Difference between revisions of "IVRS"

From Karnataka Open Educational Resources
Jump to navigation Jump to search
 
(31 intermediate revisions by 2 users not shown)
Line 1: Line 1:
 
+
[http://karnatakaeducation.org.in/KOER/index.php/%E0%B2%90_%E0%B2%B5%E0%B2%BF_%E0%B2%86%E0%B2%B0%E0%B3%8D_%E0%B2%8E%E0%B2%B8%E0%B3%8D_%E0%B2%95%E0%B3%88%E0%B2%AA%E0%B2%BF%E0%B2%A1%E0%B2%BF ಕನ್ನಡದಲ್ಲಿ ನೋಡಿ]
 
==About==
 
==About==
  
 
IVRS(Interactive Voice Response System) is commonly used platform to reach people connected through mobile/telephones. This page is about how one can set it up and send Voice SMS at any place with minimal requirements.
 
IVRS(Interactive Voice Response System) is commonly used platform to reach people connected through mobile/telephones. This page is about how one can set it up and send Voice SMS at any place with minimal requirements.
 +
In the school context we can us this software to communicate with parents easily. Most of our school parents are not capable to read sms or letters. from IVRS software we can reach all parents even if they are using basic mobile phones. From IVRS, schools can reach all parents easily by sending voice call. teachers can record their voice message and then send it through IVRS to parents mobile numbers. Same time parents will receive the call and they will hear their recorded message.
  
 
== Installation and Deployment==
 
== Installation and Deployment==
This page helps anyone to deploy IVRS to send voice SMS from your [[Kalpavriksha|Kalpavriksha(Ubuntu)]] machine with a data card. Call charges as per network would apply. Below instructions were modified from [http://mojolab.org/archives/50 Mojolab] site where this was used to install [https://github.com/ccidmysore/swara Swar]a software. This was tested on [[Kalpavriksha|Kalpavriksha(Ubuntu)]] with Huwawei E173 and is currently used in [[GHS Dommaluru | Government High School, Domlur]]. An opensource IVRS program called [http://asterisk.org Asterisk] is used to run Swara software.
+
This page helps anyone to deploy IVRS to send voice SMS from your [[Kalpavriksha|Kalpavriksha(Ubuntu)]] machine with a data card. Call charges as per network would apply. Below instructions were modified from [http://mojolab.org/archives/50 Mojolab] site where this was used to install [https://github.com/ccidmysore/swara Swara] software. This was tested on [[Kalpavriksha|Kalpavriksha(Ubuntu)]] with Huwawei E173 and is currently used in [[GHS Dommaluru | Government High School, Domlur]]. An opensource IVRS program called [http://asterisk.org Asterisk] is used to run Swara software.<br>
  
Make sure each step below is successful without errors:
+
'''Please[http://karnatakaeducation.org.in/KOER/en/index.php/IVRS_Installation Click here]''' to know detailed installation steps. <br>
--------------------------------------------------------------------------
 
  
Step 1: Install ssh, lamp and other required packages
+
--------------------------------------------------------------------
sudo apt-get install openssh-client openssh-server
+
Please enter the given commands in terminal without any mistakes. After Installation completes please download '''VoiceBlast''' application from website. save this VoiceBlast file in '''Downloads''' folder on your computer. While processing with IVRS, we need to save our recorded audios and phone number list only in the folder.
sudo apt-get install tasksel
 
sudo tasksel install lamp-server
 
sudo apt-get install ncurses-dev libxml2-dev g++
 
sudo apt-get install lame mysql-server wget gcc g++ bison zlib1g zlib-bin openssl php5-mysql php5 apache2 python-mysqldb
 
