IR T3 Infrared Transmitter user manual (MAN 295)

Summary

The maker's manual for its two-channel IR T3 infrared transmitter, with coverage by receiver type and its notes on sunlight, plasma screens and what blocks the signal.

Key findings

• Describes a combined modulator and emitter that transmits two channels at once, on 2.3 and 2.8 MHz or on 3.3 and 3.8 MHz, frequencies it says "minimize high-efficiency lighting interference"; no FCC licence or radio approval is needed.
• Gives single-channel coverage of up to 32,000 sq ft (2,972 m²) with its RX22-4 handheld receiver and 19,000 sq ft (1,765 m²) with its RX20 stethoset (under-chin) receiver.
• Says the coverage pattern can be affected by direct or indirect sunlight, reflections from walls and room construction, and that radiation does not drop to zero outside the pattern; most objects block infrared, so the transmitter "cannot be concealed behind walls, glass, curtains, etc."
• Warns that a plasma monitor or television can degrade the audio quality, and that the transmitter should be placed as far from one as possible.
• Calls the transmitter ideal for music, theatre and audio description.

Limits

The maker's figures for its own products, without independent measurement. It does not discuss LED lighting or outdoor use. Date from the PDF's creation date; the manual carries a 2024 copyright.

Read the original

williamsav.com/wp-content/uploads/2024/11/MAN-295-IRT3-User-Manual.pdf

Link checked 9 October 2026. We link to the original and do not host copies.

Cited in

• How many receivers and neckloops does each code require, and how should a loan pool be run?Partly answered
• Where does infrared assistive listening work, and where does it fall short?Partly answered
• Can venue broadcasts be spoofed, hijacked or jammed, and what protects them?Partly answered

Cite this source

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