The OCXO option is an oven-controlled oscillator, thus providing a high accuracy frequency source: temperature characteristic: 5 * 10^-8 max, aging characteristic 10^-7 max./year.

The power supply provides power to the mobile phone under test: the current characteristics are similar to a proper battery, the power supply is sufficient for two time slots per frame, ready for GPRS, voltage level control through user interface, remote control or RAPID! programming language, open-ended power supply connection cable included.

The current measurement upgrade is complimentary to the power supply option and requires this option. The option provides an integrated current meter, e.g. to identify short-circuit situations, eases handling for the user. The 4400 user can test RF, audio and power consumption with one test instrument. Measurement possibilities: power, peak current and average current measurements, Numerical or graphical (current vs. time) representation of results. Statistical evaluation and overload detection.

4489 Bluetooth Connectivity Test Package

用于4400系列手机测试仪的4489测试包包括4941蓝牙连接测试硬件、可选的密钥以及对RAPID！评估测试脚本的少量修正（允许在正常测试过程中完成包括蓝牙在内的所有测试）。在打印以及存储到磁盘中的测试结果中将包括蓝牙测试结果。

1209 Downconverter

利用1209 Downconverter，待测设备的射频信号可以转换到4400支持的频率范围。从另一个方向来看，仪器的测试信号可以转换到不同的频率范围来激励待测手机的接收器。这样，利用仪器本身的信号发生器、功率计和频谱分析仪功能就可以完成手机中的无线LAN、GPS、蓝牙和移动TV收发器，不需要额外的测试设备，通常也不需要改变连接。