Williams Sound MOD 112 Troubleshooting guide

Installation
Guide &
User
Manual
SoundPlus® Two–Channel Infrared System
Large Area Infrared Listening System
Modulator Model WIR MOD 112
Transmitter Model WIR TX6
Receiver Models WIR RX5, RX6
Williams Sound
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MAN 064

SoundPlus® Two–Channel Infrared Listening System
Installation Guide and User Manual
Contents Page
System Overview 4
Installation Procedures
Step 1: TX6 Transmitter Setup 5
Step 2: TX6 Power Wiring 8
Step 3: Baseband Cable Connection 9
Step 4: MOD 112 Modulator Installation 9
Step 5: Testing The System 11
Controls and Features
MOD 112 Front Panel 12
MOD 112 Rear Panel 14
TX6 Transmitter 15
Receiver Instructions 16
Receiver Management 17
Troubleshooting 17
Warranty 18
Specifications 19
Note: Taking a few minutes now to read these instructions will save time and ensure
proper system operation.
NOTICE
Infrared receiver performance can be degraded if this system is used in close proximity to
high-efficiency lighting equipment with solid state ballasts (i.e. high frequency fluorescent).
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Williams Sound
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TX6 Transmitter
MOD 112 Modulator
TFP 016
Power Supply
Baseband In
Baseband Out
Phones
Infrared
Test Out
MOD 112 Two-Channel Infrared System Modulator Williams Sound
Power
CXR
Limit
Compress
Discrete
Stereo
Audio Mode Phones
CH1
CH2
CXR
-21 -18 -15 -12 -9 -6 -3 0 +3 [phone] +3 +6
5
0
1
2346
78
9
10
CH 1 Level CH 2 Level
Channel 1 Channel 2
5
0
1
2346
78
9
10
TFP 010
Power Supply
Power On Indicator
Baseband Present
Indicator
MOD 112 Modulator
TFP 016
Power Supply
Baseband In Baseband In
Baseband Signal
Baseband Out
Phones
Infrared
Test Out
Baseband 112 Two-Channel Infrared System Modulator Williams Sound
Power
CXR
Limit
Compress
Discrete
Stereo
Audio Mode Phones
CH1
CH2
CXR
-21 -18 -15 -12 -9 -6 -3 0 +3 [phone] +3 +6
5
0
1
2346
78
9
10
CH 1 Level CH 2 Level
Channel 1 Channel 2
5
0
1
2346
78
9
10
Williams Sound
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TX6 Transmitter
TFP 010
Power Supply
Williams Sound
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TX6 Transmitter
TFP 010
Power Supply
Power On Indicator
Baseband Present
Indicator
System Overview
The Williams Sound Two–Channel Infrared System,
Model TX600 consists of a MOD 112 Modulator
and one or more TX6 Transmitters (also called emit-
ters) which use invisible infrared (IR) light waves to
broadcast speech or music to wireless infrared
receivers.
The MOD 112 accepts a variety of audio inputs and
sends 95 kHz and 250 kHz frequency modulated
signals to the TX6 Transmitter via a coaxial cable.
The transmitter emits invisible infrared light into the
listening area. Infrared receivers detect the transmis-
sion and convert the light signals back into audio
signals.
The system is designed to transmit high quality
audio for hearing assistance and language translation
applications. Because the system uses infrared light
for transmission, it is not affected by interference
from radio equipment and does not interfere with
radio equipment. No FCC license is required.
A single TX6 Transmitter will cover up to 10,000
square feet of listening area in single channel mode
and 5,000 square feet in two channel mode. Larger
areas can be covered with additional transmitters.
The transmission is confined within opaque walls,
making it especially appropriate for applications in
which security is an issue, such as courtrooms and
corporate boardrooms. The Williams Sound Infrared
System is also commonly used where multiple sys-
tems are needed in adjacent rooms, such as movie
theaters and conference centers, without “spillover”
from adjacent rooms.
The system can be used with a microphone as a
stand-alone system, or it can be connected to an
existing sound system. Infrared Systems cannot be
used in bright sunlight, which contains large
amounts of interfering infrared light.
Fig. 1a: One Modulator / One Transmitter
Fig. 1b: One Modulator / Two Transmitters
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TX6
25°
25°
250 ft.

