Ergonomically shaped test phone for the installation and maintenance of voice services on analog lines. The device operates without a battery, as it is powered through the telephone line, and features a high-impedance monitor that is data and DSL safe. Polarity testing, speed dialing, and pulse dialing are included in the performance range. The included headset allows for hands-free operation. The TM-500 provides safety through overvoltage and overcurrent indication.