Shure PA421B Four-channel Antenna Combiner, 470-865 MHz

The PA421B is a professional-grade antenna combiner designed to simplify multi-channel wireless in-ear monitoring (IEM) systems. It allows up to four wireless transmitters to share a single antenna, reducing intermodulation distortion and minimizing the number of antennas required in a setup. This results in improved RF performance, cleaner signal transmission, and a more organized stage or rack configuration. Built for reliability, it is well-suited for touring, live sound, and broadcast environments.

Features:

• Combines up to four wireless transmitter signals into a single antenna output

• Wide frequency range: 470–865 MHz for compatibility with various wireless systems

• Reduces intermodulation artifacts for clearer RF performance

• Internal power supply distributes DC power to connected transmitters

• Front-panel LED indicators for power and signal status monitoring

• RF input and output connectors designed for secure, stable connections

• Rack-mountable design for easy integration into professional setups