RTS BP-325 User manual

9350-5690-00 Rev. M 8/2008
II
I
MODEL BP-325
Belt-pack Intercom Station
User Manual

PROPRIETARY NOTICE
The product information and design disclosed herein were originated by
and are the property of Telex Communications, Inc. Telex reserves all
patent, proprietary design, manufacturing, reproduction, use and sales
rights thereto, and to any article disclosed therein, except to the extent
rights are expressly granted to others.
COPYRIGHT NOTICE
Copyright 2007 by Telex Communications, Inc. All rights reserved.
Reproduction, in whole or in part, without prior written permission from
Telex is prohibited.
WARRANTY NOTICE
See the enclosed warranty card for further details.
CUSTOMER SUPPORT
Technical questions should be directed to:
Customer Service Department
RTS/Telex Communications, Inc.
12000 Portland Avenue South
Burnsville, MN 55337 USA
Telephone: [phone]
Fax: [phone]
Factory Service: 800-553-5992
RETURN SHIPPING INSTRUCTIONS
Customer Service Department
Telex Communications, Inc. (Lincoln, NE)
Telephone: [phone]
Fax: [phone]
Factory Service: 800-553-5992
Please include a note in the box which supplies the company name,
address, phone number, a person to contact regarding the repair, the type
and quantity of equipment, a description of the problem and the serial
number(s).
SHIPPING TO THE MANUFACTURER
All shipments of product should be made via UPS Ground, prepaid (you
may request from Factory Service a different shipment method). Any
shipment upgrades will be paid by the customer. The equipment should
be shipped in the original packing carton. If the original carton is not
available, use any suitable container that is rigid and of adequate size. If
a substitute container is used, the equipment should be wrapped in paper
and surrounded with at least four (4) inches of excelsior or similar
shock-absorbing material. All shipments must be sent to the following
address and must include the Proof of Purchase for warranty repair.
Upon completion of any repair the equipment will be returned via
United Parcel Service or specified shipper, collect.
Factory Service Department
Telex Communications, Inc.
8601 East Cornhusker Hwy.
Lincoln, NE 68507 U.S.A.
Attn: Service
This package should include the following:
Qty Description Part No.
1 Final Assy, BP325, Gray 9010673800
Final Assy, BP325, Rev
2.0 9010673820
Final Assy, BP325, Black 9010673821
1 User Manual 9350569000
1 Warranty Statement 38110387
1 EMC & LVD Statement 38109675

Table
Of
Contents
Chapter 1 - Connections And Operation
Connections .................................................................................................................................................1
Headset ........................................................................................................................................................1
Intercom Channels ......................................................................................................................................1
Operation ....................................................................................................................................................2
Programmable Options ...............................................................................................................................3
Factory Settings ..........................................................................................................................................3
Jumpers (W1-w7) ........................................................................................................................................4
Sidetone Adjustment ....................................................................................................................................5
Alternate Powering Methods ......................................................................................................................5
General ........................................................................................................................................................5
Method One: One Channel Operation With A Non-rts Power Supply .......................................................5
Line Input Connector Wiring For 1-channel Operation With Non-rts Power Supply ................................6
Bottom View Of The Main Circuit Board ...................................................................................................6
Line Loop Connector Wiring For 2-channel Operation With Non-rts Power Supply. ...............................6
Line Input Connector Wiring For 2-channel Operation With Non-rts Power Supply ................................6
Method Two: Two Channel Operation With A Non-rts Power Supply .......................................................7
Chapter 2 - Replacement Parts
Where To Obtain Parts ...............................................................................................................................9
Electrical Parts .........................................................................................................................................10
Chapter 3 - Specifications And Drawings
Specifications ............................................................................................................................................15
Drawings ...................................................................................................................................................16
Front Panel Board Assembly, Bp325 ........................................................................................................17
Main Board, Bp325 ...................................................................................................................................18
Rear Panel Assembly, Bp325 ....................................................................................................................19
Rear Panel Assembly, Bp325 ....................................................................................................................20
Final Assembly, Bp325 .............................................................................................................................21
Schematic Diagram, Front Panelcircuit Board ........................................................................................22
Schematic, Main Board Page 1 .................................................................................................................23
Schematic, Main Circuit Board Page 2 ....................................................................................................24
Bp-325 Cable Assemblies ..........................................................................................................................25

