Telex Audiocom US-2000 User manual

Telex®
Operating Instructions
US-2000
User Station
Audiocom®Intercom
System
®
US-2000
Mic Kill
Headset
PA
Panel Mic
Vox
SideTone
All Talk
Listen Listen
Call Call
12
Talk Talk
Volume
R

GENERAL
The Audiocom® US-2000 is a microprocessor controlled two-channel
intercom user station, that occupies only 1/2-rack space. The US-2000
can communicate with an entire intercom system or an individual
channel, and can be expanded up to 18 channels. ES-4000 Expansion
Stations can be “daisy chained” to the US-2000 to add four channels at a
time to the intercom system. Each channel can be programmed for talk,
listen or both. The US-2000 can use mono or stereo headsets, or panel
mounted microphone. VOX operation can be selected for either headset
or panel microphone. Internal switch and jumper settings allow the unit
to be used with Clear-Com® components, if desired. Other internal
switch and jumper settings allow the unit to be uniquely configured to the
operator’s requirements.
FCC STATEMENT
This equipment uses, and can radiate radio frequency energy that may
cause interference to radio communications if not installed in accordance
with this manual. The equipment has been tested and found to comply
with the limits of a Class A computing device pursuant to Subpart J, Part
15 of FCC Rules which are designed to provide reasonable protection
against such interference when operated in a commercial environment.
Operation of this equipment in a residential area may cause interference
which the user (at his own expense) will be required to correct.
This product meets the Electromagnetic Compatibility Directive,
89/336/EEC.
OPERATION
SYSTEM POWER
The US-2000 receives power externally, in one of two ways:
·Via the
12-15 VDC power input jack
·Via
CHN 1 or CHN 2 , intercom channel connectors
®Clear-Com is a registered trademark of Clear-Com Intercom Systems
® Audiocom is a trademark of Telex Communications, Inc., Minneapolis, Minnesota 55420
1

2
12-15 VDC
+
-
TELEX COMMUNICATIONS, INC. MADE IN USA
US-2000
4
5
17 13161514
123 6710108 9 12 12
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13
1
SPEAKERS
PROGRAM
INPUTS
2
LINE LEVEL
1 VRMS
P.A. EXP
OUT
Mic KillHeadset
PAPanel Mic
Vox
Side Tone
All Talk
Listen Listen
Call Call
12
Talk Talk
Volume
CHN 2
VOL
PGM 2
VOL
PGM 1
PUSH
CHN 1
11 11
PUSH
Figure 1. Front and Rear Panel Controls

INITIAL US-2000 SETUP
The channel termination is initially set for balanced operation, which is
compatible with other Audiocom® equipment. If the unit is going to be
connected to Clear-Com equipment, two jumpers and one switch must
be changed as described in the section on Clear-Com Setup in this
manual.
The US-2000 is factory set to allow all channels (including those of any
attached ES-4000 units) to be heard through a single powered speaker,
such as the Audiocom® SPK-1000. If the user wants to have each
channel go to a separate powered speaker, three jumpers must be
changed as described in the section on Speaker Setup in this manual.
The headset microphone termination is initially set for unbalanced
operation. To change the headset microphone termination, refer to
Table 2 in this manual for the position of jumper J16. If the termination
requirement of a headset microphone is unknown, the recommended
setting is unbalanced.
MICROPROCESSOR FUNCTIONS
RESET: Simultaneously press All Talk and channel 1 Listen keys to
reset the US-2000 microprocessor to its power-up state.
TEST SIGNAL: Simultaneously press
All Talk and PA keys to cause the
microprocessor to generate 1 kHz test signal. Press any US-2000 or
ES-4000
Call key to send the test signal down that channel. Press the
same
Call key to stop the test signal on that channel, then press any
other key on that unit (except
Call) to exit the test signal function.
EXTERNAL CONNECTIONS & CONTROLS
NOTE: The numbers refer to the callouts in Figure 1.
1. Mono Headset Connector
This connector accepts a Telex® boom-microphone headset.
2. Panel Microphone or Stereo Headset Connector
This connector accepts a Telex® gooseneck microphone (model
EGM-12N or EGM-18N) or stereo headset.
3

