Shure UA874WB – Wideband Active Directional Antenna 470–900 MHz

Product Overview

The Shure UA874WB is a wideband active directional antenna covering 470–900 MHz, designed to improve UHF wireless microphone system reception in commercial AV deployments. Using a log periodic dipole array, it delivers 7.5 dBi on-axis gain with a 70° 3 dB beam width, and a four-position switchable gain setting (−6 dB to +12 dB) allows the installer to compensate precisely for varying cable run lengths. The UA874WB’s broad frequency coverage makes it compatible with a wide range of Shure UHF wireless products across the 470–900 MHz range, including systems used in commercial conference, broadcast, and live production environments.

Product Description

Active directional antennas are the preferred choice in commercial wireless installations where coverage needs to be concentrated toward a defined area — a stage, podium, or meeting room — while rejecting RF interference arriving from other directions. The UA874WB’s log periodic dipole array provides a cardioid-like directional pattern aimed toward the coverage zone, combined with active amplification to recover signal lost in antenna cable runs. The four-position gain switch is calibrated to common cable loss scenarios, giving integrators direct control over the total RF path gain budget without requiring spectrum analyzer measurements during installation. The integrated swivel adapter enables mounting on a microphone stand, ceiling mount, or wall bracket, offering flexibility for diverse commercial installation types. Power is supplied via DC bias through the coaxial cable from a compatible receiver or antenna distribution system — the UA874WB requires 10–15 V DC bias at 75 mA and will not operate without it. For large multi-channel installations, the UA874WB pairs well with the Shure UA845UWB Antenna Distribution System.

Key Features

• Log Periodic Dipole Array — Provides a directional cardioid-pattern receive characteristic aimed toward the coverage area, improving desired signal reception while rejecting off-axis RF interference in commercial wireless environments.
• 7.5 dBi On-Axis Antenna Gain — Delivers 7.5 dBi of antenna gain in the beam direction, significantly improving signal margin over passive omnidirectional antennas in longer-range or interference-prone commercial deployments.
• 70° 3 dB Beam Width — The 70-degree beam provides a practical coverage angle for most commercial room installations without requiring extremely precise aiming.
• Four-Position Switchable Signal Gain (−6 to +12 dB) — Adjustable in nominal steps of +12 dB, +6 dB, 0 dB, and −6 dB (±1 dB), allowing precise compensation for coaxial cable run loss in commercial AV installations with varying cable lengths.
• Wideband 470–900 MHz Coverage — Covers the majority of commercial UHF wireless frequency bands in a single antenna, compatible with Shure wireless systems operating in this range.
• Integrated Swivel Adapter — Built-in swivel adapter enables mounting on microphone stands, ceilings, or walls without additional mounting hardware, accommodating diverse commercial installation types.
• RF Overload LED Indicator — Integrated LED indicates when the antenna amplifier is receiving an excessively strong RF signal, helping technicians adjust gain settings and transmitter distance for optimal system performance.
• BNC Female Connector, 50 Ω — Industry-standard BNC termination at 50 Ω impedance connects directly to Shure wireless receivers and antenna distribution systems.

Typical Applications

• Conference room
• Boardroom
• House of worship
• Government space
• Broadcast studio
• Auditorium
• Training room
• Multi-purpose room

Technical Specifications

Frequently Asked Questions

Does the UA874WB require a power supply?
Yes. The UA874WB requires 10–15 V DC bias at 75 mA supplied through the coaxial cable from a compatible Shure wireless receiver or antenna distribution system. The antenna will not operate without this bias voltage, including at the −6 dB and 0 dB gain settings.

How should I set the gain on the UA874WB?
Set the gain to compensate for calculated coaxial cable signal loss only. Use the cable manufacturer’s loss specification to calculate the expected loss for your cable length and type, then select the gain setting closest to that value. Adding excess gain degrades rather than improves system performance by amplifying noise and RF interference.

Can the UA874WB be used with Shure Axient Digital systems?
Yes, provided the Axient Digital system operates within the 470–900 MHz frequency range covered by the UA874WB and the connected receiver or distribution system supplies the required DC bias.

What is the difference between the UA874WB and the UA860SWB for commercial installations?
The UA874WB is an active directional antenna with 7.5 dBi gain and a 70° beam, suited for installations where coverage needs to be focused on a defined area (stage, podium, presentation zone). The UA860SWB is a passive omnidirectional antenna providing 360° coverage, suited for spaces where transmitters move freely without a defined coverage zone.

Is the UA874WB suitable for permanent commercial installation?
Yes. The UA874WB can be permanently mounted on a microphone stand, ceiling, or wall using the integrated swivel adapter. It should not be used in permanent outdoor installations or exposed to extreme moisture.