Illustrations in this publication are approximate representations of the actual
equipment, and may not be exactly as the equipment appears.
HM Electronics, Inc. is not responsible for equipment malfunctions due to
erroneous translation of its publications from their original English version.
The HME logo and product names are registered trademarks of HM Electronics. All rights reserved.
This device complies with Part 15 of the FCC rules. Operation is subject to the following two conditions:
MANDATORY SAFETY INSTRUCTIONS
IC Notice to Users English/French in accordance with RSS GEN Issue 3
(1) This device may not cause harmful interference, and (2) This device must accept any interference received, including interference
that may cause undesired operation.
NOTE: This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the
FCC rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated
in a commercial environment. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in
accordance with the instruction manual, may cause harmful interference to radio communication. Operation of this equipment in a
residential area is likely to cause harmful interference, in which case the user will be required to correct the interference at his own
expense.
Changes or modifications not expressly approved by HM Electronics, Inc. could void the user’s authority to operate this equipment.
FOR INSTALLERS AND USERS
Use only manufacturer or dealer supplied antennas.
The Federal Communications Commission has adopted a safety standard for human exposure to RF (Radio Frequency) energy,
which is below the OSHA (Occupational Safety and Health Act) limits.
Base Station Antenna minimum safe distance: 7.9 inches (20 cm) at 100% duty cycle.
Base Station Antenna gain: This device has been designed to operate with an antenna having a maximum gain of up to 2dBi.
Antenna mounting: The antenna(s) used for the base transmitter must be installed to provide a separation distance of at least
7.9 inches (20 cm) from all persons and must not be co-located or operating in conjunction with any other antenna or transmitter.
Antenna substitution: Do not substitute any antenna for the one supplied by the manufacturer or radio dealer. You may be
exposing person or persons to excess radio frequency radiation. You may contact your radio dealer or the manufacturer for further
instructions.
WARNING: Maintain a separation distance from the Base Station transmit antenna to a person(s) of at least 7.9 inches (20 cm) at
100% duty cycle.
You, as the qualified end-user of this radio device must control the exposure conditions of bystanders to ensure the minimum
separation distance (above) is maintained between the antenna and nearby persons for satisfying RF exposure compliance. The
operation of this transmitter must satisfy the requirements of Occupational/Controlled Exposure Environment, for work-related use.
Transmit only when person(s) are at least the minimum distance from the properly installed, externally mounted antenna.
This device complies with Industry Canada license-exempt RSS standard(s). Operation is subject to the following two conditions: (1)
this device may not cause interference, and (2) this device must accept any interference, including interference that may cause
undesired operation of the device.
Cet appareil est conforme avec Industrie Canada RSS standard exempts de licence (s). Son utilization est soumise à Les deux
conditions suivantes: (1) cet appareil ne peut pas provoquer d'interférences et (2) cet appareil doit accepter Toute interférence, y
compris les interférences qui peuvent causer un mauvais fonctionnement du dispositif.
This device complies with Health Canada’s Safety Code 6 / IC RSS-210. The installer of this device should ensure that RF radiation
is not emitted in excess of the Health Canada’s requirement. Information can be obtained at: http://www.hc-sc.gc.ca/ewhsemt/pubs/radiation/radio_guidelignes_direct-eng.php
Cet appareil est conforme avec Santé Canada Code de sécurité 6 / IC RSS-210. Le programme d'installation de cet appareil doit
s'assurer que les rayonnements RF n'est pas émis au-delà de l'exigence de Santé Canada. Les informations peuvent être obtenues:
Hereby, HM Electronics, Inc. declares that the DX121 is in compliance with the essential requirements and other relevant provisions of R&TTE Directive
1999/5/EC.
is product operates in the 2400 to 2483.5 MHz frequency range. e use of this frequency range is not yet harmonized between all countries. Some countries
may restrict the use of a portion of this band or impose other restriction relating to power level or use. You should contact your Spectrum authority to determine
possible restrictions.
Waste Electrical and Electronic Equipment (WEEE)
The European Union (EU) WEEE Directive 2012/19/EU places an obligation on producers (manufacturers, distributors and/or
retailers) to take-back electronic products at the end of their useful life. The WEEE Directive covers most HME products being
sold into the EU as of August 13, 2005. Manufacturers, distributors and retailers are obliged to nance the costs of recovery from
municipal collection points, reuse, and recycling of specied percentages per the WEEE requirements.
Instructions for Disposal of WEEE by Users in the European Union
The symbol shown below is on the product or on its packaging which indicates that this product was put on the market after
August 13, 2005 and must not be disposed of with other waste. Instead, it is the user’s responsibility to dispose of the user’s
waste equipment by handing it over to a designated collection point for the recycling of WEEE. The separate collection and
recycling of waste equipment at the time of disposal will help to conserve natural resources and ensure that it is recycled in
a manner that protects human health and the environment. For more information about where you can drop off your waste
equipment for recycling, please contact your local authority, your household waste disposal service or the seller from whom you
purchased the product.
Base Station
Power
DX121Quick Reference Guide
¾ Connect power ― See page 8
¾ Press POWER button to turn base station on/off ― Red light above button indicates power on
¾ BATT PWR light (not used in this product)
Beltpac and
Headset
Registration
IC/ISO
Indicators
Headset / 4-Wire
Audio Level
Battery Charger
Mode
Setup
¾ Insert a charged battery
¾ Press REG button on the base station to enter registration mode ― See page 12
¾ Hold down ISO button while you press and release POWER button on the headset or beltpac
¾ Green lights indicate IC or ISO communication is being received
¾ Adjust INbound/OUTbound headset and 4-Wire equipment audio levels using small screwdriver
¾ Place battery in port for charging
¾ Red CHG light indicates battery is charging
¾ Green RDY light indicates fully-charged battery is ready
BeltpacHeadset
Hands Free (HF)Push-To-Talk (PTT)ISO Lockout
¾ Power OFF
¾ Power OFF
¾ Press/hold
you press/release
and while
¾ Power OFF
¾ Press/hold
you press/release
and while
¾ Press/hold
press/release
To reset ISO ―
while you
¾ Release and
¾ Press and release or
quickly to latch into mode to
Operation
Change Battery
For detailed information on DX121 features, and for setup and operating instructions, continue reading the following pages.