3. VOLUME Control
Use this control to adjust the headset listen level.
4.
SIDETONE Control
When using a headset, this control adjusts your own voice level
heard in the earphones. To adjust the level, tap the
Headset key
once to turn on the headset microphone. Then, use a small
flat-blade screwdriver to increase or decrease your voice level while
talking into the microphone.
5.
VOX Level Adjustment
There are separate
VOX level controls for headset and panel micro-
phone. These adjust the voice level required to activate the micro-
phone when VOX mode is on.
To adjust the headset VOX level, place the
Headset microphone key
in VOX mode (see 6 below). While talking into the headset micro-
phone in a normal voice, use a small flat-blade screwdriver to adjust
the
VOX control to the desired voice activation level. The Headset
microphone key will turn from orange to green as the microphone
turns on.
Use the same procedure to adjust the panel microphone VOX level
using the
Panel Mic key and VOX level control.
6.
Headset and Panel Mic keys
The
Headset key activates the headset microphone. The Panel Mic
key activates the panel microphone. Either key selects one of three
modes of microphone operation:
Latched Mode:
Tap the key once to turn the headset or panel microphone on.
The key will glow green. Tap the key again to turn the headset
or panel microphone off.
Momentary Mode:
Press and hold the key to momentarily turn on the headset or
panel microphone. Release the key to turn the headset or panel
microphone off.
4

VOX Mode:
With the headset or panel microphone off, tap the key twice to
turn on VOX mode. The key will glow orange when there is no
audio present, and green when you talk into the headset or
panel microphone. (When in VOX mode you may have to adjust
the
VOX level.) Tap the key once to turn off VOX mode.
7.
All Talk key
The All Talk function allows the user to talk on all attached channels
simultaneously. To activate this function with either the
Headset or
Panel Mic selected, press and hold the All Talk key to talk on all
US-2000 and ES-4000 channels at once. The key will glow green.
8.
PA key
The PA function allows the user to talk over a public address system
that is connected to the rear of the US-2000. With either the
Head-
set
or Panel Mic selected, press and hold the PA key to talk on a
public address system connected to the
P.A. output jack on the back
panel of the US-2000. The key will glow green.
9.
Mic Kill key
This key controls three features:
Microphone Kill Feature:
This feature sends a signal that causes the intercom stations on
a selected channel to turn off any activated microphones on that
channel. (Works with US-2000, ES-4000, SS-1000, BP1000 and
BP2000 stations.) Tap the key once to access this feature. The
key will blink green. To turn off all activated microphones on any
channel, press the
Talk or Listen key for the desired channels.
To turn off all microphones on all channels, press the
All Talk
key. Tap the Mic Kill key to exit.
Program Kill Feature:
This feature allows the program audio to be individually disabled
on each channel. Press and hold the key to access this feature.
The key will glow green and the current Program Kill status will
be displayed (when a
Talk key is lit, program audio is enabled on
that channel). Press a
Talk key to enable or disable program au-
5

