JK Audio Broadcast Host User manual

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JK Audio
800-JK-Audio [phone] www.jkaudio.com [email protected]
Broadcast Host is covered by a 2-year warranty to be free from
defective workmanship and materials. In the event that the
Broadcast Host needs repair, you must call us to get an
authorization, and then carefully pack and ship it to us. You will
pay for shipping to us and we will pay for return back to you, UPS
ground. No free repairs will be made if the defect was caused by
misuse, weather conditions, or other cause, except for defective
workmanship or materials. THERE ARE NO EXPRESS OR
IMPLIED WARRANTIES WHICH EXTEND BEYOND THE
WARRANTY HERE MADE.
Warranty
JK Audi
o
Broadcast Host
Desktop Digital Hybrid
User Guide

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Broadcast Host will allow you to send and receive audio over
analog telephone lines. While this may seem like a simple
task that any telephone can do, the challenge is getting the
best quality audio from such a limited audio path.
A digital hybrid connects audio signals to a standard analog
telephone line without the variations in quality found with
analog hybrids. The main function of a hybrid is to bring in
the callers voice from the phone line, as clear and clean as
possible. In the real world, when you send your voice down
the telephone line it has a tendency to bleed over into the
caller’s audio. The hybrid must adapt to the phone line in
order to properly separate transmit and receive audio. We
use a 16 bit DSP to continuously monitor the phone line and
audio signals to deliver excellent separation. Our dual-
convergence algorithm can achieve excellent trans-hybrid
loss, typically exceeding 50 dB, without any setup.
The Broadcast Host controls and connectors are clearly
marked and ready for operation. The feature diagram will
help you pinpoint any minor questions that you may have. If
this is your first exposure to a hybrid, we suggest that you
read the entire manual to allow you to take advantage of all
these features.
Before you pick up the phone... Please thumb through the
rest of this manual. You might find those deep technical
questions are covered on later pages.
What is a Digital Hybrid?
Ready to go?
Any Questions?
Introduction
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FCC Registration (cont)
Repair Instructions
Rights of the telephone company
f it is determined that your telephone equipment is malfunctioning,
the FCC requires that it not be used and that it be unplugged from
the modular outlet until the problem has been corrected. Repairs to
this telephone equipment can only be made by the manufacturer or
its authorized agents or by others who may be authorized by the
FCC. For repair procedures, follow the instructions outlined under
the warranty section of the manual
If telephone equipment is causing harm to the network, the telephone
company may temporarily discontinue your telephone service. If
possible, they'll notify you before they interrupt service. If advanced
notice isn't practical, you'll be notified as soon as possible. You'll be
given the opportunity to correct the problem, and you'll be informed
of your right to file a complaint with the FCC.
Your telephone company may make changes in its facilities,
equipment, operations or procedures that could affect the proper
functioning of your JK Audio product. If such changes are planned,
you'll be notified by your telephone company.
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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 communications. 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 JK Audio can void the
user's authority to operate the equipment.
FCC Part 15 Compliance
FCC Registration
Connection and use with the nationwide telephone network
Information for the telephone company
The FCC requires that you connect this telephone equipment to the
national telephone network through a USOC RJ-11C modular
telephone jack.
This equipment may not be used with Party Line Service or Coin
Telephone Lines.
This equipment is hearing aid compatible.
Upon request from your local telephone company, you are required to
provide the following information:
a) The "line" to which you will connect the telephone equipment
(that is, your telephone number), and
b) The telephone equipment's FCC registration number. This can
be found on the bottom of your telephone equipment, and,
c) the ringer equivalence number (REN) for this equipment.
The REN is used to determine the quantity of devices which will be
connected to the telephone line. Excessive RENs on the telephone
line may result in the devices not ringing in response to an incoming
call. In most, but not all areas, the sum of the RENs should not
exceed 5.0. To be certain of the number of devices that may be
connected to the line, as determined by the total RENs, contact the
local telephone company.
Your new JK Audio product has been registered with the Federal
Communications Commission (FCC). This product complies with the
standards in Part 68 of the FCC rules.
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Features