  
Step 2: Enter superuser mode and run below commands to install python packages required for asterisk.
+
=Contexts=
su -
+
==Parents Teachers Meetings==
<Enter your password>
+
When schools are planning to have parent-teacher meeting at school to dicsuss strudents learning progress, attendance and ther issues, school can use IVRS to invite parents to this meeting. school can request parents through IVRS voice call to participate in Parent-Teacher meeting.<br>
apt-get install python-setuptools
+
Examples:
easy_install MySQL-Python
+
#[https://soundcloud.com/gurumurthy-kasinathan/call-to-parents-to-attend-meeting-ejipura Ejipura IVRS Message to 8&9 students parents]
easy_install tweepy
+
#[https://soundcloud.com/gurumurthy-kasinathan/call-to-10th-parents-to-attend-meeting-ejipura Ejipura IVRS Message to 10th students parents]
easy_install oauth2
+
#[https://soundcloud.com/gurumurthy-kasinathan/tankgarden-school-ivrs-clip-call-for-parents-meeting-1 Tank Garden school IVRS Message to parents]
easy_install stopwatch
+
#[https://soundcloud.com/gurumurthy-kasinathan/call-to-parents-to-attend-meeting-agara Agara school IVRS message to parents]
easy_install simplejson
+
#[https://soundcloud.com/gurumurthy-kasinathan/bagrahara-school-audio-on-parents-meeting-call B.Agarahara School IVRS message to parents]
  
Step 3: Disabling your firewall
+
==School Level Programmes==
sudo ufw disable
+
Same like parent-teacher meeting school can also communicate parents about school level programmes like National festival celebration, Cultural activities, community meetings, anniversary programmes etc. It will encourage parents to attend school programmes.<br>
 +
Example:
 +
#[https://soundcloud.com/gurumurthy-kasinathan/audugodi-call-to-parents-about-kudremukha-programme2 Adugodi school IVRS message to parents to attend school programme]
  
 +
==Special Classes in School==
 +
In schools, for 10th students there will be regular special classess now. and its important to inform parents about special class timings. So that they will be aware about their children and it will help parents to send their children on early hours to school. Same information can send through IVRS voice calls to parents.<br>
 +
Example:
 +
#[https://soundcloud.com/gurumurthy-kasinathan/yediyuru-call-to-parenst-abour-special-class Yediyuru school IVRS message to parents]
  
Step 4: Installing asterisk. Note install only this version of asterisk in this way only. Go to http://downloads.asterisk.org/pub/telephony/asterisk/old-releases/  link and download '''asterisk-1.6.2.23.tar.gz''' file. Run below commands to install it
+
==Progress Card==
cd /usr/src
+
School intention is to send progress card to home is to  make parents awarded about their children progress. Most of the time students will not show their Progress card to parents and they will make parents signature instead of parents. In this context school can send a voice call through IVRS to inform about progress card issued and request them to see the progress and to make signature.and also school can request parents to meet class teachers if students progress is not good.
sudo tar -xvzf ~/Downloads/asterisk-1.6.2.23.tar.gz
 
sudo apt-get install ncurses-dev libxml2-dev g++
 
cd asterisk-1.6.2.23
 
sudo ./configure
 
sudo make clean
 
sudo make
 
sudo make install
 
sudo make samples
 
  
Step 5: Create new database for swara in mysql
+
==Irregular and Slow learn Students==
/usr/bin/mysql_secure_installation (Answer yes to every question, set a new password for the root user)
+
If students are not attending classes regularly, most of the time parents may not aware about it. If school inform parents about their children absence, then parents can enquire and observe their children. and also school can make communication to parents about their children poor learning progress. and here school can insist parents to focus on their children reading at home. School can make list of Irregular and Slow learn Students and can send voice calls to those parents through IVRS.
mysql -u root -p
 
mysql>create database swara;
 
mysql>exit
 
  
Step 6: Enter superuser mode and run below commands to install and setup Swara
+
For Example:
wget https://github.com/ccidmysore/swara/tarball/developers
+
#[https://soundcloud.com/gurumurthy-kasinathan/ejipura-school-ivrs-call-to-parents Ejipura school IVRS message to parents] <br>
mv developers /opt/swara.tgz
+
#[https://soundcloud.com/gurumurthy-kasinathan/sets/tcol-schools-ivrs-audio-clips Wilson Garden school IVRS message to parents]
cd /opt
+
#[https://soundcloud.com/gurumurthy-kasinathan/beguru-school-ivrs-audio-about-irregular-students-iformatiion Beguru school IVRS message to parents]
tar xvzf swara.tgz
 
mv ccidmysore-swara-1cc734f swara
 
cd /var/www/
 
ln -s /opt/swara/web /var/www/swara
 
  
Step 7: Set up symlinks and Asterisk configurations
+
==To make reading at home==
 +
It will help students learning if parents are aware about their children education. They should always encourage children to engage in reading and writing at home. school can request parents to focus on their children reading /writing activities at home.
  
