Shure UA874V – Active Directional Antenna for VHF 174–216 MHz

Product Overview

The Shure UA874V is an active directional antenna for Shure VHF wireless systems operating in the 174–216 MHz frequency range. Using a log periodic dipole array, it delivers 7.5 dBi on-axis gain with a 70° beam width and four switchable gain positions, providing the active antenna infrastructure needed to extend VHF wireless coverage in commercial AV deployments where receiver-mounted whip antennas are insufficient. For integrators managing VHF-band Shure wireless systems in fixed commercial installations, the UA874V is the purpose-built active directional solution for this frequency range.

Product Description

Many commercial environments — conference centers, government facilities, educational institutions, and houses of worship — operate Shure VHF wireless systems that require remote antenna placement for adequate RF coverage of the space. The UA874V addresses this need with a log periodic dipole array that focuses reception toward the intended coverage area while actively amplifying the received signal to compensate for coaxial cable run loss. The four-position gain switch allows the installer to precisely dial in the gain needed for the specific cable length, avoiding the system degradation caused by excessive amplification. The integrated swivel adapter supports mounting on microphone stands, ceilings, or walls, providing flexibility for diverse commercial installation configurations. DC bias power (10–15 V at 75 mA) is required through the coaxial cable from the connected receiver or antenna distribution system. For large VHF wireless systems requiring antenna distribution, the UA874V connects to the Shure UA845UWB Antenna Distribution System, which covers the VHF band. For passive VHF omnidirectional coverage, see the Shure UA860V Omnidirectional VHF Antenna.

Key Features

• Log Periodic Dipole Array for VHF (174–216 MHz) — Provides a cardioid-pattern directional reception characteristic tuned to the 174–216 MHz VHF band, improving signal capture from VHF wireless transmitters while rejecting off-axis interference.
• 7.5 dBi On-Axis Antenna Gain — Delivers 7.5 dBi of antenna gain in the beam direction, providing substantial signal margin over passive or omnidirectional alternatives in commercial VHF wireless installations.
• 70° 3 dB Beam Width — A 70-degree beam provides practical directional coverage for commercial room installations without requiring highly precise antenna aiming during deployment.
• 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) to compensate precisely for coaxial cable loss in commercial AV installations.
• Integrated Swivel Mount Adapter — Supports stand, ceiling, or wall mounting without additional hardware, providing commercial installation flexibility.
• Active Amplification with DC Bias — Integrated amplifier compensates for coaxial cable insertion loss; powered via 10–15 V DC bias from the connected receiver or distribution system through the coaxial cable.
• RF Overload LED Indicator — Visual alert when the amplifier is being overloaded by excessive RF signal strength, helping technicians properly configure gain settings during system commissioning.

Typical Applications

• Conference room
• Boardroom
• Government space
• House of worship
• Training room
• Commercial meeting space
• Multi-purpose room
• Auditorium

Technical Specifications

Frequently Asked Questions

Does the UA874V require power?
Yes. The UA874V requires 10–15 V DC bias at 75 mA through the coaxial cable from a compatible Shure wireless receiver or antenna distribution system. It will not operate without this bias voltage, including at the −6 dB and 0 dB passive gain settings.

What Shure VHF wireless systems is the UA874V compatible with?
The UA874V is designed for Shure wireless systems operating in the 174–216 MHz VHF frequency range. Confirm your specific system’s frequency band assignment before ordering to ensure compatibility.

When should I use the UA874V instead of the UA860V?
Use the UA874V when coverage needs to be directed toward a specific area (stage, podium, front of room) and when the antenna cable run requires active gain compensation. The UA860V is a passive omnidirectional antenna suited for spaces where transmitters move freely and cable runs are short enough not to require amplification.

Is the UA874V compatible with antenna distribution systems?
Yes. The UA874V connects to compatible Shure antenna distribution systems such as the UA845UWB, which covers the VHF frequency range, enabling one or two UA874V antennas to serve multiple VHF wireless receivers simultaneously.

Can the UA874V be permanently installed?
Yes. The integrated swivel adapter supports permanent mounting on stands, ceilings, or walls. Do not install the UA874V in permanent outdoor locations or environments subject to extreme moisture.