Shure UA870 - Manual

MODEL UA870 UHF ACTIVE DIRECTIONAL ANTENNA

The Shure UA870 is an active UHF wireless directional anten-

na. It features a log periodic dipole array. When compared to an om-

nidirectional 1/2-wave antenna, the cardioid pattern provided by the

UA870 offers enhanced reception of the desired coverage area and

greater rejection of RF signals outside the coverage area.

To compensate for coaxial cable signal loss, the UA870 has an

on-board amplifier that offers user selectable 3 or 10 dB gain. The

gain setting is indicated by two LEDs. Remote 12 Vdc power for the

antenna amplifier is provided by a Shure U4 or ULX Receiver or a

Shure UA845 or UA844 Antenna Distribution System through the

connecting coaxial cable.

The UA870 can be mounted on a microphone stand, sus-

pended from the ceiling, or mounted to a wall using the integrated

swivel adapter bracket. The UA870 is weather resistant for use out-

doors. For best diversity performance, use two UA870 antennas.

INSTALLATION INSTRUCTIONS

1. Determine the length of cable required to connect the UA870

Antenna to the U4 or ULX Receiver or UA845 or UA844 Anten-

na Distribution System.

IMPORTANT:

Always use low-loss 50 ohm cable, such as RG-8X or equiva-

lent. Shure UA825 7.6 m (25 ft.) or UA850 15.2 m (50 ft.) or

UA8100 30.4 m (100 ft) cables are recommended.

2. Set the gain switch to the appropriate setting. If you are using

coaxial cables up to 7.6 m (25 ft.) long, select the 3 dB posi-

tion. If using cables 7.6 m (25 ft.) or longer, select the 10 dB

position. To access the gain switch, remove the cover of the

preamplifier box (printed side) by unscrewing the four screws

at each corner. Gain settings are marked on the pc board in-

side.

NOTE:

The UA870 gain control is factory preset at the 10 dB

position.

3. Connect one end of the antenna cable to the UA870. Then

mount the antenna so that it points toward the intended cover-

age area. See Figure 1.

4. Connect the other end of the antenna cable to the U4 or ULX

Receiver or UA845 or UA844 Antenna Distribution System.

The gain LED on the UA870 illuminates to verify that power

is being provided to the antenna.

IMPORTANT:

Always perform a “walk around” test to verify coverage be-

fore using a wireless system during a speech or perfor-

mance. Experiment with antenna placement to find the opti-

mum location for the UA870.

FIGURE 1

NOTE:

For additional technical assistance, call the Shure

Customer Service Department at 1-800-434-3350. In Europe,

phone 49-7131-72140.

SPECIFICATIONS

RF Frequency Range

UA870A

782-810 MHz

. . . . . . . . . . . . . . . . . . . . . . .

UA870KK

838-862 MHz

. . . . . . . . . . . . . . . . . . . . .

UA870MB

800-830 MHz

. . . . . . . . . . . . . . . . . . . . .

UA870MC

774-782 MHz

. . . . . . . . . . . . . . . . . . . . .

UA870UB

692-716 MHz

. . . . . . . . . . . . . . . . . . . . .

UA870WB

470-900 MHz

. . . . . . . . . . . . . . . . . . . . .

Power Source

Remote 12 Vdc from coaxial cable connection to receiver or

antenna distribution system.

Power Consumption

UA870 (A, KK, MB, MC, UB):

0.81 W (12 Vdc)

UA870WB: .68W (12Vdc)

Antenna Gain

7 dB typical (on axis)

Amplifier Gain

UA870 (A, KK, MB, MC, UB):

Gain Switch at 3 dB: 3 dB

±

2 dB

Gain Switch at 10 dB: 10 dB

±

2 dB

UA870WB: Gain Switch at 3 dB (–2, +1.5 dB)

Gain Switch at 10 dB (–1 dB, +3.0 dB)

Third Order Intercept Point

(3OIP) at output

More than 30 dBm

Reception Pattern

Directional; Cardioid

3dB Beam Width: 100 degrees

Model UA870 UHF Active Directional Antenna

User Guide

27C8629 (C

A

)



2003, Shure Incorporated

Printed in U.S.A.