1
CHAPTER 1
CONNECTIONS AND OPERATION
This section describes operation of the BP325 as supplied from the factory. Use of an RTS power supply to power the intercom
system is assumed. For options and use of an alternate power source (See “PROGRAMMABLE OPTIONS” on page 3. and
See “ALTERNATE POWERING METHODS” on page 5..
CONNECTIONS
Headset
Connect a headset using one of the three headset connectors on the back panel. The MONO HEADSET and STEREO
HEADSET connectors are for monaural or stereo dynamic-mic headsets. The CARB-MIC HEADSET connector is for a
monaural carbon-mic headset. Refer to the specifications for pin-outs of these connectors if needed.
Intercom Channels
Connect the BP325 to the intercom system using the LINE INPUT connector on the back panel.
If desired, connect an additional intercom station to the intercom system using the LINE LOOP connector on the back panel.

CONNECTIONS AND OPERATION
2
OPERATION
1. Attach the BP325 to your belt or other convenient location using the belt clip on the rear panel.
2. Put on the headset and adjust the listen volume controls while listening to the intercom channels.
3. A TALK button may be activated in either of two ways:
Momentary Mode: Press and hold the TALK button, then speak into the microphone. The green talk
LED will remain lit while the TALK button is held. Release the TALK button when finished talking.
The talk LED will turn off.
Latching Mode for Hands-free Conversation: Tap the TALK button (do not press and hold). The
green talk LED will turn on and remain on. When finished talking, tap the TALK button again. The
talk LED will turn off.
4. Calling an intercom channel:
a.Turn on the TALK button for the channel to be called (the green talk LED should be lit).
b.Press and hold the CALL button. The red call LED will light while the button is pressed, indicating
that a call signal is being sent. When a response is heard, release the CALL button and begin your
conversation.
c.Turn off the TALK button when finished with your conversation.
5. Receiving a call:
TAL KTAL K
C A L L
RTS SYSTEMS
BP325 PORTABLE HEADSET STATION
MONO
HEADSET
LINE LOOP
AUX I/O
CARB-MIC
HEADSET
LINE
INPUT
PGM
VOL
STEREO
HEADSET
REMOVE
COVER
4 5
1 2
3
6 7 10b 8 9
10a
10a
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Channel 1 talk button, indicator light and listen
volume control.
Channel 2 talk button, indicator light and listen
volume control.
Call button and indicator light.
Carbon-mic headset jack. May also be used
for external mic switch. See "Programable Options".
Program volume control. Active only when using the
line loop connector for optional program input.
See "Programable Options".
Monaural dynamic-mic headset jack.
Intercom line loop connector for connection to
additional intercom stations. May also be used for
external program input, external mic switch, or a
non-standard power source. See "Programable Options"
and "Alternate Powering Methods".
Intercom line connector. For connection to intercom
system.
Stereo dynamic-mic headset jack.
Rear cover removal to set options:
Loosen two screws (10a) and remove
one screw (10b).

3
FACTORY SETTINGS
a.When there is an incoming call on a channel, the red call LED will flash.
b.If a talk LED is also flashing, this indicates that you need to activate that TALK button to begin
your conversation.
c.If no talk LED is flashing, this indicates that the TALK button is already on; simply begin your con-
versation.
6. Sending a Talk-off Signal: The BP325 can generate an inaudible signal which can be used to deactivate the talk buttons on
other intercom stations connected to an intercom channel. (May be used with models BP325, MCE325 and MRT327). This
feature is useful when an unattended intercom station has its microphone activated and is causing noise on an intercom
channel. To send a talk-off signal:
a.Turn off both TALK buttons on the BP325.
b.Tap the CALL button three quick taps. The red call LED will turn on for about 2 seconds.
c.While the red call LED is on, momentarily press the TALK button for the channel that has the
TALK button to be turned off. This will send the signal and turn off the remote TALK button.
PROGRAMMABLE OPTIONS
Several internal option switches and jumpers can modify the belt pack’s operation. The factory settings are summarized
below. To change any of the factory settings, remove the rear cover screws as shown in Figure 1. Jumper and switch locations
are shown on the label inside the rear cover.
FACTORY SETTINGS
TABLE 1. BP-325 Unit Jumper Settings - This equipment complies with the requirements in Part 15 of the FCC Rules for a
Class A computing device. Operation of this equipment in a residential area may cause unacceptable interference to radio
and TV reception requiring the operator to take whatever steps are necessary to correct the interference.
TRS JACK FUNCTION
EXT
MIC
SW
CARB
MIC
HOST
W7
SW 1 CALL SIGNAL DISABLE
SW 2 MOMENTARY ONLY CH 2
SW 3 TALK 2 DISABLE
SW 4 TALK 1 DISABLE
SW 5 MOMENTARY ONLY CH 1
SW 6 TALK OFF TRANSMIT ENABLE
SW 7 NOT USED
SW 8 TALK OFF RECEIVE ENABLE
12345678
ON
S1
W1
THRU
W4
ON
W4
W3
W2
W1
W5
W5
PGM RIGHT
PGM LEFT
CH 2 LISTEN
CH 1 LISTEN
MONO
STEREO
BAL2
R52
BAL1
R39
MONO 4-PIN
HEADSET
STEREO 5-PIN
HEADSET
INTERCOM
INPUT
INTERCOM
LOOP
PGM INPUT
REMOTE MIC SW/
LOCAL POWER
J2
J3
J7
J6
J4
J5
1
1
1
1
1