dio on that channel. Tap the Mic Kill key to exit the feature
setup.
Headset Audible Call Alert Feature:
This feature will cause an audible beep in the headset whenever
there is an incoming call from any channel. Press and hold the
key to access this feature. The key will glow green and the cur-
rent Headset Audible Call Alert status will be displayed (when
both
Call keys are lit, Headset Audible Call Alert is enabled).
Press either
Call key to enable or disable Headset Audible Call
Alert on both US-2000 channels. Tap the
Mic Kill key to exit the
feature setup.
10.
Talk keys
There is a
Talk key for each channel. With either the Headset or
Panel Mic selected, the Talk keys operate in two ways:
Latched Mode:
Tap the key once to talk. The key will glow green. Tap the key
again when finished with a conversation.
Momentary Mode:
Press and hold the key to talk momentarily. Release the key
when finished talking.
11.
Call keys
The Call function allows the user to signal other devices on the inter-
com system. There is a
Call key for each channel. The Call keys
operate in two ways:
Call receive:
When there is an incoming call signal, the key blinks red. (If
Headset Audible Call Alert is enabled, incoming calls will cause a
beep in the headset.) To respond to an incoming call, turn on
the
Talk key for that channel and begin talking.
Call send:
To send a call signal to a station on a channel, press and hold
the
Call key until a verbal response is received. The Listen key
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for that channel automatically turns on when the Call key is
pressed.
12.
Listen keys
There is a
Listen key for each channel. The Listen keys operate in
two ways:
Latched Mode:
Tap the key once to turn on listen. Tap it again to turn off listen.
The key glows green when listen is on.
Momentary Mode:
Press and hold the key to listen momentarily. Release the key to
turn off listen.
13.
Program Inputs Connector and Program Volume Controls
In a television studio intercom system, the program input is usually
the actual program audio signal. In another intercom system, the
program input can be any auxiliary audio signal, such as background
music.
There is a separate program input for each channel (see Connector
Pin Configurations for connector details). The
VOL PGM 1 control
adjusts the program 1 level heard on intercom channel 1. The
VOL
PGM 2
control adjusts the program 2 level heard on intercom chan-
nel 2. As supplied, the US-2000 does not interrupt the program in-
puts during talk. Program interrupt during talk requires an internal
switch change (see Table 1, switches SW2-4 and SW2-5).
14.
12-15 VDC Input Jack
Normally the US-2000 is powered from the intercom system and will
turn on with the intercom system. The US-2000 may also be pow-
ered from an optional Telex® Wall Pack (part number 532006-000).
Plug the Wall Pack into the
12-15 VDC jack and into an AC outlet.
15.
P.A. Output Jack
To use the US-2000 with a public address system, connect this jack
to the input of the public address amplifier.
7

16.
EXP OUT Jack
Connects audio and data to the EXP IN jack of an optional Telex®
ES-4000 expansion station.
17.
SPEAKERS Output Jacks
Connects channel audio to the Input jacks of an optional Telex®
SPK-1000 Powered Speaker. May also be connected to the auxil-
iary input of an amplifier. These outputs should not be directly con-
nected to an unpowered speaker. Refer to the speaker setup
section in this manual.
18.
CHN 1 and CHN 2 Intercom Channel Connectors
Each intercom channel has a pair of connectors (one male and one
female) for convenient interconnection of stations. Each pair of con-
nectors is wired together in parallel, providing a “loop through” at
each connector pin. Use one connector of each pair to connect to
the intercom power supply. Use the other connector of each pair to
run a cable to another user station.
CHANNEL TERMINATION
Each channel of the US-2000 must be terminated to prevent audio
oscillations. When a channel is connected to a Telex® power supply,
channel termination is provided within the power supply for that channel.
External channel termination must be installed when a channel is:
·Used in a “dry-line” (non-powered channel) application
·Unused and un-powered
If necessary, install external channel termination by connecting a 300W
resistor across pins 2 and 3 of the intercom channel connector (either
CHN1 or CHN2 ) at the rear of the US-2000.
INTERNAL SWITCHES, JUMPERS AND ADJUSTMENTS
There are several internal switches, jumpers and adjustments that affect
operation. These are described below. To gain access to the switches,
jumpers and adjustments, remove one screw from the top of the cover
and two screws on each side. Switch, jumper and adjustment locations
8

are shown in Figure 2. The adjustments are also accessible from the
underside of the US-2000, as shown in Figure 3.
NOTE: To activate a changed switch or jumper setting, either
perform a RESET or cycle the power on and off.
9
SW1
SW2
J17
J19
J16
J8
R188 R187
R198
J21 J22
J23
J20
J7
J24
Figure 2. Internal Switches, Jumpers and Adjustments