130 ft.
Two Channel Coverage Single Channel Coverage

Two Channel Coverage
Top Perspective
Single Channel Coverage
Installation Procedures
Installation Step 1: TX6 Transmitter Set-Up
Selecting a Mounting Location
The most important principle to understand when
installing an infrared system is that invisible infrared
light behaves just like visible light. It does not pass
through opaque objects such as walls, curtains, or
people. It does pass through windows and door
openings and can bounce and scatter off reflective
walls, floors, and ceilings. The IR transmitter panels
cannot be concealed or covered up, nor can the
infrared “eye” on receiver units. Receivers work best
with a clear line-of-sight to the transmitter panels.
The TX600 Two–Channel Infrared System should
not be installed outdoors or indoors where there is
considerable direct sunlight. Sunlight generates
infrared interference. Certain types of high-efficien-
cy lighting fixtures can also generate interference
because they use high frequency modulation.
Illumination Patterns
The infrared illumination pattern from a single trans-
mitter is cone-shaped, with a 50° angle. The hori-
zontal and vertical patterns are identical. Figures 2
and 3 show examples of coverage patterns.
These patterns are the direct radiation pattern. The
infrared radiation does not drop to zero outside the
illustrated patterns; it decreases. It still may be use-
able at a greater distance, depending on receiver sen-
sitivity and reflection characteristics of the room.
Figure 2: Infrared Illumination Patterns
Maximizing Coverage By Using Two Transmitters
Note: Single Channel Coverage Area = 10,000 sq. ft.
Two Channel Coverage Area = 5,000 sq. ft.
Figure 3: Side Perspective
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Infrared light reflects off most surfaces and scatters,
which increases the coverage area. Rough surfaces
tend to absorb infrared light, minimizing reflections,
and limiting coverage to the direct illumination pat-
tern.
It’s helpful to think of the IR transmitter as an invisi-
ble floodlight. You want to aim it so listeners are
“flooded” with infrared light.
It’s desirable for the illumination patterns to overlap
when multiple transmitters are used. Placing the
transmitters high above the audience (15–30 ft.) and
aiming them slightly downward (5°–15°) will ensure
the longest “throw” of the infrared beam. Angling
the transmitter inward towards the center of the
room also increases the coverage of the seating area.
Remember that opaque objects block the infrared
light. Thus, transmitters cannot be concealed behind
an opaque walls, curtains, etc. Neither should trans-
mitters be used in areas of extreme high or low tem-
peratures, humidity,or chemical environments.
Coverage Area
The TX6 Transmitter is designed to distribute its
power equally among the channels sent to it for
transmission. Thus, when only a single channel is
present, the TX6 uses all its power to broadcast the
lone signal, achieving a coverage area of approxi-
mately 10,000 square feet. When two signals are
sent to the TX6 (as is the case when the MOD 112 is
in Stereo mode or in Discrete mode when both chan-
nels are in use), the TX6 divides its power equally
among the two signals. This makes for a coverage
area of about 5,000 square feet. This important prin-
ciple is illustrated in Figure 2.
If you’re not getting sufficient coverage with a sin-
gle, properly installed transmitter panel, you’ll need
to add additional TX6 Transmitters to achieve full
coverage of your listening area.
Figures 2 and 3 illustrate infrared light patterns and
recommended transmitter locations. In listening
areas up to 5,000 square feet, the TX6 Transmitter
panel should be installed on the front wall of the lis-
tening area in a position to flood the listening area.
It must be above the audience to permit a direct line
of sight between the transmitter and people wearing
receivers when the people are standing or sitting.
Listening areas of more than 5,000 square feet will
require two or more TX6 Transmitters for complete
coverage. Place one transmitter panel on the left side
of the front wall and the other on the right hand side.
The two transmitters will be connected with an
RG-58 cable. For extremely large venues, additional
TX6s should be located to maximize coverage
throughout the listening area.
Installation Step 2: TX6 Power Wiring
For U.S. Applications:
The TX6 Transmitter is supplied with a low-voltage
wall transformer power supply (TFP 010). Two-con-
ductor 18 ga. zipcord is included with the transmit-
ter.
For Applications Outside The U.S. Requiring
240 VAC Mains Supply:
See page 18.
WARNING! Shorting the power supply output
terminals will blow a non-replaceable internal
fuse, destroying power supply unit!
DO NOT CONNECT THE POWER SUPPLY TO
AC POWER YET!!!
Step 1: Determine the length of zipcord needed to
reach from the transmitter to the AC wall
outlet where the power supply will be
plugged in. Zipcord length must not
exceed 200 feet.
One end of the zipcord has a 3-pin Molex
connector, the other end is bare. Cut the
bare end of the zipcord to length. Strip
this end down the middle approximately
1inch, then strip both of the resulting
strands about 1/8 inch. Install the crimp-
on spade terminals supplied and connect
these to the screw terminals on the
TFP 010 Power Supply. Polarity is not
important since AC power is being used.
Step 2: Plug the 3-pin connector into the TX6’s
Power In connector.
Step 4: Plug in the TFP 010 Power Supply
The Power Indicator LED in the top cen-
ter of the front panel glows when the TX6
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Figure 4: Mounting The TX6
The TX600 Two–Channel Infrared System
