There are multiple versions and variants of VoiceCallsTest-AudioFeedback.sh for different network speeds. Each one will start a phone call and keep it active for a user specified time, until the call fails, or until another varying condition is met.
The following is a description and changelog for the 3G variant, version 20. Email addresses have been redacted.
#########################
## ScriptName: 3GVoiceCallsTest.sh
## Usage: ./3GCallsOnly.sh {iterations to run} {Max_Length_of_Calls_in_minutes,0=NO LIMT}
## Purpose: To make calls on 3G and keep them active till either a call drop happens or
## the device hands over to 2G, keep call active for 30 seconds after HO to ensure that
## the HO succeeded.
## Length of call can be user specified in minutes or 48 hours if given as 0 minutes
## (in other words, till a call drop happens or 2 days have gone by without a drop)
## After every iteration check whether the device is still on 3G or not, otherwise
## try forcing 3G by going in/out of Airplane mode.
## Author: Puneet Mishra
## Revision History
## 06/22/2008 xxxxxxx@apple.com First Version
## 06/24/2008 xxxxxxx@apple.com Added function to take a K00LSTATE, not being used but can be invoked by removing
## the comment after the call passes, logs are overwritten after taking 20 logs hence
## be careful when using this.
## 06/30/2008 Added logCallEndedDate(), this will log time in CFGetAbsoluteTime format(in seconds from
## 1 Jan 2000 00:00:00) to callended.txt, this file will be used to generate .kml files for viewing
## call drop locations on a map
## 07/10/2008 Device does not go into airplane mode anymore for performing reselections
## Added a command which will make sure that unwanted dialogs from the network are dismissed before attempting UI operations
## e.g. notifications from the network about account stats for post-paid SIMs
## 09/08/2008 xxxxxxx@apple.com
## - Wait for 45 seconds after HO to 2G instead of 60 seconds
## - In the csv file that is generated, note whether the call drop was :Ê
## a. In 3G
## b. within 15 seconds of a HO
## c. After 30 seconds of H
## 09/09/2008 xxxxxxx@apple.com
## - Added call drop category in csv file
## d. Call Failure
## 09/10/2008 jerome jesu zzzzzz@apple.com
## -- Added Modem Resets, Call Drops and Call Failures breakdowns from CSI Logs
## -- Added Cause Codes for Call Failure/Call Drops to a separate CSV File
## 10/09/2008 jerome jesu zzzzzz@apple.com
## -- Fixed Modem Reset Column and added support for the AP Change.
##################################################