Clear-Com Setup
Make the following switch and jumper changes when the US-2000 is
used with Clear-Com equipment:
·SW1 (BAL/UNBAL) must be placed in the UNBAL position.
·J17 (Clear-Com/Audiocom® Mic Level Select) must have pins 1 and
2 shorted.
·J21 (DC call enable/disable) must have pins 2 and 3 shorted.
Speaker Setup
Make the following switch and jumper changes to allow the audio from
each channel to go to separate powered speakers:
·J22 must have pins 1 and 2 shorted.
·J23 must have pins 1 and 2 shorted.
·J24 must have pins 2 and 3 shorted.
10
12-15 VDC
+
-
TELEX COMMUNICATIONS, INC. MADE IN USA
1
SPEAKERS
PROGRAM
INPUTS
2
LINE LEVEL
0.5 VRMS
P.A. EXP
OUT CHN2
VOL
PGM 2
VOL
PGM1
PUSH
CHN 1
PUSH
NO
ADJUSTMENT
LIMITER
CHN 1 RETURN
CANCELLATION
CHN 2 RETURN
CANCELLATION
Figure 3. Adjustments Accessible From the Underside

DIP Switches (SW2)
Table 1. SW2 Functions and Settings
SWITCH
NUMBER SWITCH FUNCTION
DEFAULT
SETTING
1 Headset audible key press
beep on/off
On: No beep
Off: Beep activated
Off
2 Mic Kill on/off (Enables/disables
another user station from killing
the microphone on this station)
On: Mic kill enabled
Off: Mic kill disabled
On
3 Channel 1 20-kHz call/send
On: Enable 20 kHz signalling
Off: Disable 20 kHz signalling
On
4 Channel 2 Program Interrupt
On: Program interrupted
during talk
Off: No program interrupt
Off
5 Channel 1 Program Interrupt
On: Program interrupted
during talk
Off: No program interrupt
Off
6 Left Earpiece Source
On: Both channels
Off: Channel 2 only
On
7 Right Earpiece Source
On: Both channels
Off: Channel 1 only
On
8 Channel 2 20-kHz call/send
On: Enable 20 kHz signalling
Off: Disable 20 kHz signalling
On
NOTE: The Program Interrupt feature individually controls the program
audio for each channel. When the Program Interrupt feature is
enabled, program audio is shut off on that channel when the
Talk
key is pressed. If the Program Kill feature is enabled for a chan-
nel, the Program Interrupt feature will have no effect on that
channel.
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Balanced/Unbalanced Switch (SW1)
Set this switch to the balanced (BAL) position to use the US-2000 with
Audiocom® intercom channels. Set the switch to the unbalanced
(UNBAL) position for use with a Clear-Com® intercom system. (The
factory default setting is the balanced position for use with Audiocom®.)
Table 2. Jumper Functions And Settings
JUMPER
NUMBER JUMPER FUNCTION
DEFAULT
SETTING
J7 Program 1 Local Listen
Both pins shorted: Program 1 audible in local
headset or speaker during CH1 listen
No pins shorted: Program audio not audible
No pins
shorted *
J8 Program 2 Local Listen
Both pins shorted: Program 2 audible in local
headset or speaker during CH2 listen
No pins shorted: Program audio not audible
No pins
shorted *
J16 Balanced/Unbalanced Headset Mic Select
Pins 1&2 shorted: Unbalanced
Pins 2&3 shorted: Balanced
Pins 1&2
shorted
J17 Clear-Com / Audiocom Mic Level Select
Pins 1&2 shorted: Clear-Com
Pins 2&3 shorted: Audiocom
Pins 2&3
shorted
J19 Channel 1 20-kHz Call Receive enable/disable:
Pins 1&2 shorted: Disabled
Pins 2&3 shorted: Enabled
Pins 2&3
shorted
