R300-L Lapel System - ULM18 Directional Microphone by Electro-Voice
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Lapel System - ULM18 Directional Microphone

  • R300-L
  • R300-L
  • R300-L
The R300-L is a robust UHF wireless bodypack system, suitable for any application where the convenience of a wireless lavalier microphone is required. The system's BP-300 rugged metal bodypack transmitter is simple to use, and is powered by two AA batteries. Included with the system, the ULM18 is a high quality directional (cardioid) condenser lavalier microphone suitable for sound reinforcement or recording of voice, and allows users the convenience of a hands-free presentation or performance experience. Exceptionally useful for sound reinforcement applications, the ULM18’s directional cardioid polar pattern reduces sound system feedback potential when used properly. The receiver's dual antenna diversity helps avoid signal dropouts, and its durable metal frame and chassis can either be used on a tabletop, or rack-mounted with optional rack mounting hardware.  Visit the R300 microsite
Frequency Band Estimator
  • ClearScan automatically finds the clearest channel
  • EZsync one-step channel setup
  • ULM18 directional lavalier microphone
  • 14 hour battery life from two AA alkaline
  • Rugged metal transmitter
  • Metal receiver chassis with optional rack mount
Antennas Flexible TNC 1/2 Wave
Audio Frequency Response 80 Hz - 18kHz +/- 2dB
Balanced Line Level Output (RMS Adjustable) 10 - 100 mV
Battery Life 14 Hours with (2) AA alkalines typical
Case Material Metal
Connector Type 1/4 inch unbalanced, 3-Pin XLR balanced
Controls On/Off, Set, Up, Down, Sync
Distortion (@ 1 kHz, 40 kHz deviation) less than 1.0, 0.4 typical %
Diversity True Antenna
Dynamic Range greater than 95 dB dB
Element ULM18 Directional Microphone
Number of Channels 32 Per Band, 8 Simultaneous
Operating Temperature Range 5º - 45º C (41º - 113º F)
Power Requirement 12-16 VDC, 500 mA max
Power Supply 12 VDC, 500 mA max
Receiver Type Synthesized PLL
RF Frequency Range 16 MHz
RF Output 8 mW Typical
RF Sensitivity (12 dB SINAD) less than 1.0 uV
Signal-to-Noise Ratio (A-weighted) greater than 100 dB dB
Squelch Tone code plus Amplitude


Antenna for R300 Receiver

R300 Systems are available in the following bandwidths. The from and to frequency numbers shown below represent the lower and upper limits of the system tuning bandwidth.

Frequency Spread NTSC TV Channel Orientation
Band From To Lower (from) Upper (to)
A 618.000 MHz 634.000 MHz 38 41
B 678.000 MHz 694.000 MHz 48 51
C 516.000 MHz 532.000 MHz 21 24

Selecting the proper system tuning bandwidth for your local area is very important to successful wireless microphone system performance. Please make sure to use our automated frequency band selector to help in choosing the most appropriate bandwidth for your area.
Use the Frequency Band Selector

Optional accessories
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