationhttp://en.wikipedia.org/wiki/Soil_moisture_sensor#Landscape_irrigationhttp://en.wikipedia.org/wiki/Soil_moisture_sensor#Referenceshttp://en.wikipedia.org/wiki/Soil_moisture_sensor#Referenceshttp://en.wikipedia.org/wiki/Soil_moisture_sensor#External_linkshttp://en.wikipedia.org/wiki/Soil_moisture_sensor#External_linkshttp://en.wikipedia.org/wiki/Urban_areahttp://en.wikipedia.org/wiki/Urban_areahttp://en.wikipedia.org/wiki/Urban_areahttp://en.wikipedia.org/wiki/Suburbanhttp://en.wikipedia.org/wiki/Suburbanhttp://en.wikipedia.org/wiki/Suburbanhttp://en.wikipedia.org/wiki/Gardenhttp://en.wikipedia.org/wiki/Gardenhttp://en.wikipedia.org/wiki/Gardenhttp://en.wikipedia.org/wiki/Lawnhttp://en.wikipedia.org/wiki/Lawnhttp://en.wikipedia.org/wiki/Lawnhttp://en.wikipedia.org/wiki/Lawnhttp://en.wikipedia.org/wiki/Gardenhttp://en.wikipedia.org/wiki/Suburbanhttp://en.wikipedia.org/wiki/Urban_areahttp://en.wikipedia.org/wiki/Soil_moisture_sensor#External_linkshttp://en.wikipedia.org/wiki/Soil_moisture_sensor#Referenceshttp://en.wikipedia.org/wiki/Soil_moisture_sensor#Landscape_irrigationhttp://en.wikipedia.org/wiki/Soil_moisture_sensor#Agriculturehttp://en.wikipedia.org/wiki/Soil_moisture_sensor#cite_note-3http://en.wikipedia.org/wiki/R-value_%28insulation%29http://en.wikipedia.org/wiki/Soil_moisture_sensor#cite_note-1http://en.wikipedia.org/wiki/Soil_moisture_sensor#cite_note-1http://en.wikipedia.org/wiki/Dielectric_constanthttp://en.wikipedia.org/wiki/Time_domain_reflectometryhttp://en.wikipedia.org/wiki/Time_domain_reflectometry

Project Synopsis

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Transcript of Project Synopsis