includes a kit for mounting the TX6 to a wall or
ceiling.
1. Use the 5/32" allen wrench to loosen the ten-
sion bolt in the clamp assembly enough to
release the ball. DO NOT unscrew the ten-
sion bolt completely. Using the mounting
plate as a template, mark the hole locations
on the mounting surface. Use fasteners
appropriate for the mounting surface (wood
screws, lag bolt, wall anchor) to attach the
mounting plate. Recommended fastener size
is 1/4".
2. Attach the clamp plate to the rear of the
transmitter, using (2) 1/4 x 20 x 1/2" socket
head screws and 3/16 hex wrench provided.
Place the mounting plate in the position indi-
cated for ceiling or wall mounting.
3. Place the transmitter/clamp plate assembly
onto the the mounting plate ballshaft. Aim
the transmitter at the desired downward
angle and support it fully while using the
hex wrench to tighten the tension screw.
After initial installation, the ball will slowly
compress under pressure. Check the tension
screw after 15 minutes and re-tighten if nec-
essary. DO NOT over-tighten.
If rotational adjustment is required, used a
7/16" open-end wrench to loosen the jam nut
on the ballshaft. Rotate the transmitter and
re-tighten the jam nut.
Fig. 4a: SB-3 Wall/Ceiling Mount
Mounting Plate Ballshaft
Clamp Plate
To Wall
Or To
Ceiling Transmitter
Jaw
Tension Screw
Fig. 4b: Bracket 012 Ceiling Mounting
Fig. 4c: Bracket 012 Wall Mounting
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TX6 Transmitter
MOD 112 Modulator
TFP 016
Power Supply
TFP 010
Power Supply
Williams Sound
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Model WIR MOD112 Two-Channel Infrared System Modulator
Baseband Out
TX6 Transmitter
TFP 010
Power Supply
Baseband In
Baseband Out
To Additional 
TX6 Transmitters
Baseband In
Baseband Out
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Figure 5: TX6 Transmitter Wiring Detail
is on. The Baseband Indicator LED is
located in the bottom center of the TX6
front panel and glows when a baseband
signal is present.
Note: The TX6 transmits when a baseband sig-
nal is present. The TX6 shuts off when no
baseband signal is present. This auto shut-
off feature preserves the life of the IR
LED’s and reduces power consumption
when the transmitter is not in use.
This system is designed for Class 2, low-
voltage wiring. Always follow local elec-
trical codes when doing low voltage
wiring.
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Installation Step 3:
Baseband Cable Connection
If You’re Using One Transmitter:
Step 1: Determine the length of RG-58 coaxial
cable needed to reach from the transmitter
to the modulator unit. The modulator is
usually located with the other sound
equipment to simplify audio connections.
100 feet of coaxial cable is included with
each transmitter. You will need to cut it to
length. Additional RG-58 coax can be
added. Make sure you leave some slack at
each end.
Step 2: Install BNC connectors on each end of the
cable. (See Figure 6.)
Step 3: Connect the Baseband cable to the
Baseband Out jack on the MOD 112 mod-
ulator and to the Baseband In jack on the
TX6 transmitter. (See Figures 5 and 7.)
If You’re Using More Than One Transmitter:
Step 1: Determine the length of coaxial cable
needed to reach between the transmitters.
100 feet of coaxial cable is included with
each transmitter. You will need to cut it to
length. Additional RG–58 coax can be
added. Make sure you leave some slack at
each end.
Step 2: Install BNC connectors on each end of the
cable. (See Figure 6.)
Step 3: Connect the baseband cable from the
Baseband Out Jack on the first transmitter
in the chain (the one connected to the
MOD 112 Modulator) to the Baseband In
jack on the next TX6 transmitter in the
chain. Use the cable clamps and screws
provided to secure the cable. The coax can
also be routed through conduit before
attaching BNC connectors. You can chain
as many transmitters together as you need.
Remember that each transmitter needs its
own power supply.
Installation Step 4: MOD 112 Modulator
Location
The Modulator is usually located with the sound
system amplifier or mixer for easy access to an
audio input signal. For portable systems, the modu-
lator can be placed near the transmitter or wherever
is most convenient.
Power Connection For U.S. Applications:
Step 1: Connect the power supply to the 3-pin
Molex connector located on the rear of the
MOD 112. (See Figure 7.)
Step 2: Plug the power supply into an AC outlet.
Power Connection For Applications Outside The
U.S. Requiring 240 VAC Mains Supply:
See page 18.
Baseband Cable Connection
The MOD 112 drives one transmitter. The TX6
repeats the baseband signal, so any number of trans-
mitters can be used. The modulator outputs CAN-
NOT be split with CATV splitters.
Audio Connection
The MOD 112 accepts audio signals from industry
standard low impedance microphones, balanced,and
unbalanced lines.
Microphones
An industry standard 3-pin male connector is used.
Pin 1 is the shield and pins 2 and 3 are audio. Power
for condenser microphones is supplied according to
DIN 45596.
Balanced Lines
A 1/4 inch Tip-Ring-Sleeve (3 conductor) phone
plug is used. The three-pin connectors are used for
mic inputs only.
Unbalanced Lines
A 1/4 inch Tip-Sleeve (2 conductor) phone plug is
used.
8Ohm speaker lines can be connected to the bal-
anced line inputs. Usually it is advantageous to not
connect to the sleeve of the plug, thus avoiding cre-
ating a ground loop.
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Nut Secured Into
Plug Assembly
50 ΩBNC Plug Connector
Plug 
Assembly
Contact
Clamp
Gasket
Washer
Nut
Gasket
Washer
Nut
Cable Jacket
7.92 mm (±.25)
.312 in. (±.01)
Clamp positioned 
against Cable Jacket
Clamp Braid folded
over Clamp and trimmed
Clamp Collar

