Shure LX88-II manual Tips for Getting the Best Performance, Troubleshooting, Specifications

TIPS FOR GETTING THE BEST PERFORMANCE

•Maintain a line-of-sight between the transmitter and receiver antennas.

•Keep the receiver and antennas away from large metal objects.

•Avoid placing the receiver near computers or other RF generating equipment.

•Point the antennas straight up.

•Avoid placing the receiver in the bottom of an equipment rack unless the an- tennas are remotely located.

•Use the proper receiver antennas. 1/4-wave antennas can be used if mounted directly on the receiver or front mounted on the rack ears using the WA503 Front Mount Conversion Kit; 1/2-wave or other ground-plane-dependent an- tennas must be used if antennas are remotely located.

TROUBLESHOOTING

Some common problems and their solutions are identified in the table below. If you are unable to solve a problem, contact your dealer.

Problem	Solution
No sound; RF light(s)	•Make sure the transmitter and receiver POWER
not glowing.	switches are ON.
	•Check battery.
	•Check receiver squelch setting.
	•Check receiver antenna connection(s).
	•Make sure antennas are in line of sight of
	transmitter.
No sound; RF and Audio Level	•Turn up receiver audio VOLUME control.
meter lights glowing.	•Check for proper connection between receiver
	and karaoke unit.
	•Talk into microphone and observe receiver audio
	level lights. If they glow, the problem is
	elsewhere in the sound system.
Received signal is noisy or con-	•Check battery.
tains extraneous sounds with	•Remove local sources of RF interference.
transmitter on.	•If using a guitar or other instrument, check
	connections.
	•Two transmitters may be operating on the same
	frequency. Locate and turn one off.
	•Signal may be too weak. Reposition antennas. If
	possible, move them closer to transmitter.
Noise from receiver with trans-	•Adjust receiver squelch control.
mitter off.	•Remove local sources of RF interference.
	•Reposition receiver or antennas.
Momentary loss of sound as	•Reposition receiver and perform another
transmitter is moved around per-	ªwalkthroughº test and observe the RF
forming area.	indicators. If audio dropouts persist, mark these
	ªdead spotsº in performing area and avoid them
	during performance.

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SPECIFICATIONS

RF Carrier Frequency Range

169.445 to 221.350 MHz

Working Range

100 m (approximately 300 ft) under typical conditions.

Audio Frequency Response

50 to 15,000 Hz, ±2 dB.

Audio Output Level (±15 kHz deviation, 1 kHz tone) XLR connector (into 600 Ω load): ±20 dBV (mic)

1/4±inch connector (into 3 kΩ load): ±8.8 dBV (Hi Z)

1/4 inch connector (into 3 kΩ load): ±18dBV (mix)

Gain Adjustment Range

LX1: 40 dB

LX2: 25 dB

Impedances

LX1 (input): 1 MΩ

LX88-II(output): 600 Ω (XLR); 5 kΩ (1/4-inch phone jack)

RF Power Output

LX1, LX2: 50 mW maximum (complies with FCC and IC regulations)

RF Sensitivity

±101 dBm, typical

Audio Polarity

Positive pressure on microphone diaphragm (or positive voltage applied to tip of WA302 phone plug) produces positive voltage on pin 2 with respect to pin 3 of low impedance output and tip of high impedance 1/4-inch output.

System Distortion (ref. ±15 kHz deviation, 1 kHz modulation) 0.7%

Power Requirements

LX1, LX2: 9V alkaline battery (Duracell MN1604 recommended). 8.4V Nicad (re- chargeable) are optional but not recommended.

LX88-II: 12 Vdc (PS20, 120Vac; PS20E, 230 Vac Power Supply)

Current Drain

LX1: 31 mA average (40 mA max), LX2: 30 mA average (35 mA max)

LX88-II: 160 mA average (195 mA max)

Operating Temperature Range

-20°to 50° C (-4°to 122° F). NOTE: Battery characteristics may limit this range.

Overall Dimensions

LX1: 82.6 mm H x 63.5 mm W x 26.2 mm D (31/4 x 21/2 x 11/32 in.)

LX2/58: 241 mm L x 50.8 mm Dia. (91/2 x 2 in.)

LX88-II: 44 mm H x 349 mm W x 194mm D (1 3/4 x 13 3/4 x 7 5/8 in)

Net Weight

LX1: 79.5 g (2.8 oz) without battery

LX2/58: 294.8 g (10.4 oz) without battery

LX88-II: 1.7 Kg (3.7 lbs)

Certification

LX1, LX2: Type-accepted under FCC Parts 90 and 74; IC certified under TRC-78

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