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Overview: The Sennheiser Set 840-S is an RF stereo TV listening
system and is especially suited for those who wear hearing aids with a built-in
induction coil (t-coil). Easily connected to a TV, hi-fi system or radio, the
Set 840-S produces excellent sound, transmitted from the receiver to the hearing
aid via wireless induction using the included induction loop. Alternatively, you
can connect headphones or induction couplers to the lightweight clip-on receiver.
T-Coils: A t-coil (or telecoil) is a very small coil of wire
built within some hearing aids that serve as an antenna. It can be activated by
a switch on the hearing aid when it is set to the "T" position. Hearing
aids with t-coils allow the wearer to have much clearer hearing without feedback.
To create the proper magnetic field, a personal induction loop (such as the one
included with the Set 840-S) or a larger, full room loop is needed. Approximately
30% of hearing aids in the US have t-coils.
RF Wireless Range: The Sennheiser Set 840-S provides a wireless
mobility range of up to 100 feet. It can transmit through walls, so
you don't have to be in the same room as your TV or audio system.
RF wireless receiver: The RF wireless receiver features a
stethoscope design. The receiver is ideal for connection to hearing aids with
a T setting using the included induction loop or headphones (with a 3.5mm jack).
RF Transmitter/Charging Station: The RF transmitter/charging
station connects to your television and then wirelessly transmits a stereo audio
signal to the stethoscope-style wireless receiver. The RF transmitter/charging
station also recharges the integrated battery inside the wireless receiver when
they are placed on the base.
System Connections: The included RF transmitter/charging station
features a 3.5mm input to connect to your television's audio or headphone output
using the supplied stereo minijack cable, minijack-to-RCA cable, or 1/4"
Microphone: The Sennheiser Set 840-S comes supplied with an
external microphone which picks up the television's audio from the TV's built-in
speaker. The microphone plugs into the 3.5mm audio input on the back of the RF
transmitter/charging base and then is placed near the speaker of the television.
Auto Tuning: The wireless receiver automatically searches
for one of the 3 channels (925.95, 926.8, 927.5 MHz) of the transmitter to tune
in your television's audio.
Ergonomic Controls: Ergonomic controls and visual feedback
of certain operations make the Set 840-S easy to use. There is a large, ergonomic
volume control on the stethoscope-style receiver to adjust volume level. There
is also a balance control on the receiver to adjust the balance so that you hear
equally well with both ears.
Three Selectable Hearing Settings: The Sennheiser Set 840-S
offers 3 selectable hearing settings on the transmitter. These settings optimize
speech intelligibility due to switchable compression and treble emphasis.
Auto Power: The RF wireless receiver automatically turns-on
when you place them on your ears and automatically turns-off when you take them
out (after 30 seconds). If you are not within the range of the transmitter, the
receiver automatically switches off after 3 minutes.
Power Supply: The RF wireless receiver features an integrated
lithium-polymer battery to ensure a long operating time of up to 9 hours. The
receiver charges when it is rested on the transmitter/charging station (up to 3
hours). It can be placed in the transmitter's charging compartment facing in
either direction. The transmitter/charging station operates off of standard AC
household current using the supplied AC power adapter.
- Modulation: FM, stereo
- Carrier Frequency: 925.95, 926.8, 927.5 MHz
- Range: up to 100'
- Frequency Response: 50-16,000 Hz
- THD: <1% (1kHz)
- Signal-to-Noise Ratio: 70 dB (A)
- Operating Time: up to 9 hours
- Charging Time: approximately 3 hours