talk to other users
¾ Press/release again to
unlatch and listen
If you hear “Change battery” ―
¾ Remove battery from beltpac
¾ Place battery in battery-charger port
for recharging
¾ Install fully charged battery in beltpac
¾ Release
¾ Press and hold or
while talking to other users
¾ Release to listen
and
¾ Press/hold and
you press/release
¾ Use either or to talk
to other users in HF or PTT
will not operate relay
¾
while
1
SECTION 1. INTRODUCTION
The DX121 is a 2.4 GHz Wireless Intercom System. The Base Station will connect to a dynamic microphone headset jack or the
4-Wire connector of a hardwired intercom station. It also provides battery-charging capability for one battery. The system typically
uses BP200 Beltpacs, but it can also be used with the WH220 All-in-One Headset. Once connected to your system, you can leave
your console or intercom station while using a beltpac or headset.
¾ Each Base Station supports one beltpac or headset in full duplex, hands-free operation.
¾ Each Base Station supports up to four registered beltpac or headset.
¾ Compatible with RTS and ClearCom/Production Intercom wired intercom headset or 4-Wire capable equipment.
NOTE: Use only with headset connectors capable of supporting dynamic microphone headsets.
¾ In the default mode, the ISO button activates relay-controlled contacts. For alternate operating mode, see Relay Operation
on page 16.
¾ The IC button activates audio to the 4-Wire and headset Input/Output connector(s).
¾ The ISO and IC buttons activate audio to other registered beltpacs and headsets.
¾ The Base Station can charge a BAT41 battery in less than 3 hours.
Typical DX121 Applications
Large Venue
2
Radio Communication Center
Broadcasting
Theater
3
Equipment Identication
The DX121 One-to-One Wireless Intercom System includes a base station and may include any combination of beltpacs and headsets.
Other optional equipment may also be used with your system. As you unpack the equipment, check the enclosed shipping document to
be sure you received all items listed.
Base Station
BS121 Base Station
Beltpac and Headset
CC-15-MD4 HeadsetBeltpac Pouch
BP200 Beltpac
Base Station Antennas
(2 per Base Station)
115/230 Volt AC Power Supply
(1 per Base Station, with Power Cord)
WH220 All-in-One
Wireless Headset
Battery (BAT41)
Two per Beltpac or All-in-One Headset
Battery (BAT50)
Two per Beltpac or All-in-One Headset
AC50 Battery Charger
NOTE: If you’re using a WH220 with the
MB121, you will need to purchase AC50
battery charger.
10. HEADSET and 4W (4-Wire) IN and OUT
audio level controls
11. Battery charger port (BAT41 battery only)
12. RDY (battery ready) light
13. CHG (battery charging) light
Rear Panel
14. Antenna connector
15. 12-14 VDC power supply connector
16. Antenna connector
17. HEADSET / 4-WIRE connector block
18. PRI SEC (primary/secondary) switch
19. RELAY connector block
5
Beltpac Features
1. Headset cable connector
2. Beltpac power and transmit lights
3. ISO (Isolate) button
4. IC (Intercom) button
5. PWR (Power) button
WH220 Headset Features
6. Volume-up button
7. Volume-down button
8. Battery
9. Battery release latch
1. IC1 button
2. ISO (Isolate) button
3. Volume-up button
4. IC2 button
5. Volume-down button
6. Power/mode lights
7. Microphone
8. Power button
9. Battery
10. Battery-release latch
6
SECTION 2. BASE STATION SETUP
Basic Base Station Setup
The following description is for a basic, stand-alone DX121 One-to-One Wireless Intercom System setup. Intercom headset,
4-Wire intercom and relay connections are described on page 16.
Set up the Base Station as follows:
Approximate
90° angle
Antenna connectors
Rear Panel
12-14 VDC power connector
Power light
Front Panel
Power button
1. Mount antennas -
Mount the two enclosed antennas on the antenna connectors on the rear panel of the Base Station. Position the antennas at an
approximate 90° angle. Turn the sleeve on each of the antenna connectors clockwise to tighten it securely in place.
2. Connect power -
¾ Plug the connector at the end of the AC power supply cord into the 12-14VDC power connector on the rear panel of the
Base Station, and turn the nut on the connector clockwise to secure it to the Base Station.
¾ Plug the female connector at one end of the power cord into the AC power supply, and plug the other end into an electrical
outlet.
¾ Press the POWER button on the front of the Base Station to turn it on. The red light above the button should turn on.
Power supply
To electrical outletPower cord connector
connector
Base Station rear panel
AC power supply Power cord
7
3. Charge batteries -
IMPORTANT! – Before using the DX121 system, charge the batteries for the Beltpacs and/or WH220 Headsets. Charging time
for fully-discharged batteries is about 3 hours per battery.
¾ One battery can be charged in the battery
charger at a time.
¾ Insert a battery in the charging port until it
clicks in place.
¾ A red charging CHG light above the battery
port stays on while a battery in the port is
charging.
¾ A green ready RDY light above the battery
port goes on when a battery in the port is
fully charged.
Green battery- ready light
Red battery- charging light
Battery
AC50 Battery Charger Setup
The AC50 is the charger for All-in-One headsets.
Before installing the system, connect the AC power supply to the battery charger
and plug it into an electrical outlet. Charge all the batteries while the other
equipment is being installed. Charging time is about 2.5 hours.
Connect AC Power Supply
To connect the AC power supply to the battery charger:
¾ Connect the AC power supply cable connector to the power connection
on the battery charger.