3.96 mm (±.25)
.156 in. (±.01)
Dielectric
Dielectric
Contact soldered to conductor
and bottomed on dielectric
Plug Assembly
Gasket (Ref.)
Contact Assembly 
inserted into Plug 
Assembly
Figure 6: BNC Connector Assembly 6b
6c
Assembly Procedure
The BNC Connector consists of a plug assembly,
a contact, a clamp, a gasket, a washer, and a nut.
1. Slide nut, washer and gasket over cable end;
then strip outer cable jacket using the recom-
mended strip-length dimension in fig. 6b.
2. Slide clamp over cable braid and position it
against the cable jacket. After clamp is prop-
erly positioned, comb out the braid.
3. Fold cable braid over the clamp and trim it so
that it is positioned against the clamp collar.
See figures 6c and 6d.
4. Using the dimension in figure 6e, strip dielec-
tric to expose the center conductor. If applica-
ble, tin the center conductor.
5. Solder contact to the conductor (using stan-
dard soldering techniques), making sure con-
tact is bottomed on cable dielectric. See fig-
ure 6f.
DO NOT allow a hot soldering iron to touch
cable dielectric. Certain cable dielectric mate-
rials, such as polypropylene, will expand if
they come in contact with a hot soldering
iron.
6. Insert contact into plug assemble until contact
snaps into place. See figure 6g.
7. Thread nut into plug assembly until it is
secured. Recommended cable clamp tighten-
ing torque is 2.8–3.4 N•m [25–30 in.-lb.],
using a 7/16" wrench. See figure 6h.
6d
6e
6f
6g
6h
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25 V, 70 V, and 100 V speaker lines can be connect-
ed to the balanced line inputs using an appropriate
attenuator. “T” pads made with resistors yield better
fidelity than speaker matching transformers.
The MOD 112 transmits audio with excellent fideli-
ty. Therefore, be sure to connect its inputs to signal
sources that supply audio that is the best your sys-
tem can offer. The signal should not be processed by
an equalizer used for an accompanying PA system.
The MOD 112 has excellent signal processing, so
the use of additional limiters or compressors is not
recommended.
Installation Step 5: Testing the System
Step 1: After the baseband cable, power cables,
and audio source are connected, turn the
MOD 112 power switch on. The green
power LED on the front of the MOD 112
should light.
Step 2: Make sure the sound system is on and
your audio source is active. Check the
quality of your audio source signal by lis-
tening through the Phones jack on the
MOD 112’s front. The MOD 112’s
10-segment bar graph level indicator
shows audio level in 3 dB steps at input of
audio level processing circuit.
Step 3: Look at the transmitter panel(s). With the
modulation signal and power connected,
two red lights should be visible on the the
panel–the power indicator at the center top
and the baseband indicator located at the
center bottom.
Step 4: Hold a receiver near the “Infrared Test
Out” LED on the front of the MOD 112.
Turn the receiver on and adjust the vol-
ume. You should be able to hear the audio
signal through the receiver. If not, make
sure the CXR On Indicator is lit and there
is activity on the Level Indicators. If the
lights are not flashing, check your audio
source or the setting of the input level
switch and input level control. If the audio
lights are flashing, but you don’t hear any-
thing from the receiver, try a different
receiver to be sure the receiver is working.
Step 5: Take a receiver into the listening area and
walk around to check the reception. Make
sure the “eye” on the receiver is not cov-
ered up when in use. The receiver will not
work if it is placed in a pocket or purse
and its eye must be able to “see” the trans-
mitter panel. It may be necessary to adjust
the angle of the transmitter(s) to obtain the
best coverage. If coverage is not adequate,
additional transmitter panels must be used.
Model WIR MOD112 Two-Channel Infrared System Modulator
Accessory
Power: 24 VAC, 
50-60 Hz, 10VA
Williams Sound Corp., Minneapolis, MN USA
Balanced 
Mic (XLR)
Bal or Unbal 
Line (1/4")
Ch 1 Audio Input Ch 2 Audio Input
Baseband 
Output
Baseband 
Input
50 Ohms 50 Ohms
Baseband Output Connection
Connect to TX6 here using 
RG-58 cable and BNC connector.
Power Connection
Plug in TFP 016 
Power Supply
Figure 7: Modulator Wiring Detail
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Phones
Infrared
Test Out
MOD 112 Two-Channel Infrared System Modulator Williams Sound
Power
CXR
Limit
Compress
Discrete
Stereo
Audio Mode Phones
CH1
CH2
CXR
-21 -18 -15 -12 -9 -6 -3 0 +3 [phone] +3 +6
5
0
1
2346
78
9
10
CH 1 Level CH 2 Level
Channel 1 Channel 2
5
0
1
2346
78
9
10
Channel 1 and 2 each have individual Level
Controls and Features Controls, Level Indicators and Carrier On Indicators.
They function independently and identically for each
MOD 112 Front Panel channel.
Power Switch
Turns the entire system on and off. The associated
wall mounted power supply stays on at all times and
may operate continuously. There is no “wear out”
mechanism.
Power On Indicator
Indicates actual operation of modulator.Does not
indicate status of power supply.
Level Control
Controls level of audio signal for the associated
channel. Control is connected between the input
amplifier and the audio level processing circuit.
Level Indicator
Bar graph level indicator shows audio level in
3dB steps at input of audio level processing circuit.
Indicator is peak responding and is calibrated so that
optimum level is reached when the amber +3 light
usually blinks and the red +6 light only blinks occa-
sionally.
CXR On Indicator
The Carrier On indicator shows when the associated
carrier is on. Carriers come on when power is
applied, but go off automatically if there is no audio
for approximately 30 minutes. Audio sufficient to
light the –21 level indicator light will reset the timer,
Figure 8: MOD 112 Front Panel
Power Switch
Turns the entire system on and off.
The associated wall mounted power
supply stays on at all times.
Level Control (Ch 1)
Controls level of audio signal
for channel 1.
Level Control (Ch 2) CXR On Indicator (Ch 2)
Controls level of audio signal The Carrier On indicator shows when
for channel 2. the channel 2 carrier is on.
Level Indicator (Ch 2) Mode Switch
Bar graph level indicator shows Selects how the channels are used.
audio level in 3 dB steps at input Separate processing for each channel is
of audio level processing circuit. provided in the Discrete mode, coupled
processing is provided for Stereo Mode.