J20 Channel 2 20-kHz Call Receive enable/disable:
Pins 1&2 shorted: Disabled
Pins 2&3 shorted: Enabled
Pins 2&3
shorted
J21 DC Call enable/disable: Makes the US-2000 compatible with
Clear-Com DC call signalling
Pins 1&2 shorted: Disabled
Pins 2&3 shorted: Enabled
Pins 1&2
shorted
J22 Multi-Channel Speaker enable/disable:
Pins 1&2 shorted: Disabled
Pins 2&3 shorted: Enabled
Pins 2&3
shorted
J23 Single Channel Speaker enable/disable:
Pins 1&2 shorted: Enabled
Pins 2&3 shorted: Disabled
Pins 2&3
shorted
J24 Multi-Channel Speaker Sidetone enable/disable:
Pins 1&2 shorted: Disabled
Pins 2&3 shorted: Enabled
Pins 1&2
shorted
* For no pins shorted, the jumper is placed on one pin only.
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Adjustments
The following adjustments are accessible either internally (refer to Figure
2) or from the underside of the US-2000, as shown in Figure 3.
Return Cancellation Adjustments (R187, R188)
Adjusted at the factory to cancel audio output that may be re-
flected from the line. There is a separate adjustment for each
channel. The Return Cancellation should only require adjust-
ment when the channel impedance or capacitance changes sig-
nificantly. To adjust one channel; connect powered speaker (set
for full volume), enable TEST SIGNAL on desired channel, and
adjust appropriate Return Cancellation to minimize signal volume
on the speaker.
Limiter Adjustment (R198)
Adjusted at the factory for 1 Vrms audio output to the line. If the
microphone input is higher than 4 mVrms, adjust the pre-amp
Limiter to reduce clipping of the audio output signal, if neces-
sary.
CONNECTOR PIN CONFIGURATIONS
Mono Headset Connector
Type: XLR-4M
Pin 1 Headset microphone low
Pin 2 Headset microphone high
Pin 3 Headphone high
Pin 4 Headphone low
Panel Microphone or Stereo Headset Connector
Type: NTRK-8F
Pin 1 Panel microphone low
Pin 2 Panel microphone high
Pin 3 12 VDC
Pin 4 Headset microphone high
Pin 5 Right headphone high
Pin 6 Right headphone low
Pin 7 Left headphone high
Pin 8 Left headphone low
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Program Inputs
Type: DB9F
Pin 1 Ground
Pin 2 Program 1 input low
Pin 3 Program 2 input low
Pin 4 NC
Pin 5 NC
Pin 6 Program 1 input high
Pin 7 Program 2 input high
Pin 8 NC
Pin 9 NC
P.A. Output
Type: 1/8-inch Stereo Phone Jack
Unbalanced Wiring (-000 Model)
Tip: PA output high
Ring: Not used
Sleeve: Common
Balanced Wiring (-001 Model)
Tip: PA output high
Ring: PA output low
Sleeve: Common
Speaker Outputs
(Connect to a powered speaker or the auxiliary input of an amplifier)
Type: RCA Phone Jack
Tip: Speaker output high
Sleeve: Common
14

Intercom Channel Connectors
Type: One XLR-3M and XLR-3F pair for each channel
Audiocom® Mode (Internal switch SW1 set to BAL position)
Pin 1 Common
Pin 2 Intercom audio low and +24 VDC input
Pin 3 Intercom audio high and +24 VDC input
Clear-Com Mode (Internal switch SW1 set to UNBAL position)
Pin 1 Common
Pin 2 +24 VDC input
Pin 3 Intercom audio high
Expansion Out
Type: 2.0 mm stereo jack
Tip: Talk output
Ring: Listen input
Sleeve: Common
External Power
Type: 2.0 mm jack
Internal pin: positive (+)
External shell: negative (-)
15