  ln -s /opt/swara/web /var/www/html
+
For Example  
<create folder name as asterisk in /usr/share>
+
#[https://soundcloud.com/gurumurthy-kasinathan/dommaluru-ivrs-call-to-parents-to-prepare-their-child-to-exam Dommaluru school IVRS message-1 to parents]
ln -s /opt/swara/bin /usr/share/asterisk/agi-bin
+
#[https://soundcloud.com/gurumurthy-kasinathan/dommaluru-hm-call-to-parents-to-make-child-reading-at-home Dommaluru school IVRS message-2 to parents]
ln -s /opt/swara/bin /usr/share/asterisk/sounds
+
#[https://soundcloud.com/gurumurthy-kasinathan/hombegowdabhs Hombegowda high school IVRS message to parents]
cp /opt/swara/conf/extensions.conf /opt/swara/conf/sip.conf /etc/asterisk
+
#[https://soundcloud.com/gurumurthy-kasinathan/vijaya-high-school-ivrs-message-1-to-parents Vijaya high school IVRS message-1 to parents]
cd /usr/share/asterisk
+
#[https://soundcloud.com/gurumurthy-kasinathan/vijaya-high-school-ivrs-message-2-to-parents-about-special-classes Vijaya high school IVRS message-2 to parents about special classes]
mkdir orig && mv sounds agi-bin orig/
+
#[https://soundcloud.com/gurumurthy-kasinathan/mes-hm MES high school IVRS message to parents]
ln -s /opt/swara/bin agi-bin && ln -s /opt/swara/sounds sounds
+
#[https://soundcloud.com/gurumurthy-kasinathan/gangamma-hombegowda-girls-high-school-ivrs-message-2-to-parents-about-special-classes Gangamma Hombegowda girls high school IVRS message to parents]
cd /opt/swara/conf
 
<Edit swara.conf and put in your database password>
 
sudo gedit swara.conf
 
cp swara.conf /etc
 
cp extensions.conf /etc/asterisk
 
cp sip.conf /etc/asterisk
 
mysql -u root -p swara < swaradb.sql
 
cd /opt/swara/web
 
mkdir /opt/swara/sounds/web && ln -s /opt/swara/sounds/web audio
 
ln -s /opt/swara/sounds/web upload
 
chmod a+rwx -R /opt/swara
 
touch /var/log/swara.log
 
chmod a+rwx -R /var/log/swara.log
 
  
Step 8: Download and install chan_dongle-1.1.r14.tgz from https://code.google.com/archive/p/asterisk-chan-dongle/downloads
+
==School Admission==
cd ~/Downloads
+
Schools may have several activities to increase school strength. One of the best idea is, they can contact nearby HPS schools and can get final class students database with parents contact numbers. By collecting parents contact numbers school can send voice calls to those parents and explaining about the facilities available in the school and can request them to admit their child to this our school.   
tar -xvf chan_dongle-1.1.r14.tgz
 
cd chan_dongle-1.1.r14
 
sudo ./configure
 
sudo make
 
  sudo make install
 
  
Step 9: Setup chan dongle with Asterisk:
+
Example:
cd ~/Downloads/chan_dongle-1.1.r14/etc/
+
# [https://soundcloud.com/gurumurthy-kasinathan/dommaluru-ivrs-call-to-hps-parents-for-admission Dommaluru School IVRS message to HPS Parents].
<Copy the dongle.conf file to /etc/asterisk/>
 
sudo cp ~/Downloads/chan_dongle-1.1.r14/etc/dongle.conf /etc/asterisk/
 
<Open the file /etc/asterisk/dongle.conf and set the IMEI setting with the IMEI number of the dongle>
 
sudo gedit /etc/asterisk/dongle.conf
 
<Save and close the dongle.conf file after adding IMEI number of the dongle>
 
 
  
Step 10: Setup Asterisk and swara to make calls:
+
==Other Contexts==
<Open the file "/etc/asterisk/dongle.conf" and set the values for Context as "from-sip" and exten as "swara-local">
+
#School Level Programmes
sudo gedit /etc/asterisk/dongle.conf
+
#Community Programmes
<Save and close the dongle.conf file
+
#Health Camps
+
#School Trips
 +
#Scholarship Distribution
 +
#Exam Time Table anouncement
 +
#School Holiday delcaration
 +
#Sports activities
 +
etc
  