Power On Indicator CXR On Indicator (Ch 1) Phones Jack & Switch
Indicates actual operation of The Carrier On indicator shows The phones jack monitors the
unit. Does not indicate status of when the channel 1 carrier is on. audio in one, the other or both
power supply. channels, depending on the set-
ting of the Mode and Phones
switches.
Level Indicator (Ch 1) Audio Processor Switch IR LED
Bar graph level indicator shows audio Selects one of the two modes Infrared receivers can be
level in 3 dB steps at input of audio available: Limit and Compress tested using the IR LED.
level processing circuit.
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allowing another 30 minutes before the carrier can
again go off.
After the carrier has automatically gone off, audio
sufficient to light the -21 level indicator light will
turn the carrier back on immediately.
Audio Processor Switch
Selects one of the two modes available.
Limit Mode
The audio processor has little effect on low level
sound. As the level increases, reaching the level to
light the red +6 light on the level indicator, no fur-
ther increase in transmitted level is permitted. This
is necessary to prevent distortion in receivers and
prevent interference with other channels. Limit pro-
duces a very natural sound, and is most desirable for
music. High quality speech is very pleasant to listen
to. However, Limit is not as helpful for hearing
impaired individuals as Compress mode.
Compress Mode
At high levels, 0 to +6, Compress is very similar to
Limit. But at low levels Compress increases the
volume substantially. Hearing impaired people need
an increase in low level to be able to hear most
speech.
Compress is most useful for hearing impaired indi-
viduals and where the input signal is poorly con-
trolled or has great dynamic range.
Mode Switch
The Mode Switch selects how the channels are used.
Separate processing for each channel is provided in
Discrete mode, where the two channels have unrelat-
ed program material such as two different languages.
Coupled processing is provided for Stereo mode,
where the program material is related.
Discrete Mode
The channels operate fully independently. Carrier
timers operate separately,allowing one channel to
go off without affecting the other. The Phones jack
receives one or the other channel, as selected by the
Phones switch. Both channels of the Phones jack
have the same signal.
Stereo Mode
Audio processing is coupled, providing a consistent
stereo image, important when listening with head-
phones. Carrier timers are coupled, requiring both
to have reached approximately 30 minutes before
either carrier can go off. Both carriers go off and on
together. The Phones jack receives stereo sound,
one channel in the left side and the other channel in
the right side. The Phones switch is deactivated.
Phones
The phones jack monitors the audio in one, the other
or both channels, depending on the setting of the
Mode and Phones switches. It is designed to accom-
modate standard professional headphones with a
1/4 inch Tip-Ring-Sleeve (Stereo) plug. Channel 1 is
on the Tip, channel 2 is on the ring and the sleeve is
common. It can also accept any other type of head-
phone or earphone. Monophonic headphones are
acceptable, however will not provide stereo repro-
duction. Headphones with 3.5 mm plugs can be
used with a 1/4 inch to 3.5 mm adapter. If 3.5 mm
stereo phones are used, a stereo adapter is required.
IR LED
Infrared receivers can be tested using the IR LED.
It is of short range only, useful only to about
1 meter. Infrared emitted from this LED is modulat-
ed by the carriers generated in this unit only. If this
modulator is connected to other modulators for addi-
tional channels, their carriers are not emitted by the
LED, and must be monitored at those modulators.
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Model WIR MOD112 Two-Channel Infrared System Modulator
Accessory
Power: 24 VAC, 
50-60 Hz, 10VA
Williams Sound Corp., Minneapolis, MN USA
Balanced 
Mic (XLR)
Bal or Unbal 
Line (1/4")
Ch 1 Audio Input Ch 2 Audio Input
Baseband 
Output
Baseband 
Input
50 Ohms 50 Ohms
Figure 9: MOD 112 Modulator Rear Panel
Input 1 and Input 2
These main inputs to the modulator accept any low Power In 21 VAC to 26 VAC only, 50 or 60 Hz.
(TFP 016 Power Supply)impedance microphone or line level signal.
Baseband Output
Carriers tones of 95 kHz and 250 kHz are provided at this
BNC connector. One 50 ½ device may be connected here using
RG-58 cable. Additional devices may also be connected in series.
Current consumption is approximately 130 mA.
Accessory Connector Baseband Input
Outputs are available directly from several points An additional modulator may be connected here to
in the internal circuitry of the modulator. allow combining carriers for more channels.
The input impedance is 50 ½.
MOD 112 Rear Panel
Input 1 and Input 2
The two main inputs to the modulator accept any
low impedance microphone or line level signal. The
input circuit is constructed with a “studio grade” dif-
ferential amplifier, providing better performance
than that which is available with a transformer while
still being fully protected from RFI/EMI.
Microphone
Any dynamic, ribbon or condenser microphone
equipped with a balanced output and a 3 pin XLR
connector can be used. Power is supplied for con-
denser microphones according to DIN 45596. It
need not be turned off for dynamic or ribbon mics.
Microphones with two conductor 1/4 inch plugs are
not usable.
The minimum acceptable level is approximately 100
µV, and the maximum level before clipping is
approximately 90 mV.
Line
Both balanced and unbalanced line level signals can
be accommodated. The minimum acceptable level is
approximately 100 mV,and the maximum level
before clipping is approximately 10 V.
25 V, 70 V, and 100 V speaker distribution lines can
be connected to the Line input using attenuators
made with resistors or with speaker matching trans-
formers. Resistor attenuators yield better results. The
minimum acceptable level is approximately 100 mV,
and the maximum level before clipping is approxi-
mately 10 V.
Accessory Connector
Outputs are available directly from several points in
the internal circuitry of the modulator. They are
from the output of the differential amplifiers for the
main inputs and from the output of the audio pro-
cessing circuits. The outputs are isolated from inter-
nal circuits and may be used as the installer requires.
Williams Sound
®
Helping People Hear

