Shure UA874 manual Active Directional Antenna General Description, Installation, Interface

Active Directional Antenna

General Description

The Shure UA874 uses a log periodic dipole array to offer enhanced re- ception when directed toward the desired coverage area. An integrated amplifier and four gain settings compensate for varying degrees of coaxial cable signal loss. The UA874 can be mounted on a microphone stand, suspended from the ceiling, or mounted to a wall using the integrated swivel adapter bracket.

Features

•Low-noise signal amplifier compensates for insertion loss in coaxial cable

•Compatible with Shure wireless receivers and antenna distribution systems that provide 10–15 V DC bias

•Integrated threaded adapter mounts easily to microphone stands

•Four-position gain selector switch

•Shure quality, ruggedness, and reliability

Installation

•Connect the antenna to the receiver or distribution system using Shure antenna cables (or any 50 ohm, low-loss coaxial cable, such as RG-8U).

•The antenna only operates with receivers or distribution systems that provide 10–15 V DC bias.

•Lower the gain setting for short cable runs, or increase gain for longer runs. Note that the quality of the cable, not just the length, contributes to signal loss. A lighter-grade 50 foot cable may require more gain than a 100 foot, low-loss cable. Contact the cable manufacturer for cable loss specifications.

•Direct the antenna toward the intended coverage area.

•Do not use this antenna for transmitting (such as with PSM transmitters)

Cable Maintenance

To maintain top performance for UA825, UA850 or UA8100 antenna cables:

•Avoid sharp bends or kinks in the cables.

•Do not deform cables with makeshift clamps, such as bending a nail over the cable.

•Do not use in permanent outdoor installations.

•Do not expose to extreme moisture.

Antenna Cables from Shure

Shure offers the following pre-terminated antenna cables:

Length	Type	Model No.
6 foot	RG58	UA806
10 foot	RG58	PA725
25 foot	RG8X	UA825
50 foot	RG213	UA850
100 foot	RG213	UA8100

Interface

①Gain Switch

Adjust the four-position gain switch to compensate for the calculated cable loss, based on the length and type of cable.

Caution: There may be a small RF dropout when changing the gain setting.

②Gain Mode LED

Indicates the current gain switch setting.

③RF Overload LED

Indicates a strong RF signal that is overloading the antenna amplifier, which results in distortion or poor performance. Increase the distance between the antenna and transmitter, or lower the antenna gain setting.

NOTE: RF Overload LED does not operate for passive gain settings (−6 dB or 0 dB).

④BNC Connector

Connect to a reciever or antenna combiner with RF inputs that supply 10–15 V DC bias.

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