¾ Connect the AC power cord to an electrical outlet.
The red lights on the charger will briey display, and then the yellow lights will
appear and remain on.
Charging the Batteries
Up to four batteries can be charged in the battery charger at one time. The battery status lights next to each charging port indicate
the battery status. Up to four fully charged batteries can be stored in the battery Storage ports. Insert a battery in each of four
Charging ports until it clicks in place.
¾ A yellow light next to a Charging port indicates that the port is EMPTY.
¾ A red light next indicates that the battery port is CHARGING.
¾ A green light indicates that the battery is READY.
¾ A steady yellow light indicates that the CHARGE
FAILED. If a charge fails, refer to the instructions
on the side of battery charger.
¾ A ashing yellow light next indicates CHARGE
PENDING, which means the inserted battery is
too hot. Adjust the room temperature or move the
charger to a cooler area.
¾ Store fully charged batteries in storage ports.
IMPORTANT: Batteries should not be left in charge ports
after being fully charged. A battery left in a charging
port for more than three weeks may display the yellow
indicator light, but it does not indicate a faulty battery.
8
Interference Avoidance
Interference, which may be heard in a headset as popping sounds, may occur whenever other equipment such as WI-FI systems,
wireless DMX systems, other HME Base Stations are using the same frequency band. If these systems can be limited to one
portion of the band, then the DX121 can be set to the opposite half of the 2.4 GHz to 2.48 GHz band. To avoid this type of
interference, set up the base stations for “split-band” operation by selecting the upper part of the frequency range on one Base
Station (or more) and the lower part of the frequency range on the other(s). Here’s how:
1. Turn on the Base Station power. An “8” will appear on the STATUS display for a few seconds.
2. Once the “8” disappears and the STATUS display is blank, press and hold the CLR/BND button.
3. While holding the CLR/BND button, press and hold the REG button and wait until a L, H or A appears, and then release
both buttons.
4. Press the CLR/BND button to cycle through and select a frequency band: L = Low end,
H = High end and A = All.
5. Wait until “c” appears on the display.
NOTE: Base stations are shipped in the A (default) position.
Multiple Base Station Setup
This mode of operation can be used to expand the number of users communicating through multiple HME Base Stations operating
in the same portion of the 2.4 GHz to 2.48 GHz frequency band.
Primary and Secondary Base Station Settings
One Base Station must be designated as “Primary” while the others are designated as “Secondary”. You can have only one
primary and up to 3 secondary Base Stations. Secondary Base Stations are assigned numbers 1, 2, or 3.
1. Label the Base Stations as Primary, 1, 2 and 3.
2. Start with every Base Station and beltpac/headset powered off.
3. Locate the PRI SEC switch on the rear panel of the Base Station.
4. Set the PRI SEC switch to the PRI position on the primary Base Station.
5. Set the PRI SEC switch to the SEC position on each secondary Base Station.
6. If a Base Station has been set for interference avoidance, it should be used as the primary Base Station. The secondary
Base Stations will automatically be set to the same band when they are initialized.
PRI SEC
switch
Rear panel of Base Station
9
Base Station Initialization
For multiple HME Base Stations to operate without interference, they must be properly initialized before performing any other
setups. After initializing each Base Station, register each beltpac or headset that will be used with that base according to the
procedures on pages 12 – 15.
NOTE: Base stations must be set up for split-band operation prior to initialization.
(See Interference Avoidance on page 9.)
1. Turn the primary Base Station power on. Register any beltpacs or headsets to be used with the primary Base Station (See
pages 12 – 15). Turn each beltpac or headset off after registering it.
2. Power on one secondary Base Station. The STATUS display will show a double bar, indicating the secondary base is
ready to be initialized.
Double bar
Base Station ready to be initialized
Small “o” indicates primary
Small “o”
base is open for registration
3. Press the REG button on the primary base. The STATUS display will show a small “o”.
4. To assign a number to a secondary Base Station and then initialize it, repeatedly press the REG button on the secondary
base to cycle through the numbers 1, 2, and 3. When the desired number appears, stop pressing and wait.
5. While the secondary base initializes to the displayed number, the STATUS display will continue showing the secondary
number selected. When initialization of the secondary Base Station is nished, one bar is displayed that indicates that the
secondary has initialized to the primary.
Secondary base number
One bar
Secondary 2 searching for primarySecondary is initialized to primary
6. Press the REG button on the primary. The STATUS display will go blank.
7. Register beltpacs or headsets to the secondary (See pages 12 – 15). After registration, turn off the secondary base and all
Beltpac and headsets.
10
8. Repeat these steps for each remaining secondary base. Use a different number for each. Only the primary base and the
secondary base you are working with should have power on during initialization. All other equipment should be off.
9. After all secondary bases are initialized with beltpacs and headsets registered, power up all bases.
10. Press RESET on the primary base, and let it recover. Turn on the primary beltpacs or headsets to allow them to link.
11. Press RESET on each secondary base (one at a time), and let it initialize to the primary (indicated by a single bar).
12. Turn on the beltpacs or headsets associated with the secondary bases. Complete one group at a time until they have all
linked, then move on the next group. At this point all bases and beltpacs or headsets should be powered up and linked,
ready for use.
13. Proceed with normal system conguration, setting functions and levels as required.
Replacing a Secondary Base
Use the procedure above to initialize the new secondary with the same number as the old secondary. After initialization you
will have to register any Beltpacs/Headsets associated with the old secondary to the new secondary.
Replacing a Primary Base
Follow the above procedure completely. Before initialization of the secondary bases, clear the previous secondary initialization
as follows:
For each secondary, press the CLR/BND button and the RESET button simultaneously. Continue holding the CLR/BND
button while releasing the RESET button until the clear code (“c”) appears on the STATUS display. Any beltpacs or headsets
associated with the old primary will have to be registered to the new primary after secondary base initialization. Also, all
beltpacs and headsets associated with secondary Base Stations must be registered again.