SPECIFICATIONS
GENERAL
Power Requirements:
Channel supplied: 24 VDC nominal (12 to 30 VDC), 65 to 150 mA
External supply: 12 to 15 VDC, 65 to 150 mA
Environmental Requirements:
Storage: -20ºC to 80ºC; 0% to 95% humidity, non-condensing
Operating: -15ºC to 60ºC; 0% to 95% humidity, non-condensing
Dimensions:
1.75" (44.5 mm) H x 8.25" (209.5 mm) W x 5.25" (133.4 mm) D
Weight:
1.3 pounds (0.59 kg)
INTERFACE REQUIREMENTS:
Headset:
50 to 200Wdynamic microphone
150 to 600Wheadphones
Panel Microphone:
5 kWElectret microphone (-57 dB)
Balanced Intercom Channel:
Output Level: 1 Vrms nominal
Input Impedance: 300W
Bridging Impedance: greater than 10,000W
Return Cancellation: -40 dB, 35 dB adjustable range
Call Signalling:
Send: 20 kHz ±100 Hz, 0.5 Vrms ±10%
Receive: 20 kHz ±800 Hz, 100 mVrms
Mic-Off Frequency:
Send: 24 kHz ±300 Hz, 0.5 Vrms ±10%
Detect: 24 kHz ±800 Hz, 100 mVrms
Noise Contribution: less than -70 dB
Common Mode Rejection Ratio: greater than 50 dB
16

Unbalanced Intercom Channel:
Output Level: 200 mVrms ±10%
Input Impedance: 150W
Bridging Impedance: greater than 10,000W
Return Cancellation: -40 dB, 35 dB adjustable range
Call Signalling:
Send: 11 ±3 VDC
Receive: 4 VDC minimum
PROGRAM INPUT
Voltage Gain Range:
25 ±3 dB
Output Level:
1.0 Vrms nominal, 2.3 Vrms maximum
Input Impedance:
Balanced: 75 kW
Unbalanced: 38 kW
Common Mode Rejection:
Greater than 50 dB
PA OUTPUT
Output Level:
235 mVrms nominal
HEADPHONE AMPLIFIER
Voltage Gain:
30 ±3 dB
Maximum Output:
250 mW ±10% into 150W, 65 mW±10% into 600W
Frequency Response:
200 Hz to 8 kHz +1/-3db
Audible Alert:
2 kHz, at the headset
17

Total Harmonic Distortion:
Less than 0.2% at 200 mW
Sidetone:
18 ±2 dB, adjustable
PANEL MICROPHONE AMPLIFIER:
Voltage Gain:
·Mic to CHN; 25±3 dB, before limiting
·Mic to Headphone; adjustable, 45 dB ±10% maximum, into 150W
·Mic to PA; 15 ±3 dB, 235 mVrms ±10%
Frequency Response:
200 Hz to 8 kHz +1/-3dB
Total Harmonic Distortion:
Less than 0.2% at CHN output
VOX Range:
-75 to -30 dB, -60 dB factory set
SPEAKER OUTPUT:
Output Level:
0 dB nominal (1.0 Vrms)
Output Impedance:
1000Wnominal
Frequency Response:
200 Hz to 15 kHz +1/-3dB
18

FACTORY SERVICE
All equipment returned for repair must be accompanied by
documentation stating your return address, telephone number and proof
of date of purchase, along with a description of the problem. In lieu of
this, you may obtain a Return Authorization form from our Customer
Service Department.
Customer Service Department
Telex Communications, Inc.
9600 Aldrich Avenue South
Minneapolis, Minnesota 55420 U.S.A.
Telephone: [phone]
(Collect calls not accepted)
Return equipment to:
Service Department
Telex Communications, Inc.
West 1st Street
Blue Earth, Minnesota 56013 U.S.A.
Warranty Repairs - If in warranty, no charge will be made for the repairs.
Equipment being returned for warranty repair must be sent prepaid and
will be returned prepaid.
Non-Warranty Repairs - Equipment that is not under warranty must be
sent prepaid to Telex. If requested, an estimate of repair costs will be
issued prior to service. Once your approval for repair, and repair of
equipment is completed, the equipment will be returned on a collect
basis. Collect charges may be avoided by sending a signed check for
payment in full along with your signed estimate approval form (the
estimate includes the shipping charge).
19