TRX742 Transmitter for Boom

The TRX742 is a plug-on style digital wireless microphone with interchangeable cones to support all professional microphone varieties – mono analog, stereo analog, AES and AES42 – making it an ideal choice for wireless transmission directly from boom poles or handheld microphones.

TRX742 comes standard with a built-in backup recorder, timecode reader / generator and the ability to receive timecode and remote control commands via the IFB100, Nomad, and/or ZaxNet.  Its body is constructed from a combination of high strength nylon polymer and aluminum.



TRX742 Boom Transmitter

Key Features:

  • NeverClip™ with 127 dB dynamic range
  • Built-in 2.4 GHz receiver, receives timecode and remote control signals from ZaxNet and/or the IFB100
  • 96 hour internal backup recording with timecode stamp
  • Digital modulation wireless transmission
  • Superb audio quality that rivals a mic cable
  • Mono or Stereo transmission
  • Variable power output, up to125 mW
  • ZaxNet remote controllable
  • 48 V phantom power



TRX742 Overview:

The TRX742 is powered by 3 AA batteries.  The power output is user selectable at 25, 50 or 125mW.   If you are in a country where it is illegal to use anything above 50 mW, your dealer will notify us at the time of ordering.  The TRX742 can utilize the battery saving feature PowerRoll™ (part of ZaxNet).  PowerRoll™ automatically adjusts the transmitter output power based on the record status as sent via ZaxNet boosting it up to 125 mW while rolling and powering down to 50 mW while on standby.

They feature 100% digital transmission for audio quality that rivals a hard-wired system and are fully encrypted to eliminate the possibility of production audio interception and theft.  They come standard with our patented internal timecode referenced back-up recorder which backs up the transmitted audio onto a removable microSD card eliminating the possibility of audio loss due to interference or signal dropout.  They and are fully compatible with all Zaxcom wireless receivers and IFB transmitters.

The TRX742 works with ZaxNet, Zaxcom’s 2.4-GHz RF network that enables the distribution of remote control signals, timecode, IFB audio, and metadata. With ZaxNet, one can remotely control gain settings and replay audio via a timecode reference giving production sound mixers the ability to replay and remix audio, creating a virtual multi-track playback and re-record system.

The TRX742 is easily converted from 3-pin XLR female connection to 5-pin stereo XLR stereo operation with a plug on XLR assembly.  The XLR cones are easily swapped in the field for ultimate flexibility.

NeverClip (Patent Pending) is a dual A-D preamp system that provides extended dynamic range of 127 dB.  NeverClip combined with Zaxcom’s soft knee compressor and digital hard wire quality transmission provides a level of audio quality not found in any other plug on transmitter.


More on Internal Recording

The TRX742’s 96 hour, 24 bit internal recording is perfect for those times when there’s a lack of available frequencies or when drop-outs cannot be tolerated.  The audio is timecode referenced, recorded on and played back from a removable MicroSD memory card that can be used in any standard SD card reader.

Audio can be recorded, played back and timecode referenced either manually or through remote control commands from the IFB100 transmitter or ZaxNet.

The audio is automatically recorded full bandwidth as a .ZAX file. The included ZaxConvert file transfer software (available for both MAC and PC) utilizes sample rate conversion to obtain the sample rate and bit depth of choice when files are imported to your computer. There are two timecode stamped file types to choose from: BWF (Broadcast Wave Format) or MP3 (MPEG-1 Audio Layer 3). MP3 files are great for quickly transferring files over the internet to a transcription house. Any number of versions of the same recording can be made from a single file.

TRX742 comes standard with the cone of your choice, extra cones can be purchased as accessories.

Cone choices:

♦Mono Analog – 3-Pin XLR
♦Stereo Analog – 5-Pin XLR
♦AES (not powered) – 3-Pin XLR
♦AES42 (powered) – 3-Pin XLR


TRX742 Specifications


Power output: 25 / 50 / 125 mW – Software Selectable (10 mW special order)
RF Modulation: Proprietary Digital Method
RF Frequency Range: 518.0 to 872 MHz (typical blocks are 35 MHz)
RF Frequency Step: 100 KHz
RF Bandwidth: 200 KHz
Channel Separation: 500 KHz (700 KHz recommended)
Antenna Connector: 50 Ω SMA Female
Emission Designator: 180 KV2E
FCC Part: 75.861.

Transmitter Audio
A-D Dynamic Range: 127dB
Analog distortion .0035 dB
A-D system: NeverClip Zaxcom proprietary (Pat Pending)
Frequency Response: Mode 0: 20 Hz to 16 kHz / T & M Mode 0.2 Hz to 16 kHz
High Pass Filter: Off or 30 to 220Hz, step 10Hz (6 dB per octave)
System Group Delay: 3.6 mS
Mic Connector: 3-Pin or 5-Pin XLR
Analog Mic Power: 48 V Phantom (10 mA max)
Digital Mic Power: 10 V AES42 compatible (200 mA max)
Mic impedance: 4.7 k Ω
ADC Bit-Depth: 24 Bits
ADC Sampling-Rate: 24 Bits
Audio Interfaces: Balanced analog mono, balanced stereo, AES42, AES

Time code Reader/Generator
Clock Accuracy: 1.54PPM (1 Frame Out in 6 Hours)
Timecode Type: SMPTE
Timecode Frame Rates: 23.98, 24, 25, 29.97NDF, 29.97DF, 30NDF, 30DF  .

Media: MicroSD Card (Flash Memory)
File Format: .ZAX
Recording Time: 96 Hours (16 GB card).


2.4 GHz ZaxNet Receiver
RF Frequency Range: 2.403 to 2.475 GHz
RF Modulation: Digital Spread Spectrum
RF Frequency Step: 0.001 GHz (1 MHz)
RF Bandwidth: 1 MHz
Channel Separation: 2 MHz
Sensitivity: -96 dBm


Weight: 7.5 oz without batteries
Dimensions (H x W x D): 5 cm x 11.5 cm x 4 cm
Display: Graphic LCD.


Type: 3 AA cells
Battery Life is dependent on Battery type and microphone power requirements


All Specifications subject to change without notice

Zaxcom Digital Wireless is protected under patent #’s: 7,711,443 & 7,929,902