Primary Base is Shut Down or Powered Off for More than 30 Seconds
All secondary bases will drop their beltpac and headset connections and begin searching for the primary. If the primary is
not found in 30 seconds, the secondary will automatically revert to primary-mode operation and reconnect the beltpacs or
headsets.
At this point, the secondary STATUS displays will show three bars. If the primary powered on, it will be necessary to press
RESET on all secondary bases to allow them to nd and initialize to the primary again. It’s important to have all bases
connected to the same AC circuit to prevent this situation when the system is shut down after hours and powered up again the
next day.
Three bars
Secondary base operating in primary
mode when no primary base is found
NOTE: You cannot register beltpacs and headsets to a base that is set to primary mode, and then switch the base mode to
secondary for initialization. Once in secondary mode, the base cannot recognize the beltpacs and headsets registered during
primary operation. For secondary bases, the beltpacs and headsets must always be registered after secondary base initialization,
with the primary base remaining active and the secondary base displaying one bar.
11
Beltpac / All-In-One Headset Setup and Registration
The rst time you operate the DX121 system, you must register each BP200 Beltpac and/or WH220 All-In-One Headset for use
with a specic Base Station. The Base Station will then recognize all registered beltpacs and headsets when their power is on and
differentiate between them and other electronic equipment operating on the same frequencies. If a beltpac or headset is added,
replaced or repaired later, the new one must be registered and the replaced one remains in memory. A maximum of 4 beltpacs
and headsets can be registered to a single Base Station at one time. If the maximum number of 4 is exceeded, you must clear all
current registrations and re-register all active beltpacs and headsets.
NOTE: The following two pages are for Beltpac setup and registration. All-In-One Headset setup and registration instructions are
on pages 14 and 15.
Set Up Beltpacs
Before registering them, set up all Beltpacs as follows:
1. Insert a fully charged battery in the Beltpac,
with the metal contacts on the end of the
battery inserted rst. Press it in until it snaps.
2. Place the Beltpac in the pouch.
3. Plug the headset cable connector into the
Beltpac.
Step 1
Register Beltpacs
Beltpacs must be within 6 feet (1.83 meters) of the Base Station during registration. Before
you begin, be certain the Base Station power is on and each Beltpac to be registered is
turned off. Registered Beltpacs can be on or off.
NOTE: If you are setting up multiple Base Stations, the following steps must be
repeated for Beltpacs being registered to each Base Station.
1. Place the headset of the Beltpac being registered on your head.
Step 3
Step 2
6
4
2. Press the REG button on the front panel of the Base Station (#6 on Base Station
front panel illustration).
●The STATUS display (#4 on Base Station front panel illustration) will show a
small “o” for open.
NOTE: If you wait too long before going on to Step 3, the Base Station will exit
registration mode and you will have to repeat Step 2.
3. Press and hold the ISO button on the Beltpac while you press and release the
PWR (power) button to turn the unit on, then release the ISO button. This will cause
the Beltpac to enter the registration mode.
●The two power lights at the corners of the Beltpac near the IC and ISO buttons
will blink red, then blink green two or three times and turn off.
●Wait! There may be a short delay.
0
12
If registration is successfully completed:
¾ A voice message in the headset will say “Power on, Beltpac #, Version #, Begin registration, Registration complete, …”
¾ After a delay of up to 15 seconds, the STATUS display will show the ID number assigned to this Beltpac for about 10
seconds.
NOTE: ID numbers are assigned sequentially as 0 through 3.
¾ The power light on the Beltpac, next to the IC button, will remain on steady green.
¾ Repeat Steps 1 to 3 at the bottom of page 12 for each Beltpac to be registered.
If registration failed:
¾ A voice message in the headset will say “Power on, Beltpac #, Version #, Begin registration, …” Both power lights on the
Beltpac will be blinking red, and there may be a delay of up to 90 seconds before you hear “Registration failed” and the
STATUS display (#4) goes blank.
¾ Press RESET (#7) on the Base Station. To press RESET, insert a small paper clip or similar object into the RESET hole
at the lower-left corner of the Base Station front panel. When the STATUS display (#4) becomes blank, press the REG
button (#6) and register the Beltpac again. If registration fails again, call your dealer for assistance.
6
4
7
F
If you try to register more than 4 devices (combination of beltpacs or headsets) to a Base Station:
¾ An “F” (for registration “Full”) will appear on the STATUS display (#4) on the Base Station and you will hear “Registration
failed” in the Headset.
¾ Clear all current registrations by pressing the CLR/BND button (#5) and RESET (#7) simultaneously. To press RESET,
insert a small paper clip or similar object into the RESET hole at the lower-left corner of the Base Station front panel.
Continue holding the CLR/BND button after you release RESET, until the clear code “c” (lower case) appears on the
STATUS display.
¾ Register all active Beltpacs, one at a time.
5
C
13
Set Up All-In-One Headsets
Before registering them, insert a fully charged battery in each Headset. When a
battery weakens, you will hear “Change battery”. At this time, remove the battery
from the headset by pressing the blue battery-release latch to remove the battery.
Power On/Off
¾ To turn power on
Press and release the power button on the inside of the Headset housing.
A voice message in the earpiece will say “Headset #” and the power light
on the opposite side of the earpiece will turn on.
¾ To turn power off
Press and hold the power button for approximately 3 seconds. A voice
message in the earpiece will say “Headset off”, and the power light on the
opposite side of the earpiece will go off.
Power
Light
Power button
Battery-release latch
(blue button)
Battery
Register All-In-One Headsets
Headsets must be within 6 feet (1.83 meters) of the Base Station while you are registering them. Be certain the Base Station
power is on, and each Headset you are going to register is turned off before you begin. Headsets that are already registered can
be on or off.
NOTE: If you are setting up multiple Base Stations, the following steps must be repeated for Headsets being registered to each
Base Station.
