The Lectrosonics IFBT4 instruction manual provides setup, operation, and specifications for the synthesized UHF IFB transmitter.
The Lectrosonics IFBT4 is a synthesized UHF IFB transmitter that delivers digital‑hybrid wireless audio with a backlit LCD display and flexible frequency selection.
This manual details hardware installation, audio input configuration, frequency tuning, power requirements, antenna setup, panel controls, and troubleshooting procedures.
| Power Input Voltage | 6‑18 VDC |
|---|---|
| Power Input Current | 200 mA max |
| RF Output Power | 250 mW |
| Frequency Channels | 256 frequencies, 100 kHz steps, 25.6 MHz band |
| Audio Input Gain Range | -18 dB to +24 dB |
| Low‑Frequency Roll‑off Settings | 35 Hz or 50 Hz (default 50 Hz) |
| Antenna Type | Right‑angle ¼‑wave monopole with BNC connector |
The IFBT4 can be powered from any external DC source of 6 to 18 V at up to 200 mA, or from the supplied 12 V power supply.
The transmitter can tune to 256 different frequencies in 100 kHz steps within a 25.6 MHz block.
Press and hold the MENU button for about 4 seconds; a progress bar appears and the unit toggles between locked and unlocked states.
The default roll‑off setting is 50 Hz, which helps reduce wind and rumble.