14

Baseband In
Baseband Out
50 Ohms
50 Ohms
Power In
24VAC
50-60Hz
30W
Omnimount
25-STXMP
Made in U.S.A.Williams Sound Corp., Minneapolis, Minnesota, USA
Power Supply Wiring:
Use NEC, Class 2 Wiring,
18 ga. Min
200 ft. Max. Length (18 ga.)
Baseband Signal Wiring:
Use RG58 Coax,
1000 ft. Max. Length
Note: It is normal for this unit
to feel warm while it is in
operation.
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
WARNING: TO REDUCE THE RISK OF FIRE OR
ELECTRIC SHOCK DO NOT EXPOSE THIS
EQUIPMENT TO RAIN OR MOISTURE.
Multi-Channel
Infrared Transmitter
Model WIR TX6
Williams Sound
®
Helping People Hear
Baseband Output
Carrier tones of 95 kHz and 250 kHz are provided at
this BNC connector. One 50 ½ device may be con-
nected here using RG-58 cable. Additional devices
may be connected by “looping through” the connect-
ed device or by means of a suitable distribution
amplifier. The output impedance is 50 ½.
Frequency accuracy is approximately ± .005%.
Deviation is ± 50 kHz, maximum. Average devia-
tion is dependent on program material and whether
Limit mode or Compress mode is selected.
Baseband Input
An additional modulator may be connected here to
allow combining carriers for channels in addition to
95 kHz and 250 kHz. The input impedance is 50 ½.
Power In
21 VAC to 26 VAC only, 50 or 60 Hz. (TFP 016
Power Supply) Current consumption is approximate-
ly 300 mA.
TX6 Transmitter
Power Input
Three-pin connector for TFP 010 power supply.
Power Indicator LED (front panel)
Located on the front panel in the top center of the
LED window. Red indicator light glows when power
is on.
Note: The TX6 shuts off when no baseband signal
is present.
Baseband Indicator LED (front panel)
Located on the front panel in the bottom center of
the LED window.Red indicator light glows when
baseband signal is present.
Baseband In:
Connects to the Baseband Out jack of the MOD 112
modulator or another TX6 transmitter.
Baseband Out:
Connects to the Baseband In jack of of the next TX6
transmitter in the chain when multiple transmitters
Figure 10: TX6 Transmitter Rear Panel
Baseband In Baseband Out
BNC Connector, 50 ½, BNC Connector, 50 ½,
50 kHz–1 MHz Baseband 50 kHz–1 MHz Baseband
are used.
SB-3 Wall/Ceiling Mount
Template:
An omnidirectional mounting
bracket is included with the
Transmitter. An optional tripod
stand kit is also available (WSC
Part #SS-2).
SB-3 Wall/Ceiling Mount Template Power In
Set of threaded holes for use with omnidirection- Three-pin Molex connector
al mount. for TFP 010 power supply
Williams Sound
®
Helping People Hear

15

Receiver Instructions
Two Channel IR Receiver Model WIR RX5
Make sure the “eye” on the front of the receiver is
not covered up when in use. The receiver is intend-
ed to be worn on the front of the body, hanging from
the lanyard attached to the receiver. The receiver
will not work if it is placed in a pocket or purse. A
variety of earphones, headphones, or a neckloop
telecoil coupler can be used with the RX5 Receiver.
Step 1: To install the batteries, open the battery
compartment using a coin in the slot in the
bottom of the receiver. Press two AA bat-
teries into place, observing proper battery
polarity.
Step 2: Plug the earphone or headphone into the
earphone jack.
Step 3: Turn the receiver on by rotating the vol-
ume control knob clockwise.
Step 4: Choose the appropriate channel using the
push-button channel selector.
Step 5: Adjust the tone to your preference using
the slide switch tone control. To avoid
draining the battery,make sure the receiv-
er is turned offwhen not in use.
Stereo IR Receiver Model WIR RX6
Make sure the“eye” on the front of the receiver is
not covered up when in use. The receiver is intend-
ed to be worn on the front of the body, hanging from
the lanyard attached to the receiver. The receiver
will not work if it is placed in a pocket or purse.
A variety of stereo earphones and headphones can
be used with the RX6 Receiver.
Step 1: Toinstall the batteries, open the battery
compartment using a coin in the slot in the
bottom of the receiver. Press two AA bat-
teries into place, observing proper battery
polarity.
Step 2: Plug the earphone or headphone into the
earphone jack.
Step 3: Turn the receiver on by rotating the vol-
ume control knob clockwise.
Step 4: Adjust the tone to your preference using
the slide switch tone control. To avoid
draining the battery, make sure the receiv-
er is turned off when not in use.
Battery Information for Receivers
For RX5 and RX6 Receivers in normal use, a AA
alkaline battery (BAT 001) will last about 30 hours.
Rechargeable AA batteries will last about 15 hours
per charge.
In the case of rechargeable batteries, most commer-
cially available external charger kits will work well.
If the sound becomes weak or distorted, replace the
batteries. The indicator light may still be on, even
with weak batteries. Do not leave dead batteries in
the receivers, they may leak and damage the receiv-
er.
DO NOT attempt to recharge disposable batter-
ies!
AVOID shorting plus and minus battery termi-
nals together with metal objects. Battery damage
and burns can result.
DO NOT mix rechargeable batteries and charg-
ers from different manufacturers.
Williams Sound
®
Helping People Hear

