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Wireless and Wired

UHF In Ear Monitoring System – 900

The 425-900 UHF In Ear Monitoring System sets new standards in terms of unmatched audio clarity, robust RF performance coupled with advanced configuration features to meet the most demanding professional applications.

Key benefits:

  • 20 channel support for maximum coverage and reduced interference.
  • Infra red transmission of settings between base station and beltpack to speed up configuration.
  • Seamless integration with other Trilogy intercom systems for maximum communications reach and improved return on investment.
  • LCD display allows for instant visual confirmation of settings, levels and channel selections.

Complementing its 20 channel capability, the 425-900 base station offers two line inputs, each with independent level control and bar graph indicators, enabling mono or stereo operation. Key focus has been placed on ease of programming with provision for settings to be synchronised between the base station and beltpack wirelessly via the infra red link.

Seamless integration with all Trilogy Intercom systems is effected using standard balanced 4-wire connections together with the comprehensive IFB utility incorporated within the Trilogy configuration software.

The beltpack is intended for use with the Trilogy 420-26-02 flexible eartube, however the standard 3.5mm jack allows simple connection to most popular earpieces.

Key Features – Beltpack:

  • Available in different frequency groups to suit local regulations.
  • Compliant with new UK legislation.
  • Advanced configuration menu with display.
  • IR Sync facility - transfers settings between base station and beltpack.
  • 20 selectable channels.
  • Dual line inputs with level controls and LED input level indicators.
  • Detachable front antenna with provision for adding a remote antenna.

Key Features - Base Station:

  • LCD display displays menu and settings.
  • Dual auto scan mode.
  • Volume limiter.
  • Tri-colour battery status LED.
  • Uses standard AA batteries.





RF Carrier Range

470-952 MHz (region dependent)


FM MPX Stereo. ± 34kHz deviation

RF output power

10/50/100mW (region dependent)

Compatible frequencies

20 per band

Operating range

90m under optimal conditions

Audio frequency response

35 Hz - 15 kHz ±3 dB

Total harmonic distortion

<0.8% typical (1 kHz)

Antenna Connector

50? BNC

Operating temperature

-18oC to + 57oC

Base Station

Audio input





XLR/1/4 inch jack combo



Nominal: +4dBu

Max: +23.3dBu


197 x 166 x 42 (mm)



Base Station

User Controls


Stereo or Mix


EQ Boost

3 position : Off; +2dB; +4dB @10kHz


Volume Limiter

Adjustable 3 - 9

Earpiece Connector

3.5mm jack skt

Earpiece Impedance

9.5? minimum

Battery Type

2 x AA

Battery Life

Typically 5-7 hr


83 x 65 x 22 (mm)



Ordering Information


Base Station P9T - K1 (596-632 MHz - Ch 38-40) With PS41UK

UK Mains Adaptor 230VAC


Base Station P9T - K1E (596-632 MHz - Ch 38-40) With PS41E

EU Mains Adaptor 230VAC


Base Station P9T - R22 (790-830 MHz - Ch 63-65) With PS41UK

UK Mains Adaptor 230VAC


Base Station P9T - R22 (790-830 MHz - Ch 63-65) With PS41E

EU Mains Adaptor 230VAC


Beltpack P9R - K1 (596-632 MHz - Ch 38-40)


Beltpack P9R - R22 (790-830 MHz - Ch 63-65)


External Antenna For Use P9T - K1 Base Station. Includes 8 m cable


External Antenna For Use P9T - R22 Base Station Includes 8 m cable


Presenters Acoustic Tube Earpiece for use with IEM Beltpack

Includes coiled acoustic eartube, clothing clip & cable fitted with 3.5mm jack plug

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