The Shure UA874US Active Directional Antenna is a professional UHF antenna designed to improve wireless microphone system performance by focusing reception toward the intended coverage area while rejecting unwanted RF signals.

Using a log-periodic dipole array, the UA874US produces a cardioid pickup pattern, providing stronger signal reception from transmitters positioned in front of the antenna and reducing interference from signals outside the coverage zone. This makes it ideal for large stages, conference venues, houses of worship, and broadcast environments.

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Shure UA874US Active Directional Antenna

The Shure UA874US Active Directional Antenna is a professional UHF antenna designed to improve wireless microphone system performance by focusing reception toward the intended coverage area while rejecting unwanted RF signals.

Using a log-periodic dipole array, the UA874US produces a cardioid pickup pattern, providing stronger signal reception from transmitters positioned in front of the antenna and reducing interference from signals outside the coverage zone. This makes it ideal for large stages, conference venues, houses of worship, and broadcast environments.

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Improved Wireless Signal Reception

Unlike standard omnidirectional antennas, the UA874US concentrates its reception pattern toward the target area, helping maintain stable wireless connections and reducing dropouts.

Key RF performance benefits include:

• Directional cardioid pickup pattern
• Improved rejection of unwanted RF signals
• Enhanced reception for wireless transmitters
• Better signal stability in crowded RF environments

This makes the antenna especially useful in installations where wireless receivers must be positioned away from the stage or performance area.

Integrated Low-Noise RF Amplifier

The UA874US includes a built-in low-noise signal amplifier with four selectable gain settings, allowing the antenna to compensate for signal loss caused by long coaxial cable runs.

Gain settings allow integrators to optimize performance depending on cable length and system layout.

Benefits include:

• Compensation for coaxial cable transmission loss
• Improved signal integrity
• Optimized RF performance for complex installations

Flexible Mounting Options

The UA874US is designed for versatile installation and can be mounted in several ways:

• Microphone stand mounting
• Wall mounting
• Ceiling suspension

A swivel adapter bracket is included, allowing the antenna to be aimed precisely at the wireless coverage area.

This flexibility allows the antenna to be positioned for optimal RF performance in live venues, auditoriums, and production environments.

Designed for Professional Wireless Systems

The UA874US works with Shure wireless receivers and antenna distribution systems that provide DC bias power. It is commonly used with systems such as:

• Shure ULX-D
• Shure QLX-D
• Shure SLX-D
• Shure Axient systems
• Other compatible RF distribution systems

The antenna is widely used in professional environments where reliable wireless performance is critical.

Shure UA874US Key Features

• Active directional RF antenna for wireless microphone systems
• Log-periodic dipole array design
• Cardioid pickup pattern improves RF coverage
• Rejects unwanted RF signals outside coverage area
• Integrated low-noise amplifier
• Four-position gain selector
• Compensates for coaxial cable signal loss
• Compatible with Shure wireless receivers and antenna distribution systems
• Stand, wall, or ceiling mounting options
• Swivel adapter bracket included

Typical Applications

The Shure UA874US is ideal for:

• Live sound systems
• Concert stages
• Broadcast studios
• Houses of worship
• Corporate AV installations
• theaters and performance venues
• conference centers
• touring wireless systems

Technical Overview

Antenna Type
Active directional log-periodic dipole array

Polar Pattern
Cardioid directional coverage

Gain Settings
Selectable RF gain levels to compensate for cable loss

Mounting Options

• Microphone stand mounting
• Wall mounting
• Ceiling suspension

Power

• Powered via DC bias from wireless receiver or antenna distribution system