16

Receiver Management
Different types of facilities will use different
approaches for receiver management and earphone
sanitation. Following are some alternatives that
other customers have used successfully:
1. Regular users purchase their own receiver and
take care of their own batteries and earphone.
2. Some facilities label the receiver and earphone
with the names of regular users so each person
uses the same receiver and earphone.
3. Ushers issue receivers to people who request
them. Earphones are sanitized after use. Foam
ear cushions can be replaced or washed with a
mild detergent, rinsed thoroughly and air-
dried. The EAR 022 Surround Earphone can
be sanitized with an alcohol pad.
4. The receivers are stored in a multiple compart-
ment storage case with a credit card or driver's
license left as collateral for the receiver.
5. Regular users purchase their own earphone or
headphone and bring them to use with
receivers at the facility.
Troubleshooting
Neither TX6 indicator light is on (Fig 1a).
1. Make sure the wall transformer is plugged into
the transmitter and the power switch or any
remote power switch is on.
2. Make sure the electrical outlet is on.
3. Make sure the 24 VAC power supplies are
working.
Only one TX6 light (top) comes on (Fig 1a).
1. Make sure the MOD 112 is on.
2. Make sure the baseband cable is connected
properly.
3. Check to see if that at least one carrier light on
the MOD 112 is on.
No sound through receivers.
1. If some of the receivers work but others don’t,
check for bad batteries or earphones on the
receivers that aren’t working.
2. If none of the receivers work, check to see if
the power and baseband cable are connected
to the transmitter and that the Power and
Baseband Present Indicator lights are ON.
3. Check to see if the modulator is connected
properly to the sound system. The CXR On
Indicator should be lit and there should be
activity on the MOD 112’s Level Indicators.
4. Make sure the “eye” is not covered up on the
receiver. There must be clear line of sight
between the receiver eye and the transmitter
panel.
Sound through the receivers is weak and noisy.
1. Hold a receiver in front of the Infrared Test
LED on the front of the MOD 112 modulator
and listen to the signal. If the signal is weak
and noisy here, check the Input Level switch
and Input Level Control settings. Increase the
input signal level from the sound system by
turning up a mixer control. If the signal
sounds okay,you may need to re-position the
transmitter panels or add additional panels.
Buzzing or humming noise in sound system.
1. Check for ground loops or noise on the input
signal. Call your Authorized Dealer or
Williams Sound for help.
Williams Sound
®
Helping People Hear

17

Warranty
Williams Sound Transmitters and Receivers are war-
ranted against defects in workmanship and materials
for FIVE YEARS. Microphones, earphones, cables,
carry cases, rechargeable batteries and chargers are
warranted against defects in workmanship and mate-
rials for 90 DAYS. This warranty does not extend to
intentional or accidental physical damage. This war-
ranty applies only to products returned to Williams
Sound for service. To return a product for service,
call the phone number below and request a Return
Authorization (RA) number.
Williams Sound Corp.
10399 West 70th Street
Eden Prairie, MN 55344-3459 USA
Phone: [phone]
612-943-2252
Fax: [phone]
Power Connections For Applications Outside
The U.S. Requiring 240 VAC Mains Supply:
MOD 112
Use an appropriate power adaptor supplied by
the local distributor which meets the following
Secondary Specifications:
24 VAC, 10 VA, 50/60 Hz
WIR TX6
Use an appropriate power adaptor supplied by
the local distributor which meets the following
Secondary Specifications:
24 VAC, 30 VA, 50/60 Hz
Williams Sound
®
Helping People Hear

18

SoundPlus™ Multi–Channel Infrared System Specifications
Two–Channel Infrared Modulator, Model MOD 112
Dimensions, Weight: 8.45" (21.5 cm) W x 8.18" (20.8 cm) D x 1.72" (4.4 cm) H, 3 lbs. (1.5 kg)
Color: Black epoxy paint with white legends
Rack Mount: One IEC rack space high, one or two units can be mounted in a single rack space with
optional RPK 005 (single) or RPK 006 (double) Rack Mount Kits
Power: External power supply, 24VAC, 50 or 60Hz, 10 VA maximum
Baseband Output: 50 ½ source impedance
Carriers: 100 mV per carrier
Channel 1: 95 kHz ± 50 kHz deviation, 50 µsec pre-emphasis
Channel 2: 250 kHz ± 50 kHz deviation, 50 µsec pre-emphasis
AGC: Variable slope compressor or soft limiter, switch selected
Carrier Timers: One 30 minute (approx.) timer per channel. Turns off carrier if channel is silent (lowest
light on bar graph does not light) for full 30 minutes.
Operating Req.: 0-50°C ambient temperature, non-condensing, non-corrosive atmosphere
Front Panel:
Power Switch: Two-position rocker, ON/OFF
Power Indicator: Green LED
Audio Level Controls: 1 control per channel
Audio Indicators: One (1) 10 LED bar graph per channel
Carrier LEDs: 1 carrier on indicator LED per channel, green
Limit/Compress Switch: Selects variable slope compression or soft limiting
Stereo/Discrete Switch: Selects stereo (coupled processing and timers, stereo monitoring)
or discrete (Independent processing and timers, mono monitoring)
Phones Switch: Selects CH 1 or CH 2 for phones when mode is in discrete position
Phones Output: 1/4" stereo phones jack. Produces stereo or mono output depending on mode selected.
Accepts stereo or mono phones. Any impedance
Infrared Test LED: IR LED for receiver testing, monitoring, and audio signal testing.
Effective to about 2 feet from front panel
Rear Panel:
Balanced (Floating) Line Input: 1/4" TRS jack. Accepts unbalanced or balanced line level inputs
Mic Input: lo-Z, 100 µV min. to 90 mV max. 1 mV nominal, 3 k½ input impedance
Supplies simplex power 20 V (DIN45296) for condenser mics
Baseband Output: (1) BNC connector, 50 ½, 100 mV RMS per carrier, use RG-58 cable
Baseband Loopthru Input: (1) BNC connector, 50 ½
Power Connections: 3-pin molex
Emitter Type: For use with Williams Sound Linear Emitters. For multi-emitter systems, each emitter
repeats the baseband signal to drive the next emitter in the chain.
Accessory Connector: 9-pin, Sub–D female, various circuit connections
(See diagram on top panel for details)
Note: Infrared receiver performance can be degraded if this system is used in close proximity
to high-efficiency lighting equipment with solid state ballasts (i.e. high frequency fluores-
cent).
Williams Sound
®
Helping People Hear