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Call Button - Press this button to answer or place a
telephone call (takes the line off-hook).
Drop Button - Press this button to drop (hang up) a call.
Headphones - The 3.5mm stereo headphone jack
contains a mix of both the send input audio and the caller
audio.
Line Jack - Connect to a standard, single line, analog
telephone line.
Send 1 Level - Adjusts the signal level that you are
sending down the telephone line, through the female
XLR input.
Send 2 Level - Adjusts the signal level that you are
sending down the telephone line, through the 3.5mm mini
jack input.
Caller Level - Adjusts the level of the signal coming in
from the telephone line, going out the output jacks.
Headphone Level - Adjusts the signal level coming from
the 3.5mm front panel headphone jack.
OH LED - Lit when you are on line with a call (Off-Hook).
Power LED - Lit when unit is plugged in and receiving
power.
Send LEDs - Displays the signal level going out to the
telephone line.
Receive LEDs - Displays the signal level coming from the
phone line, after the DSP.
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Features (cont)
Inputs:
Outputs:
Send 1:
Send 2:
Balanced:
Unbalanced:
Headphone:
Phone Line:
Aux Phone:
Isolation:
Ringer:
Frequency:
Response
Power:
Size:
Weight:
Balanced Female XLR, 1k ohm, -10 mV RMS
(-35 dBv nom)
Mic/Line pad switch = +4 dBv max
3.5mm mono,20k ohm, 250 mV RMS (-10
dBv nom)
Male XLR, 200 ohm, 500 mV RMS (+4 dBv
max)
3.5mm stereo, 50 ohm, 250 mV RMS (0 dBv
max), Left = send, Right = caller
3.5mm stereo, 8 ohms, 250 mW mixed send
and receive
RJ11C
RJ11C
1500 VAC
0.9B REN
telephone side 200 Hz - 3600 Hz
120-240 VAC power supply (included)
7" x 6" x 1.6" (18 x 15 x 4.2 cm)
2.2 pounds (1 kg)
Specifications
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Remote Control Jack (cont)
RJ45 Pinout:
Pin 1: Ground
Pin 2: Call / Drop Control
Pin 3: Ring / OH LED
Pin 4: DTMF Input
Pin 5:
Pin 6: Reserved
Pin 7: Reserved
Pin 8: Reserved
Pin 2 is your main control pin.
+4.3 VDC
Contact your JK Audio dealer for additional information. Guest Module remote
keypad not available for sale in Europe, Australia or New Zealand.
Momentarily connect pin 2 to pin 5 (power) through a 100 ohm
1/4 watt resistor to take Broadcast Host off-hook.
Momentarily connect pin 2 to pin 1 (ground) through a 100 ohm
1/4watt resistor to release the phone line.
Pin 3 contains a 4.3 VDC, 40 mA current limited output to drive a
signal LED. We suggest adding a 200 ohm 1/4w resistor in series
with an LED connected to ground.
Pin 5 supply output is current limited to 100 mA with a resettable
fuse for use with the Guest Module and pin 2 connections. Do not
attempt to power additional circuitry from this pin.
Operation (cont)
Phone Jack - Connect a single line analog telephone for
call setup / dialing, or producer call screening.
Caller Output - Male balanced XLR output contains only the
callers voice.
Mic / Line switch - Sets the front end sensitivity of the Send
1 XLR jack. Set to if you intend to plug a microphone
directly to the Send jack. Set to if you are connecting
to the line or auxiliary output of a mic mixer.
Auto-Answer - Press this switch to enable the Broadcast
Host to automatically answer an incoming call and then
disconnect after the caller hangs up. Auto answer will
occur on the first ring.
Send 1 Input - Female balanced XLR input for signals
going into the phone line. Mic or line level input.
Send 2 Input - 3.5mm mono mini jack input for signals
going into the phone line. Line level.
3.5mm Output - Stereo mini jack output contains send and
receive audio determined by the send 1 and send 2 levels
and the caller level controls. Left channel contains your
local send audio and right channel contains the caller's
audio from the telephone line.
Remote Control Jack - 8 pin modular jack for connection to
the JK Audio Guest Module 1 Remote Keypad or your
broadcast console switch contacts.
Power Jack - For connection to supplied 9VDC regulated
power supply only.
Mic
Line
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Features (cont)

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Connecting Cables
Auxiliary Telephone
Although each application will require a slightly different setup,
there are four cables that everyone can agree upon:
Phone Line - Connect the supplied RJ-11 phone line cable
between the jack marked "Line" and your wall jack. Be sure this
jack can support standard analog telephone operation.
Send Audio - Connect a microphone or mixing console output
XLR cable to the Send jack on the Broadcast Host. Be sure to
set the Broadcast Host mic/line switch to the proper position for
your application.
Caller Audio - Connect the Caller Out jack to an input on your
mixing console.
Power - Connect the supplied DC power supply to the back of
the Broadcast Host and then to an AC power outlet.
Your Broadcast Host is now ready to take calls. You may want to
connect an auxiliary telephone to the Broadcast Host for call
setup, or you can simply use the Auto-Answer feature to answer
incoming calls.
Broadcast Host will disconnect the auxiliary telephone when you
press the Call button. You can use an auxiliary telephone to
place or screen a call, and then you can place the call on hold.
When you are ready to take the call on Broadcast Host, simply
press the Call button. Your telephone will automatically release
the hold while you talk. If you need to take the call back on the
aux telephone, simply pick up the phone before the Broadcast
Host Drop button is pressed.
Operation
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Send Signal Level
Receive Signal Level
Auto-Answer
Remote Control Jack
The Send LEDs display the signal level as it goes out over the
phone line. The goal is to drive the phone line at high enough
levels to avoid phone line noise, but not so loud as to cause
excessive clipping. Adjust the send level control until you see
occasional flashes of the red -3dB peak Send LED. These
flashes should occur during loud speech bursts. If the red LED
stays lit for extended periods you can assume that much of
your speech is being clipped or distorted. In this case you
should back down on the Send volume control for the input that
is causing the clipping.
The receive LEDs display the signal coming from the phone
line and out of the DSP. The Caller level control does not
change what you see on these LEDs. Adjust the Caller level
control to give you the best signal at your equipment.
The Auto-Answer feature will answer on the first ring. When
Auto-Answer is enabled, you can still take calls manually using
the call button. When finished, you can either drop the call
manually or allow the call to Auto-Disconnect. Broadcast Host
will look for a CPC disconnect signal or ROH message from the
phone company to determine when a call has disconnected.
This can take up to a minute.
The RJ-45 jack on the back of the Broadcast Host provides
connection to a JK Audio Guest Module Remote Control, or to
the switch contacts on your broadcast console.
Operation (cont)