Step 11: Download and extract folders from http://karnatakaeducation.org.in/swarabinFiles.zip to /opt/swara/
+
=Preparation to use IVRS=
cd ~/Downloads
+
#Need to arrange a data card for school.Generally data cards has been used for internet purpose, but for IVRS we need to have voice call option with outgoing call facility. Internet is required only for IVRS installation and its not essential to run IVRS.  
wget http://karnatakaeducation.org.in/swarabinFiles.zip
+
#Before sending voice calls, we need to think about message and context. its better to script the message.
unzip swarabinFiles.zip
+
#Scripted message can be recorded by using below steps:
cd swarabinFiles/
+
##We can make voice record by desktop computers. but here head set/mike is compulsory to record. because desktop computers will not have direct input option. in Ubuntu computers we will use '''Audacity''' to record.
sudo cp -r bin/ /opt/swara/
+
##Through laptops also we can record the voice, here we directly use the ubuntu technology "Audacity" to record the voice.To have good voice recording we must use mike or headsets.   
sudo cp -r conf/ /opt/swara/
 
  sudo cp -r libs/ /opt/swara/
 
sudo cp -r tools/ /opt/swara/
 
  
 +
==Methods of recording on a computer or laptop==
 +
Be prepare with script and then record it in computer.  To record we can use '''Audacity''' application in UBUNTU,  to open audacity in your computer / laptop  go to Application – Sound and Video – Audacity.  then in that by pressing the record ('''red button''') button you can start recording process. To save your recording go to  FILE and then click on Export.  Here while saving File Format must be .wav format. also select VoiceBlast folder from Downloads to keep this recording clip. And then click on Export, it will save in your computer. 
 +
 +
NOTE : While recording the voice in Audacity the frequency must be set to  8000GHz . see the picture 1<br>
 +
And Audio input channel should 1.Mono input channel, to set this please go to menu bar and click on sterio drop down option, see the picture 2<br>
 +
1. [[File:Audacity 2.png|200px]]       
 +
2. [[File:Audacity1.png|400px]]
  
Step 12: Setup Asterisk to use swara configs
+
==Methods of recording on mobile==
<Edit /etc/asterisk/extensions.conf>
+
Be prepare with script and then record it in by your mobile phone. Normally in all android sets you will have  Voice Recording option and you can use different applications also. In that “Tape-a-talk” application is most popular one and you can download this from your android playstore.
sudo gedit /etc/asterisk/extensions.conf
+
In your mobile you can do Voice Recording by opening the application in silent area. Later you can transfer this recorded voice to computer. In computer through Audacity you can make changes to your recorded voice and you can save in .wav format and keep that in your computer or laptop in Downloads folder , in that VoiceBlast folder. <br>
<Under [from-sip], change>
+
NOTE : NOTE : While recording the voice in Audacity the frequency must be set to 8000GHz.
exten => swara-local,n,AGI(menu_system_localized.py)
 
to
 
exten => swara-local,n,AGI(/opt/swara/bin/menu_system_localized1.py)
 
<Save and close the file after changing as shown above>
 
 
 
 
 
Installation is now completed. Now to run the IVRS and send voice-sms, connect the USB dongle to the USB drive and follow below steps:
 
----------------------
 
 
 
1. Open the terminal. change to root using the command "su -"
 
2. Now run the command "asterisk -vvvvvvc". This should run without fail and the CLI prompt should come
 
3. On the CLI command prompt run the command "agi set debug on"
 
4. Call to the number and you should hear the IVR prompt
 
5. Stop to this run "core stop gracefully"
 
6. Stop and Restart " core restrat gracefully"
 
7. check Dongle is ready "dongle show devices"
 
 
 
==Sending Voice-SMS==
 
 
 
Below steps can be followed to send Voice-SMS with above set-up.
 