1. Put the Headset on your head.
6
2. Press the REG button on the front panel of the Base Station (#6 on Base Station
front panel illustration).
●The STATUS display (#4 on Base Station front panel illustration) will show a
small “o” for open.
NOTE: If you wait too long before moving to Step 3, the Base Station will exit
registration mode and you will have to repeat Step 2.
3. Press and hold the ISO button on the Headset while you press and release the
power button to turn the unit on, then release the ISO button. This will cause the
Headset to enter registration mode.
●The Headset power light will begin blinking red, then will blink green two or
three times and go off. There may be a short delay.
o
4
14
If the registration is successfully completed:
¾ A voice message in the Headset will say “Power on, Headset #, Version #, Begin registration, Registration complete, …”
¾ After a delay of up to 15 seconds, the STATUS display will show the ID number assigned to this Headset for about 10
seconds.
NOTE: ID numbers are assigned sequentially as 0 through 3.
¾ The power light on the Headset will remain on steady green.
¾ Repeat Steps 1 to 3 at the bottom of page 14 for each Headset to be registered.
If registration failed:
¾ A voice message in the Headset will say “Power on, Headset #, Version #, Begin registration, …”. The power light on the
Headset will be blinking red, and there may be a delay of up to 90 seconds before you hear “Registration failed” and the
STATUS display (#4) goes blank.
¾ Press RESET (#7) on the Base Station. To press RESET, insert a small paper clip or similar object into the RESET hole
at the lower-left corner of the Base Station front panel. When the STATUS display (#4) becomes blank, press the REG
button (#6) and register the Headset again. If registration fails again, call your dealer for assistance.
6
4
F
If you try to register more than 4 devices (combination of beltpacs or headsets) to a Base Station:
¾ An “F” (for registration “Full”) will appear on the STATUS display (#4) on the Base Station and you will hear “Registration
failed” in the Headset.
¾ Clear all current registrations by pressing the CLR/BND button (#5) and RESET (#7) simultaneously. To press RESET,
insert a small paper clip or similar object into the RESET hole at the lower-left corner of the Base Station front panel.
Continue holding the CLR/BND button after you release RESET, until the clear code “c” (lower case) appears on the
STATUS display.
¾ Register all active WH220 Headsets, one at a time.
5
7
C
NOTICE
You have completed the system setup.
The instructions under INTERCOM AND RELAY CONNECTIONS on the next page are for setting up auxiliary audio equipment
which you may want to use with your DX121.
15
Intercom and Relay Connections
If using your DX121 with a wired intercom system, connect the intercom to the HEADSET/4-WIRE connector on the rear panel
of the Base Station as shown below. Also, the RELAY connector shown below can be used as a “dry contact” for any outside
equipment.
Base Station rear panel showing HEADSET/4-WIRE and RELAY connectors
Base Station front panel showing HEADSET and 4W (4-Wire) input and output level adjustments
HEADSET/4-WIRE Connector
Pin 1
Pin 2SPKR + Input
Pin 3MIC – Output
Pin 4MIC + Output
Pin 5N/C
Pin 6GND
Pin 7
Pin 84-WIRE + Output
Pin 94-WIRE – Input
Pin 104-WIRE + Input
Headset
connections
4-Wire
connections
SPKR – Input
4-WIRE – Output
NOTE: Indicated
PinOut connections
should be matched
to the corresponding
PinOut connections
of the intercom
which will be used.
RELAY Connector
Pin 1 N.C. (Normally Closed)
Pin 2 COM
Pin 3 N.O. (Normally Open)
Pin 4 IC SEL
Pin 5 GND
Intercom Headset Connection
If using the headset connector of an intercom, connect the wires from a headset connector (not provided) to pins 1 through 4 of
the HEADSET/4-WIRE connector on the rear panel of the Base Station. Be sure the headset jack of the intercom system is turned
on. For intercom headset wiring diagram, see page 28.
4-Wire Intercom Connection
If using a 4-Wire intercom, connect the wires from a 4-Wire connector into the HEADSET/4-WIRE connector on the rear panel of
the Base Station. For 4-Wire wiring diagram, see page 28.
Relay Operation
In the default mode, the relay will operate only when the ISO button is pressed. In the IC SEL mode, the relay will operate only
when the IC button is pressed. With either mode, the IC button activates audio to the HEADSET/4-Wire IN/OUT connector. The IC SEL mode is selected by placing a jumper across pins 4 and 5 of the RELAY connector.
16
SECTION 3. EQUIPMENT OPERATION
Base Station Operation
Front Panel Controls, Indicators and Connector
1. Power button
Press the POWER button to turn the power on. A red light above the button will be lit when the Base Station power is on.
Press the button again to turn the power off. The light will go off. All settings are preserved when the power is turned off,
and will be restored when the power is turned on again.
2. Registration Controls and Status Indicator
Use these controls to register each Beltpac, All-In-One Headset and/or Speaker Station beltpac or headset used with a
specic Base Station.
STATUS display – the status of beltpacs and headsets as they are being registered to the Base Station
REG button – is used to set the Base Station in registration mode, so registration can begin
CLR/BND button / RESET switch – when used together, clear all registrations from the Base Station
3. IC (Intercom) and ISO (Isolate) Receiver Indicators and Controls
Green lights indicate whether IC or ISO is being received.
4. Adjustments
Use a screwdriver to adjust the HEADSET and 4W IN (input) and OUT (output) levels.
5. Indicators
POWER – When the DC power is on, the red POWER light will be lit.
CHG – When the battery is charging, the red CHG light will be lit.
RDY – When the battery is fully charged, the green RDY light will be lit.
17
Beltpac Operation
The Beltpac control buttons have a snap action. They will activate when pressed rmly. Use your ngertips, not your ngernails, to
press the buttons.
Power On/Off
¾ Power On — Press and release the PWR (power) button.