CONNECTIONS AND OPERATION
4
Jumpers (W1-W7)
No.
Setting Description Factory Default
W1 CH 1 Intercom Audio Listena
a. Listen is factory set to be ON all the time on both
channels. Setting W1 to the OFF position will dis-
able intercom listen audio on channel 1 (usually
the left headphone of a stereo headset). Setting W2
to the OFF position will disable intercom listen
audio on channel 2 (usually the right headphone of
a stereo headset). Listen disable could be used, for
example, when you want to use the left side of a
stereo headphone exclusively for program audio
input and the right side for a single channel of
intercom audio. In this case you would:
1. Set W1 to OFF to disable channel 1 intercom
audio listen to the left headphone.
2. Set DIP switch 4 to ON to disable channel 1
talk.
3. Setup the left channel for program input.
ON
W2 CH 2 Intercom Audio ListenaON
W3 Program input to left headphonebOFF
W4 Program input to right
headphonebOFF
W5 Stereo/Mono operationcStereo
W6 Not Used
W7 CARB/MIC Jack FunctiondHeadset
DIP Switches (S1)
1 Call Signal Transmit Disable OFF
2Momentary Only Talk Button,
CH2eOFF
3CH2 Talk DisablefOFF
4CH1 Talk DisablefOFF
5Momentary Only Talk Button,
CH1eOFF
6Talk-off Transmit enablegON
7NotUsed OFF
8Talk-off Receive Enableh
iON
b. To use program audio input:
1. Unplug the LINE LOOP connector from J6, and
plug it into J5.
2. If you are using a stereo headset, set W3 and/or
W4 to ON to route the program audio to the left
headphone, right headphone or both headphones.
If you are using a mono headset, set both W3 and
W4 to ON.
3. Connect the program source to the LINE LOOP
connector using an XLR-3-32 female receptacle
wired as follows
Pin 1 - Common
Pin 2 - Program input high
Pin 3 - Program input low
4. Adjust program input volume using the PGM
VOL control on the back panel.
c. W5 applies to a stereo dynamic-mic headset con-
nected to the STEREO HEADSET jack. With W5
set in the stereo position, intercom channel 1 will
be heard in the left headphone only, and channel 2
will be heard only in the right. In the mono posi-
tion, both intercom channels (andprogram audio if
connected) will be heard in both headphones. If
you are using monaural headphones connected to
the MONO HEADSET jack, W5 may be left in the
stereo position.
d. The CARB-MIC connector may be used to con-
nect either a headset or an external mic ON/OFF
switch. (If you are using a carbon-mic headset, but
still wish to use an external mic switch, the LINE
LOOP connector may alternatively be used for the
mic switch. See note X, below.) To use the CARB-
MIC connector for an external mic ON/OFF
switch:
1. Place jumper W7 in the “EXT MIC SW” posi-
tion.
2. Use a stereo phone plug to connect the external
switch to the CARB-MIC HEADSET jack:
Tip: Remote Mic Switch Normal-open
Contact
Ring: No connection
Sleeve: Remote Mic Switch Common
3. To use the external mic switch, first set one or
both TALK buttons to the latched-on position.
Then, press the external mic switched turn the
TALK button(s) ON. Release the mic switch to
turn the TALK button(s) OFF. Note, the TALK
buttons may still be turned ON or OFF from the
BP-325; however, the external mic switch will not
work unless the TALK buttons are first turned ON
at the BP-325