1. Open Voice-SMS window.
 
2. Select your Audio file in *.wav format.
 
  3. Select text file with list of numbers to which the message has to be sent.
 
4. Enter the duration in seconds.
 
  5. Click on Send to start the calls.
 
 
 
==Getting Good Quality Audio for Voice-SMS==
 
  
Usually in school ambiance, it is difficult to get good quality audio recordings for sending Voice SMS. Great quality audio is very essential for your message to reach your intended audience. Below are few steps one can follow to ensure this:
+
=Method to send IVRS recorded voice=
 +
#After completing voice recording, you can send recorded voice through IVRS .
 +
#First you have to insert your data card to computer.
 +
# Then go to '''Application''' > '''Office''' > IVRS 1.
 +
Here you will see the running terminal.
 +
#Again go to '''Application''' > '''Office''' > IVRS 2
  
Before proceeding with below steps, please ensure you have the following with you - Android phone, Audacity software, [https://play.google.com/store/apps/details?id=name.markus.droesser.tapeatalkpro Tape-a-talk] app on your Android and earphones if available.
+
After this, you will the picture of the window which you are seeing below. here you have to select the recorded voice list option, later select the phone numbers to whom you have to send the recorded voice. you can mention the duration of the recorded voice.It should be minimum of 15 seconds.<br>
 +
[[File:VoiceBlast.png|400px]]
  
# Install [https://play.google.com/store/apps/details?id=name.markus.droesser.tapeatalkpro Tape-a-talk] app on your Android phone.
+
next click on '''SEND''' button. later you will see the progress of sending the voice in one of the terminal. in this you can see who all received the call. who have not received and even switched off numbers list also.
# This IVRS platform requires audio recording in *.wav format, so please record using Tape-a-talk which outputs *.wav format audio by default.
 
# Set frequency in the android app to 8,000GHz which is another requirement for IVRS.
 
# Hold your phone at exactly 45<sup>0</sup> degree angle and at half-feet distance from your mouth for better audio capture by phone's microphone.(Use earphones if available)
 
# Stop the recording when you are done and transfer audio file to your computer.
 
# Use Audocity to remove any noise from the audio file and export it to same *.wav format with 8,000GHz frequency.(Listen to your audio file in earphones if available)
 
# Use the exported audio file to send Voice SMS in the IVRS applciation.
 
  
 
[[Category:Ubuntu]]
 
[[Category:Ubuntu]]

Latest revision as of 17:46, 14 March 2019

ಕನ್ನಡದಲ್ಲಿ ನೋಡಿ

About

IVRS(Interactive Voice Response System) is commonly used platform to reach people connected through mobile/telephones. This page is about how one can set it up and send Voice SMS at any place with minimal requirements. In the school context we can us this software to communicate with parents easily. Most of our school parents are not capable to read sms or letters. from IVRS software we can reach all parents even if they are using basic mobile phones. From IVRS, schools can reach all parents easily by sending voice call. teachers can record their voice message and then send it through IVRS to parents mobile numbers. Same time parents will receive the call and they will hear their recorded message.

Installation and Deployment

This page helps anyone to deploy IVRS to send voice SMS from your Kalpavriksha(Ubuntu) machine with a data card. Call charges as per network would apply. Below instructions were modified from Mojolab site where this was used to install Swara software. This was tested on Kalpavriksha(Ubuntu) with Huwawei E173 and is currently used in Government High School, Domlur. An opensource IVRS program called Asterisk is used to run Swara software.

PleaseClick here to know detailed installation steps.


Please enter the given commands in terminal without any mistakes. After Installation completes please download VoiceBlast application from website. save this VoiceBlast file in Downloads folder on your computer. While processing with IVRS, we need to save our recorded audios and phone number list only in the folder.

Contexts

Parents Teachers Meetings

When schools are planning to have parent-teacher meeting at school to dicsuss strudents learning progress, attendance and ther issues, school can use IVRS to invite parents to this meeting. school can request parents through IVRS voice call to participate in Parent-Teacher meeting.
Examples:

  1. Ejipura IVRS Message to 8&9 students parents
  2. Ejipura IVRS Message to 10th students parents
  3. Tank Garden school IVRS Message to parents
  4. Agara school IVRS message to parents
  5. B.Agarahara School IVRS message to parents

School Level Programmes

Same like parent-teacher meeting school can also communicate parents about school level programmes like National festival celebration, Cultural activities, community meetings, anniversary programmes etc. It will encourage parents to attend school programmes.
Example:

  1. Adugodi school IVRS message to parents to attend school programme

Special Classes in School

In schools, for 10th students there will be regular special classess now. and its important to inform parents about special class timings. So that they will be aware about their children and it will help parents to send their children on early hours to school. Same information can send through IVRS voice calls to parents.
Example:

  1. Yediyuru school IVRS message to parents

Progress Card

School intention is to send progress card to home is to make parents awarded about their children progress. Most of the time students will not show their Progress card to parents and they will make parents signature instead of parents. In this context school can send a voice call through IVRS to inform about progress card issued and request them to see the progress and to make signature.and also school can request parents to meet class teachers if students progress is not good.