A voice message in the earpiece will say “Power on, Beltpac #, Version #”, and the red
power lights at the corners of the IC and ISO buttons will turn on. After a short time,
one light will go off and the other will change to green indicating the Beltpac is ready for
use. The STATUS indicator on the Base Station will momentarily indicate the ID of the
Beltpac.
¾ Power Off — Press and hold the PWR button for approximately 2 seconds.
A voice message in the earpiece will say “Power off”, and the green power light will turn off.
NOTE: While the Beltpac is transmitting, the green power light will be ashing. The
green power light will be on steady whenever the Beltpac is ready, but not transmitting.
Power Lights
ISO and IC
Either the ISO or IC button can be used to talk to other beltpacs and headsets. IC will send the audio signal out to intercoms
through the HEADSET and 4-WIRE connections on the rear panel of the Base Station. Depending on your Base Station RELAY
operation setup (see page 16), either the ISO button or the IC button will activate any outside equipment connected to the RELAY
connector on the rear panel of the Base Station.
¾ Push-To-Talk Mode — To set the Beltpac for push-to-talk (PTT) communication, with the power off, press and hold the
volume-down and ISO buttons while you press and release the PWR (power) button. You will hear “Power on, Beltpac
#, Version #, Hands-free off” in the headset. Press and hold the IC or ISO button while talking.
¾ Hands-free Mode — To set the Beltpac for hands-free communication, with the power off, press and hold the volume-up
and ISO buttons while you press and release the PWR (power) button. You will hear “Power on, Beltpac #, Version #,
Hands-free on” in your headset. When set up for hands-free communication, the Beltpac can be operated in either handsfree or PTT.
¾ ISO Lockout Mode — To set the Beltpac with the ISO feature locked out, with the power off, press and hold the IC button
while you press and release the PWR (power) button. You will hear “Power on, Beltpac #, Version #, ISO off” in your
headset. When set up for the ISO Lockout mode, the ISO button will operate the same as the IC button, in either handsfree or PTT communication.
To reset the ISO feature for normal ISO button communication, with the power off, press and hold the ISO and IC buttons
while you press and release the PWR (power) button. You will hear “Power on, Beltpac #, Version #, ISO on” in your
headset.
NOTE: The above settings are saved in memory and only need to be repeated when you want to change between handsfree and PTT operation. When changing modes, if both power lights begin blinking, turn the Beltpac off and begin again.
Hands-free and Push-To-Talk mode settings affect both IC and ISO. Individual adjustment is not possible.
¾ Push-To-Talk Mode Operation — Press and hold the IC or ISO button while speaking. In PTT operation, audio will be
transmitted only while you are pressing the IC or ISO button.
¾ Hands-free Mode Operation — Quickly press and release the IC or ISO button to “latch” the transmitter on in the
hands-free mode. Talk and listen, as in a normal telephone conversation. Press and release the IC or ISO button again to
“unlatch”, to end the conversation. If either button is held down for more than a half second, the Beltpac will function as
PTT.
NOTE: In hands-free mode, pressing the IC button while latched in ISO will latch on IC. Pressing the ISO button while
latched in IC will latch on ISO.
18
Volume Up/Down
¾ Volume Up Adjustment — Each time you press and release the volume-up button, you will hear a higher pitch beep
in the earpiece as the volume increases one step. If you press and hold the volume-up button, you will hear beeps of
ascending pitch as the volume steps up to maximum. When maximum volume is reached, you will hear “maximum”
repeating until you release the volume-up button.
¾ Volume Down Adjustment — Each time you press and release the volume-down button, you will hear a lower pitch
beep in the earpiece as the volume decreases one step. If you press and hold the volume-down button, you will hear
beeps of descending pitch as the volume steps down to minimum. When minimum volume is reached, you will hear
rapidly repeating beeps until you release the volume-down button.
Sidetone Adjustment
To adjust sidetone (the volume level of your own voice heard in the headset as you speak into the microphone), press and hold
the IC button while you press the volume-up or volume-down button.
If you reach the maximum volume level, you will hear “Maximum” in the headset. If you reach the minimum volume level you will
hear double beeps. Your sidetone setting will be saved in memory, and does not require readjustment each time the Beltpac is
turned off and on.
NOTE: This adjustment only affects the level of your voice in your own headset, not how anyone else hears you.
Microphone Gain Adjustment
Some users talk louder or softer than others. To allow for this, microphone gain adjustment is provided.
To increase microphone gain — Press the volume-up button while holding down the ISO button in the normal operating
mode. The microphone gain increase can be monitored through sidetone, or preferably by someone else or at the Base Station.
To decrease microphone gain — Press the volume-down button while holding down the ISO button in the normal operating
mode. The microphone gain decrease can be monitored through sidetone, or preferably by someone else or at the Base Station.
NOTE: You will hear “Maximum” if you attempt to go higher than maximum microphone gain. You will hear beeps if you
attempt to go lower than minimum microphone gain. Microphone gain will be saved in non-volatile memory and does not
require readjustment each time the power is turned on.
Change Batteries
When a battery becomes weak, a voice in the earpiece will say “Change battery”. When this happens, take the Beltpac out of its
pouch and remove its battery. Slide the arrow-shaped battery-release latch in the direction of the arrow. Pull up on the end of the
battery near the battery-release latch and lift the battery out of the Beltpac, or turn the Beltpac over and catch the battery in your
hand.
When replacing a battery in the Beltpac, place the end of the battery with the metal contacts into the battery holder on the Beltpac,
in the same position as the battery you removed. Press the top of the battery carefully into the battery holder until it snaps in place
under the battery-release latch. Recharge batteries according to the instructions on page 8.
Battery
Battery-release latch
(blue button)
19
All-In-One Headset Operation
The Headset control buttons will activate when pressed lightly. Use your
ngertips, not your ngernails, to press the buttons.
Power On/Off
¾ Power On — Press and release the power button on the inside of the
Headset housing. A voice message in the earpiece will say “Power on,
Headset #, Version #” and the power light will turn on. The STATUS
indicator on the Base Station will momentarily indicate the Headset ID
number.
