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Lectrosonics IFBT4 Frequency-Agile IFB Transmitter (Frequency Block 21)

B&H # LEIFBT421 MFR # IFBT4-21
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You Pay: $845.00
Product Highlights
  • Dual Hybrid Wireless Technology
  • XLR Input
  • Backlit LCD
  • Aluminum Construction

The IFBT4 from Lectrosonics is a high-quality IFB transmitter designed for applications where long operating range and great audio quality are needed, such as broadcasting, film, and theater. The sleek, simple box can be used as a stand-alone unit, or patched into other widely-used intercom systems. The single XLR input connector is accompanied by four DIP-switches for selecting a mic, line, Clear Com, RTS1, or RTS2 audio source.

The Digital Hybrid Wireless technology allows the system to overcome channel noise by digital encoding and decoding audio in the transmitter and receiver, but sending the encoded signal over an analog FM signal. Due to the FM link being used, the system has all the benefits of traditional FM systems, including high range and resistance to interference, but thanks to the digital technology, the analog compander and artifacts are removed for greater audio quality.

The system is easy to use, featuring a menu-based, microprocessor-controlled system that is navigated with momentary buttons. The backlit LCD is bright and clear for easy reading. The casing is constructed from rugged aluminum to withstand the rigors of professional use, and it is small enough to use in any situation.

Sleek, easy to use IFB transmitter with long range, terrific audio, and low distortion
Digital Hybrid Wireless technology combines digital and analog technologies to reap the benefits of both
Choose from 256 UHF frequencies in 100kHz steps
Microprocessor-controlled with easy-to-use menu-based navigation
Standard 3-pin XLR jack can accept mic, line, Clear Com, RTS1, and RTS2 signals
Output power of 250mW for long range transmission, BNC antenna included
Built-in mic preamp
Pilot tone squelch control
Frequency scrolling with Tx mute
Easy-to-read LCD Display
Compact and rugged aluminum housing
Operating Frequency 537.6 to 563.1 MHz
Frequencies 256 Channels Per Block
Channel Spacing 100 kHz
Spurious and Harmonic Suppression 37 dBc Above 1 GHz
Frequency Stability ±0.001% (10 ppm) @ 77°F (25°C)
Temperature Stability ±0.001% (10 ppm) @ -22 to 122°F (-30 to +50°C)
Compatibility Modes IFB, Digital Hybrid Wireless (400 Series), 100 Series, 200 Series, Mode 3, Mode 6
Pilot Tone 29.997 kHz IFB Mode, 32.765kHz 200 Mode, 400 Mode Step Selected, 32.768 kHz Mode 6
Modulation FM, ±20 kHz Deviation IFB & 100 Mode, ±75 kHz 200 & 400 Mode, ±50 kHz Mode 3 and Mode 6
Audio Frequency Response 100 Hz - 8 kHz, ±1 dB IFB Mode
30 Hz - 20 kHz, ±1 dB 200 & 400 Mode
Low Frequency Roll-Off 3 dB Down @ 35 or 50 Hz, Menu Selectable
Signal to Noise Ratio 90 dB Typical, A-Weighted
RF Power Output 250 mW, Nominal
Output Impedance 50 Ohms
Audio Input Level Line, RTS1, RTS2: 0 dBu
Clear Com: -10 dBu
Mic Dry Inputs: -42 dBu
Audio Input Impedance Balanced: Greater than 2 kOhms
Unbalanced: Greater than 1 kOhm
Gain -18 to +24 dB, Software Selectable
Connectors 1 x XLR Input Connector
1 x BNC Antenna Connector
1 x DC Power Input
Controls and Indicators 4 x Mode Switches (For Selecting Type of Input Source)
1 x Menu Button
2 x Select Buttons (Up/Down)
1 x Off/Tune/Xmit Switch
1 x Backlit LCD Display
Power 12-14 VDC, Typical, 200 mA Max
Dimensions (LxWxH) 5.25 x 3.25 x 1.25" (133 x 83 x 32 mm)
Weight 9 oz (255 g)
Lectrosonics IFBT4 Frequency-Agile IFB Transmitter (Frequency Block 21)
  • Antenna
  • AC Adapter
  • Owner's Manual
  • 1-Year Limited Warranty
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