Transmitters · TX-400 Mobi

TX-400 Mobi pocket transmitter: compact, AAA battery powered, with mic input

A transmitter that fits in your pocket: 3.5 mm jack input for music, mic input with its own volume control, powered by 3 AAA batteries.

For guides, instructors and speakers on the move: silent walks, tours, yoga, fitness and small events.

3 / 5Channelsavailable versions

100 mRangeup to

3× AAAPowerAAA batteries

StereoAudioS/N > 75 dB

The transmitter

Small size, voice and music always with you

The TX-400 Mobi fits in your pocket and is ready in seconds. Plug your music source into the 3.5 mm jack and the mic into its dedicated input, pick a channel and transmit in stereo to every headphone in the group.

  • 3.5 mm jack for smartphones, players and external sources.
  • Mic input: 3.5 mm jack with volume control.
  • Multichannel: 3- or 5-channel versions.
  • 3 AAA batteries: no fixed power needed.
  • Stereo audio, S/N > 75 dB, distortion < 1%.
Audio and mic inputs on the TX-400 Mobi transmitter
Video

See the TX-400 in one minute

The video covers the controls, inputs and channel selection. The full transcript is below.

Introduction:
The Silentsystem TX-400 Mobi stands out for being light and compact, delivering high-definition audio and up to 10 hours of battery life, ideal for extended use on the move.

Top controls:
On top of the device you’ll find the power button, along with the 3.5 mm audio inputs for the mic and external music devices, for simple, instant control of your audio sources.

Channel selection:
To select the transmit channel, press and hold the “M” button for a few seconds. Then use the two buttons next to it to change the frequency, and confirm by pressing “M” again.

Charging:
On the right side of the device is the mini-USB port for the charging cable, so the device is always ready to go.

Conclusion:
With its battery life, ease of use and compact design, the Silentsystem TX-400 Mobi is an ideal solution for dynamic events, guided tours and portable wireless audio applications.

Specs

TX-400 Mobi specifications

Spec Value
Model Silentsystem TX-400 Mobi
Type Pocket RF wireless audio transmitter
Technology UHF / RF, FM modulation
Channels 3- or 5-channel versions
Audio input 3.5 mm jack
Mic input 3.5 mm jack, with volume
Audio mode Stereo
Range Up to 100 m (about 330 ft)
Transmit power < 10 mW
Frequencies 863 MHz / 915 MHz
Frequency response 30 – 20,000 Hz
S/N ratio > 75 dB
Distortion < 1%
Power 3 AAA batteries

Actual range depends on the environment, obstacles and radio interference.

Recommended uses

Compatible headphones

Why choose them

Pocket-size, for people on the move

  • Pocket format: take it anywhere, switch it on in a flash.
  • Music + mic: 3.5 mm jack and mic input with its own volume control.
  • AAA batteries: no power cord, no outlet.
  • Up to 100 m (about 330 ft): ideal for groups, rooms and routes.
  • No internet connection: direct RF radio transmission.
Controls on the TX-400 Mobi portable transmitter
FAQ

TX-400 FAQ

Yes: it’s a pocket transmitter, designed for use on the move.

A 3.5 mm jack audio input for your music source and a 3.5 mm jack mic input with volume control.

With 3 AAA batteries, so there’s no need for an outlet.

Up to about 100 meters (about 330 ft). Actual range depends on the environment and obstacles.

No. The TX-400 transmits over radio frequency (RF) and doesn’t require any connection.

With Silentsystem SX-839, SX-809, SX-808, SX-610, SX-707 and SX-553 headphones.
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