¾ Power Off — Press and hold the power button for approximately 3
seconds. A voice message in the earpiece will say “Power off”, and
the power light will go off.
ISO and IC
The ISO, IC1 or IC2 buttons can be used to talk to others. IC will send the audio signal out to
intercoms through the HEADSET and 4-WIRE connections on the rear panel of the Base Station.
Depending on your Base Station RELAY connection setup (see page 17), either the ISO button or
the IC button will activate any outside equipment connected to the RELAY connector on the rear
panel of the Base Station.
¾ Push-To-Talk Mode — To set the Headset for Push-To-Talk (PTT) communication, with
the power off, press and hold the volume-down and ISO buttons while you press and
release the power button. You will hear “Power on, Headset #, Version #, Hands-Free off”
in the earpiece. Press and hold the IC1, IC2 or ISO button while talking.
Power button
Power Light
¾ Hands-Free Mode — To set the Headset for Hands-Free (HF) communication, with the
power off, press and hold the volume-up and ISO buttons while you press and release
the power button. You will hear “Power on, Headset #, Version #, Hands-Free on” in the
earpiece. When set up for Hands-Free communication, the Headset can be operated in
either HF or PTT.
¾ ISO Lockout Mode — To set the Headset with the ISO feature locked out, with the power
off, press and hold the IC1 button while you press and release the power button. You will hear “Power on, Headset #,
Version #, ISO off” in your Headset. When set up for the ISO Lockout mode, the ISO button will operate the same as the
IC1 button, in either hands-free or PTT communication. To reset the ISO feature for normal ISO button communication,
with the power off, press and hold the ISO and IC1 buttons while you press and release the power button. You will hear
“Power on, Headset #, Version #, ISO on” in your Headset.
¾ Lights-off Mode — To prevent the power and transmit lights from coming on during headset operation, press and hold
the IC2 button while you press the power button to turn the headset on. To return the lights to their normal functions, turn
the power off and on again without pressing the IC2 button.
NOTE: The above settings are saved in memory and only need to be repeated when you want to change between HF
and PTT operation. When changing modes, if both power lights begin blinking, turn the Headset off and begin again.
Hands-Free and Push-To-Talk mode settings affect both IC and ISO. Individual adjustment is not possible.
¾ Push-To-Talk Mode Operation — Press and hold the IC1, IC2 or ISO button while speaking. In PTT operation, audio will
be transmitted only while you are pressing the IC1, IC2 or ISO button.
¾ Hands-Free Mode Operation — Quickly press and release the IC or ISO button to “latch” the transmitter on in the HF
mode. Talk and listen, as in a normal telephone conversation. Press and release the IC or ISO button again to “unlatch”,
to end the conversation. If either button is held down for more than a half second, the Headset will function as PTT.
NOTE: In Hands-Free mode, pressing the IC1 or IC2 button while latched in ISO will latch on IC. Pressing the ISO button
while latched in IC will latch on ISO.
20
Volume Up/Down
¾ Volume Up Adjustment — Each time you press and release the volume-up button, you will hear a higher pitch beep
in the earpiece as the volume increases one step. If you press and hold the volume-up button, you will hear beeps of
ascending pitch as the volume steps up to maximum. When maximum volume is reached, you will hear “maximum”
repeating until you release the volume-up button.
¾ Volume Down Adjustment — Each time you press and release the volume-down button, you will hear a lower pitch
beep in the earpiece as the volume decreases one step. If you press and hold the volume-down button, you will hear
beeps of descending pitch as the volume steps down to minimum. When minimum volume is reached, you will hear
rapidly repeating beeps until you release the volume-down button.
Microphone Gain Adjustment
Some users talk louder or softer than others. To allow for this, microphone gain adjustment is provided.
To increase microphone gain — Press the volume-up button while holding down the ISO button in the normal operating
mode. The microphone gain increase can be monitored through sidetone, or preferably by someone else or at the Base Station.
To Decrease microphone gain — Press the volume-down button while holding down the ISO button in the normal operating
mode. The microphone gain decrease can be monitored through sidetone, or preferably by someone else or at the Base Station.
NOTE: You will hear “Maximum” if you attempt to go higher than maximum microphone gain. You will hear two beeps if
you attempt to go lower than minimum microphone gain. Microphone gain will be saved in non-volatile memory and does
not require readjustment each time the power is turned on.
Change Batteries
When a battery becomes weak, a voice in the Headset will say “Change battery”. When this happens, remove the battery from the
headset by carefully sliding the battery-release latch and lifting the battery out.
When replacing a battery in the Headset, place the end of the battery with the metal contacts into the battery holder on the
Headset, in the same position as the battery you removed. Press the top of the battery carefully into the battery holder until it
snaps in place under the battery-release latch.
Recharge batteries according to the instructions on page 8.
Battery-release latch
(blue button)
Battery
21
SECTION 4. TROUBLESHOOTING
If you are unable to correct any of the problems described below, contact your dealer for assistance.
PROBLEMSOLUTION
Power light on Base Station does not come on.Be certain power cords are properly connected to Base
Station, power supply and electrical outlet.
Beltpac or headset power lights do not turn green, and “out
of range” is heard.
When trying to register, it keeps saying registration failed.
Others cannot hear me when I talk.If you are using a Beltpac or local headset, be certain the
People on the 4-Wire intercom cannot hear me or I cannot
hear them.
People on the RTS/ClearCom systems cannot hear me or I
cannot hear them.
2400MHz cordless telephone interference — If there is a 2400MHz cordless telephone nearby,
interference may occur. However, because the DX121 is a frequency-hopping system, this problem is
unlikely. If it does occur, changing frequencies on the telephone may alleviate the problem. If not, move
the phone as far as practical from the Base Station, or use another type phone.