CONNECTIONS AND OPERATION
5
SIDETONE ADJUSTMENT
You can change the level of your own voice heard in your
headphones while talking on an intercom channel. Adjust
R39 to change your voice level when talking on channel 1.
Adjust R52 to change your voice level when talking on
channel 2.
ALTERNATE POWERING
METHODS
GENERAL
When using an RTS power supply to power the intercom
system, power is carried to the BP325 on pin 2 of the LINE
INPUT connector along with the channel 1 audio. Pin 1 is
the DC return. The unique design of RTS power supplies
permits power to be carried on an audio channel. RTS power
supplies also provide the proper terminating impedance for
each intercom channel. If a non-RTS power supply is used,
there are two alternatives for connecting power and intercom
audio.
The first method uses channel 1 only to connect the non-RTS
power supply. Audio on channel 1 will be unusable as the
power supply will look like a short circuit at audio
frequencies. Channel 2, however, will still be operational.
Also, channel 2 will require a terminating impedance, since
this is not supplied by the non-RTS power supply.
The second method allows the use of a non-RTS power
supply while still maintaining two audio channels. This
method requires an additional wire to the belt pack, and the
LINE LOOP connector will not be usable for connecting
another intercom station. Also, each intercom channel must
be properly terminated. The two methods are discussed
below.
METHOD ONE: ONE CHANNEL OPERATION
WITH A NON-RTS POWER SUPPLY
Using an XLR-3-32 female connector, connect the external
power source and the channel terminating components to the
LINE INPUT connector as
shown in Figure 2.
If desired, the LINE LOOP connector may be
used to connect power and audio to an additional
intercom station.
e. As supplied, the TALK buttons feature a dual-
action momentary/latching operation: press and
hold for momentary talk, then release when fin-
ished; or tap to latch ON for hands-free talk, and
tap again to turn OFF when finished talking. If
desired, the latching operation may be defeated,
and the TALK buttons may be operated in momen-
tary mode only.
f. Setting DIP switch 3 to the ON position will dis-
able the channel 2 TALK button. Setting DIP
switch 4 to the ON position will disable the chan-
nel 1 TALK button.
g. As supplied, the BP-325 can generate an inaudible
talk-off signal which can be used to deactivate the
talk buttons on other intercom stations connected
to an intercom channel. To turn this feature OFF,
set DIP switch 6 to the OFF position.
h. As supplied, other intercom stations candeactivate
the TALK buttons on the BP-325 using the Talk-
Off feature from their intercom stations. To disable
this feature, set DIP switch 8 in the OFF position.
i. Using the LINE LOOP connector for an external
mic ON/OFF switch:
1. Unplug the LINE LOOP connector from J6 on
the circuit board, and plug it into J4.
2. Connect the external mic switch to the LINE
LOOP connector using an SLR-3-32 female recep-
tacle wired as follows:
Pin 1: Remote Mic Switch Common
Pin 2: No Connection
Pin 3: Remote Mic Switch
Normal-open Contact
3. To use the external mic switch, first set one or
both TALK buttons to the latched-ON position.
Then, press the external mic switch to turn ON the
TALK button(s). Release the mic switch to turn off
the TALK button(s). Note, the TALK buttons may
still be turned ON or OFF from the BP-325; how-
ever, the external mic switch will not work unless
the TALK buttons are first turned on at the BP-
325.

CONNECTIONS AND OPERATION
6
FIGURE 1. LINE INPUT Connector Wiring for 1-Channel
Operation with Non-RTS Power Supply
FIGURE 2. Bottom View of the Main Circuit Board
FIGURE 3. LINE LOOP Connector Wiring for 2-Channel
Operation with Non-RTS Power Supply.
200 Ohms
+
Pin 1, Common
10mF /50V
Pin3,Ch2+Audio
Pin 2, +18 TO +24 VDC
TO BP325
LINE INPUT TO INTERCOM
CHANNELS AND
POWER SUPPLY
CUT
TRACE
Pin 1
Pin 2
Pin 3
+18to+24VDC
Common
No Connection
FIGURE 4. LINE INPUT Connector Wiring for 2-Channel Operation with Non-RTS Power Supply
200 Ohms
+
Pin 1, Common
200 Ohms
+
10mF /50V 10mF /50V
Pin3,Ch2+Audio
Pin2,Ch1+Audio
TO BP325
LINE INPUT TO INTERCOM
CHANNELS
OPTIONAL CONNECTOR
TO ADDITIONAL
INTERCOM STATION
LINE INPUT