Wireless IFB (interruptible fold back) systems are used for talent cueing and crew communications in broadcast and motion picture production
In other cases, the IFB system is used by directors and other management to monitor program audio during a production. The IFBR1B receiver provides simplicity and flexibility in a package that is intui- tive for untrained users to operate. In spite of its tiny size, the new IFBR1B receiver offers excellent performance on par with all of Lectrosonics' IFB products.
The design uses +/-20 kHz FM deviation for efficient use of the bandwidth, with compandor noise reduction circuit- ry for an excellent signal to noise ratio. A supersonic Pilot Tone signal controls the audio output squelch to keep the receiver silent when no transmitter signal is received. The incoming RF signal is filtered and amplified, then mixed down to the IF frequency with a microprocessor controlled synthesizer.
If a monaural earpiece is connected, this condition is automatically accommodated, with no loss of audio output power or battery life. Full output power is available with either type of connector, without the power losses that re- sult from a resistive circuit design. The headphone cable doubles as the receiving antenna.
The receiver will drive a wide variety of earbuds, head- phones and induction neck loops at substantial levels, with loads from 16 Ohms to 600 Ohms.
High sensitivity for extended operating range indoors or outdoors
USB port for firmware updates
Compact, rugged machined aluminum housing
Attached battery door
8+ hours battery life with removable LB-50 Li-ion
Dock chargeable with optional CHSIFBR1B
Pilot tone squelch
Compandor noise reduction
Spécifications
Frequency Selection Steps: Sensitivity: 25 kHz or 100 kHz, selectable; VHF: 125 kHz
Signal/Noise ratio: 95 dB A-weighted
Squelch quieting: 90 dB
AM rejection: 50 dB, 10 uV to 100 mV
Modulation acceptance: ±20 kHz
Spurious rejection: Greater than 70 dB
Operating temperature range: -20 to 45 degrees C.
Third order intercept: 0 dBm
Frequency response: 100 Hz to 10 kHz, (+/-1 dB)
Audio output: 1V RMS into 50 ohms minimum
Antenna: Headphone cable
Min. headphone impedance: 16.0 Ohms
Programmable memory: 10 frequencies can be stored as presets
Controls:
Top Panel: Single knob controls Audio Output Level and Power On Side Panel: Membrane switches with LCD interface for Frequency, Selection and Preset function
Indicators: Multi-color LED indicator for power on and battery status
Battery: LB-50 Li-ion 3.6 V 1000 mAH
Battery Life: 8 hours per charge with LB-50 Li-ion battery