Be certain your Base Station power is on. Turn Beltpac or
headset and Base Station power on and off. You may be
too far from the Base Station. The range varies with each
location’s layout.
Check to be sure that the STATUS window only goes
blank, and does not show a registration number. Follow the
instructions on clearing the registrations as found on page 13
or 15, and repeat the registration procedure.
headset connector is correctly plugged in to the Beltpac or
Base Station.
Be certain the cables are securely connected and the 4-Wire
intercom is on.
Be certain the cables are securely connected and the 2-wire
intercom is on.
In the event of an electrical power outage — such as from a lightning storm or power generator
failure, if you experience problems with your HME equipment after the electricity comes on again,
unplug the AC power supplies from their electrical outlets and wait 15 seconds, then plug them back in.
22
SECTION 5. DX SERIES LED AID
Powering on any DX base station will produce on the LED display the number “8” for approximately 3 seconds.
Blank display indicates the base is ready for operation.
You can register belt packs under this condition.
Single horizontal bar indicates the base is in secondary mode and registering to a base has been initiated and
successfully linked with a primary base. You can register beltpacs in this mode.
Two horizontal bars indicate that the base is in secondary mode and ready to be synced with a primary base. You cannot register beltpacs in this mode you must sync to a primary base rst.
Three horizontal bars indicate the base is in secondary mode and has been linked with a primary base but the primary
base is no longer available to the secondary. It takes a few seconds for the secondary to recognize that the primary is
not available and revert to a primary state. However, you can register belt packs under this condition.
Syncing Secondary to Primary Bases Feature
To sync the bases, perform the following steps:
¾ Press the REG or REGISTER BELT-PAC* button on the primary base and then press the REG or REGISTER BELT-PAC*
button on the secondary base to begin the sync process.
¾ As you repeatedly press the REG or REGISTER BELT-PAC* button on the secondary you will see the numbers 1, 2,
and 3 cycle through on the display. The numbers indicate the three available quadrants. Note: The primary is in the 0 quadrant by default.
¾ To select a quadrant, simply release the button at a desired number and wait. If successful, you will briey see a blank
display followed by a single horizontal bar in the secondary LED display. For additional secondary bases, assign each
base to its own quadrant. Refer to the appropriate equipment manual for primary to secondary conversion.
After the bases are synced when the secondary is powered up the number “8” will appear followed by one of the numbers below
on the secondary base LED display:
The number “1” indicates the quadrant the secondary has been placed in.
The number “2” indicates the quadrant the secondary has been placed in.
The number “3” indicates the quadrant the secondary has been placed in.
NOTE
* Button has the same
function but with a
different description on the
equipment due to vintage.
23
The lower case “c” will appear when the registry on the base station is cleared. To clear the registry power down the
base. Hold down the CLR/BND or RESET REGISTRATION* button rst and then power the base on when you see the
“8” on the LED display release the CLR/BND or RESET REGISTRATION*. If done successfully you will see a small
"c" on the LED display.
NOTE: The display indicates that the registry of a base station has been cleared of all beltpacs and secondary
base stations that were registered to the base station.
Another method to clear the registry would be to start by holding down the CLR/BND or RESET REGISTRATION*
button rst and then pressing the RESET button until you hear a small click and then release the CLR/BND or RESET
REGISTRATION* button. If done successfully you will see a small "c" on the LED display. We recommend you use a
very small paper clip.
The lower case “o” will appear when the REG or REGISTER BELT-PAC* button is pressed and indicates that the base
is ready to register a beltpac.
When registering beltpacs on DX bases that can carry 15 beltpacs please note that the numeric count displayed on the LED will
be in hexadecimal. This means that the LED will represent the rst 10 beltpacs as 0 to 9. Beltpac 11 will be represented by the
letter A, beltpac 12 will be represented by the letter B and on up to beltpac 15 as E. Please see below.
Beltpac and Headset
Registry
The letter “F” will appear when the base registry is at its maximum of 15 registered belt packs. You will need to
clear the registry to add a beltpac. To clear the registry power down the base. Hold down the CLR/BND or RESET
REGISTRATION* button rst and then power the base on when you see the “8” on the LED display release the CLR/
BND or RESET REGISTRATION*. If done successfully you will see a small "c" on the LED display.
123456789101112131415
0123456789ABCDE
Spectrum Friendly Feature
Spectrum Friendly option: Hold down the CLR/BND (or RESET REGISTRATION*) button rst then press and hold down the
REG (or REGISTER BELTPAC*) button till you see the letter “A” or “L” or “H”. Then release both buttons and quickly press the
CLR/BND (or RESET REGISTRATION*) to cycle through the “A” or “L” or “H”. options. Stop at your selection and wait for the LED
display to go blank and a lower case c will appear on the status LED.
After this procedure is performed all bases, beltpacs and headsets will need to be re-registered to the base.
2400 to 2483.5 MHz is the operating frequency range.
2401.92 to 2439.94 MHz is the operating frequency range.
2443.39 to 2481.41 MHz is the operating frequency range.
NOTE
* Button has the same
function but with a
different description on the
equipment due to vintage.
24
SECTION 6. TECHNICAL DATA
DX121 Equipment Specications
BS121 Base Station
GENERAL
Frequency Range ...................... All, 2400 to 2483.5 MHz
Low, 2401.92 to 2439.94 MHz
High, 2443.39 to 2481.41 MHz
Frequency Response ................... 200 Hz to 3.5 kHz
Power Requirements .................... 100-240VAC, 50-60Hz or 12-14VDC
Temperature Range ..................... 32-122°F (0-50°C)
Size .................................. 1.62” x 5.50” x 7.88” (4.1 x 14 x 20 cm)
Weight ................................ 1.2 lbs. (.59 kg) with battery
# of Beltpacs per Base................... 4 can be registered
Only 1 can have full-duplex communication at a time
4-Wire I/O ............................. 600Ωbalanced, level adjustable, simultaneous operation with headset