Current Thinking InfraRed Modulator & Radiator

The X750 is a compact combined modulator and radiator for infrared
assistive listening systems, and forms the main transmitter in the Infra~Hear™
range of products.

Using high frequency modulation at 2.3MHz the Infra~Hear™ products are
immune to interference from energy saving lighting and plasma displays.
Due to its compact design the unit can be discreetly placed in classrooms and
meeting rooms, and is the ideal choice for small to medium sized locations, as
well as museums and tours where defined coverage is required.
Area coverage can be increased by using up-to four slave units, increasing
flexibility.

By using an industry standard universal input, the system can be stand-alone
using a microphone (with 12VDC phantom available to allow use of electret
types) or connected to the main sound system using a balanced line connection
for the highest quality sound.
An Automatic Gain Control (AGC) provides the correct modulation signal over a
wide range of audio inputs, ensuring maximum modulation with no overload.

Key Features

• 750mW Power covers up-to 100 square metres
• High frequency modulation, free from lighting interference.
• Simple installation with included bracket
• Uses standard connectors
• Switchable Mic, Line and Mic with Phantom on XLR
• Switchable VOX operation for power saving
• Slave available for larger area coverage

Specification.
The unit shall be a wideband infrared modulator with a nominal deviation of ±50
kHz. The Carrier frequency must be 2.3MHz. The unit must have a 3-pin XLR socket
AF input with a switchable input gain from 60dbV to -4 dBV and a switchable
12VDC Phantom available to power electret type condenser microphones. The unit
shall have an AGC circuit to cover variances in the signal level with a range of 20dB
minimum. The AF frequency response must be 30-18,000 Hz, with THD equalling
<1%. The AF signal-to-noise ratio shall be better than 60 dB(A) rms. The RF output
impedance shall be approx. 75Ω. There shall be 10 diodes. The maximum coverage
area shall be approximately 100 m, with a radiating power of 750mW. The operating
voltage shall be 9V AC or 24VDC supplied via a standard 2.1mm DC Jack. The
current consumption shall be 250 mA. The dimensions shall be approx. 132mm x
132mm x 115mm with the supplied bracket and weigh approx. 700g.