Irregular and Slow learn Students

If students are not attending classes regularly, most of the time parents may not aware about it. If school inform parents about their children absence, then parents can enquire and observe their children. and also school can make communication to parents about their children poor learning progress. and here school can insist parents to focus on their children reading at home. School can make list of Irregular and Slow learn Students and can send voice calls to those parents through IVRS.

For Example:

  1. Ejipura school IVRS message to parents
  2. Wilson Garden school IVRS message to parents
  3. Beguru school IVRS message to parents

To make reading at home

It will help students learning if parents are aware about their children education. They should always encourage children to engage in reading and writing at home. school can request parents to focus on their children reading /writing activities at home.

For Example

  1. Dommaluru school IVRS message-1 to parents
  2. Dommaluru school IVRS message-2 to parents
  3. Hombegowda high school IVRS message to parents
  4. Vijaya high school IVRS message-1 to parents
  5. Vijaya high school IVRS message-2 to parents about special classes
  6. MES high school IVRS message to parents
  7. Gangamma Hombegowda girls high school IVRS message to parents

School Admission

Schools may have several activities to increase school strength. One of the best idea is, they can contact nearby HPS schools and can get final class students database with parents contact numbers. By collecting parents contact numbers school can send voice calls to those parents and explaining about the facilities available in the school and can request them to admit their child to this our school.

Example:

  1. Dommaluru School IVRS message to HPS Parents.

Other Contexts

  1. School Level Programmes
  2. Community Programmes
  3. Health Camps
  4. School Trips
  5. Scholarship Distribution
  6. Exam Time Table anouncement
  7. School Holiday delcaration
  8. Sports activities

etc

Preparation to use IVRS

  1. Need to arrange a data card for school.Generally data cards has been used for internet purpose, but for IVRS we need to have voice call option with outgoing call facility. Internet is required only for IVRS installation and its not essential to run IVRS.
  2. Before sending voice calls, we need to think about message and context. its better to script the message.
  3. Scripted message can be recorded by using below steps:
    1. We can make voice record by desktop computers. but here head set/mike is compulsory to record. because desktop computers will not have direct input option. in Ubuntu computers we will use Audacity to record.
    2. Through laptops also we can record the voice, here we directly use the ubuntu technology "Audacity" to record the voice.To have good voice recording we must use mike or headsets.

Methods of recording on a computer or laptop

Be prepare with script and then record it in computer. To record we can use Audacity application in UBUNTU, to open audacity in your computer / laptop go to Application – Sound and Video – Audacity. then in that by pressing the record (red button) button you can start recording process. To save your recording go to FILE and then click on Export. Here while saving File Format must be .wav format. also select VoiceBlast folder from Downloads to keep this recording clip. And then click on Export, it will save in your computer.

NOTE : While recording the voice in Audacity the frequency must be set to 8000GHz . see the picture 1
And Audio input channel should 1.Mono input channel, to set this please go to menu bar and click on sterio drop down option, see the picture 2
1. 200px 2. 400px

Methods of recording on mobile

Be prepare with script and then record it in by your mobile phone. Normally in all android sets you will have Voice Recording option and you can use different applications also. In that “Tape-a-talk” application is most popular one and you can download this from your android playstore. In your mobile you can do Voice Recording by opening the application in silent area. Later you can transfer this recorded voice to computer. In computer through Audacity you can make changes to your recorded voice and you can save in .wav format and keep that in your computer or laptop in Downloads folder , in that VoiceBlast folder.
NOTE : NOTE : While recording the voice in Audacity the frequency must be set to 8000GHz.

Method to send IVRS recorded voice

  1. After completing voice recording, you can send recorded voice through IVRS .
  2. First you have to insert your data card to computer.
  3. Then go to Application > Office > IVRS 1.

Here you will see the running terminal.

  1. Again go to Application > Office > IVRS 2

After this, you will the picture of the window which you are seeing below. here you have to select the recorded voice list option, later select the phone numbers to whom you have to send the recorded voice. you can mention the duration of the recorded voice.It should be minimum of 15 seconds.
VoiceBlast.png

next click on SEND button. later you will see the progress of sending the voice in one of the terminal. in this you can see who all received the call. who have not received and even switched off numbers list also.