19

Infrared Emitter, Model TX6
Dimensions, Weight: 11.125" (28.3 cm) W x 8.125" (20.6 cm) H x 3.25" (8.3 cm) D, 3.25 lbs. (1.6 kg)
Color: Black epoxy paint with white legends, red acrylic window
Wall Mount: Omnidirectional mount included for wall and ceiling mounting.
Tripod Mount: Optional SS-2 Tripod Stand Kit available
Power: External power supply, 24 VAC, 50 or 60 Hz, 50 VA, 0.9 A nom. current drain
Transmitter shuts off when baseband signal is not present
Operating Req.: 0-50° C ambient temperature, non-condensing, non-corrosive atmosphere
Coverage Area: Single-channel mode: 10,000 sq. ft. (930 sq. m); Two-channel mode: 5,000 sq. ft. (465 sq.
m)
50° cone pattern, see coverage diagram
Front Panel:
Power Indicator: Red LED, visible in lower front of window
Baseband Indicator: Red LED, visible in upper part of window
Rear Panel:
Mounting Holes: One set of threaded holes for use with omnidirectional mount (included)
Two threaded holes on sides of the cabinet for Tripod Stand Kit
Baseband Input: BNC connector, 50 ½, 50 kHz to 1 MHz carriers, 100 mV nominal per carrier,
10 V RMS maximum aggregate baseband amplitude
Baseband Output: BNC connector, 50 ½, 50 kHz to 1 MHz baseband
Power Connection: 3-pin molex
Baseband Cable: RG-58 Coax, BNC-connectors
Power Cable: NEC Class 2 wiring, 2-conductor, 18 ga.; 200 foot (61 m) max. length (for 18 ga. wire)
Wire Gauge Options: 22 ga.: 0–10'; 20 ga.: 0–75'; 18 ga.: 0–200'
Each TX6 Transmitter requires its own 24 VAC Power Supply
Two–Channel Infrared Receiver, Model WIR RX5
Size and Weight: 3-5/8" L x 2-3/8" W x 7/8" H (9.2 cm x 6 cm x 2.2 cm)
Color and Material: Gray, shatter-proof polypropylene
Battery Type: 1.5 V (AA) x 2, Alkaline (BAT 001) or Rechargeable AA Ni-Cad (BAT 026)
Battery Life: 30 hours with BAT 001, 15 hours/charge with BAT 026, 25 mA, nom. current drain
Modulation Frequencies: 95 kHz FM, 50 µS de-emphasis OR 250 kHz FM, 50 µS de-emphasis
Signal to Noise Ratio: 60 dB with WIR TX6
Controls: Combination volume/On-Off knob, Push–button channel selector, Slide switch tone con-
trol
Audio Output: 3.5 mm mono mini phone jack, maximum into 16 ½
Acoustic Output: 130 dB MAX SSPL90 with EAR 013
The RX5 Two-Channel Infrared Receiver can be used with a Neckloop TeleCoil Coupler
(NKL 001) to magnetically couple into a hearing aid that has a telephone pick-up coil.
Stereo Infrared Receiver, Model WIR RX6
Size and Weight: 3-5/8" L x 2-3/8" W x 7/8" H (9.2 cm x 6 cm x 2.2 cm)
Color and Material: Gray, shatter-proof polypropylene
Battery Type: 1.5V (AA) x 2, Alkaline (BAT 001) or Rechargeable AA Ni-Cad (BAT 026)
Battery Life: 30 hours with BAT 001, 15 hours/charge with BAT 026, 25 mA, nom. current drain
Modulation Frequencies: 95 kHz FM, 50 µS de-emphasis AND 250 kHz FM, 50 µS de-emphasis
Signal to Noise Ratio: 60 dB with WIR TX6
Controls: Combination volume/On-Off knob, Slide switch tone control
Audio Output: 3.5 mm stereo mini phone jack, maximum into 16 ½
Williams Sound Corp.
10321 West 70th St., Eden Prairie, MN 55344-3446
U.S.A. 800-843-3544 / 952-943-2252 / FAX: [phone]
© 1996, Williams Sound Corp. MAN 064B