JK Audio Four IFB User Manual

Four IFB

Multi Line Phone Bridge

User Guide

JK Audio

Important Safety Instructions

1. Read these instructions.

2. Keep these instructions.

3. Heed all warnings.

4. Follow all instructions.

5. Do not expose this unit directly to water. Although this unit is
designed to be as moisture repellent as possible, it is not in­tended to be used unprotected in the rain, under water, etc. This
unit is neither 100% water proof nor water tight. When used in a
wet or damp environment, battery power is recommended.

6. Do not place liquid filled containers on the unit such as water
glasses, coffee cups, etc.

7. Clean only with dry cloth.

8. Install in accordance with manufacturer's instructions.

9. Do not install near heat sources such as radiators, heat regis­ters, stoves or other devices that produce excessive heat.

10. Do not defeat the safety purpose of the grounding-type plug.
The grounding prong is provided for your safety. If the provided
plug does not fit in your outlet, consult an electrician for replace­ment of the obsolete outlet.

11. Use only the 3 prong grounded AC cable provided with the unit
when connecting to AC power.

12. Use of a surge suppressor for AC power and phone lines is rec­ommended.

13. Unplug this unit during lightning storms or when unused for long
periods of time.

14. Protect the power cord from damage at all times. Special atten­tion should be paid to the location where the cable connects to
the unit and to the AC outlet.

15. Refer all servicing to qualified personnel.

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Introduction

Four IFB is a four position analog telephone line interface de­signed specifically to provide flexible listen only IFB* for television
field production use. In addition to the four line- level balanced
XLR outputs, the unit is equipped with one balanced XLR line level
monitor input and one balanced XLR monitor output. Each IFB
output, and the monitor input / output jacks, may be separately
connected to one of the four analog phone lines through the use of
rotary line selector switches. A telephone handset may also be
connected for use with the monitor line selector switch. Level of
each of the six XLR jacks is adjustable individually with independ­ent volume controls.

Individual on-hook/off-hook function for each phone line is con­trolled by the Monitor Add and Drop switches. The phone line to
be controlled with these switches is determined by the Monitor ro­tary line selector switch. On-hook / off-hook relay condition will be
maintained regardless of whether an active POTS line is physically
connected to the unit, or if the unit is in a powered "on" state or
not. Temporary power loss will not disconnect an active phone
line.

The position of the monitor rotary line selector switch determines
which line is added or dropped. Calls may be placed directly from
the unit with the integrated DTMF keypad. No external dialer is
needed.

Four IFB is designed to be used in a variety of environments and
weather conditions. Although the unit is not "waterproof", all con­trols and components are dust and moisture resistant. A non­removable hinged cover protects the unit's selector switches, add/
drop buttons and keypad while the enclosure design protects the
volume controls from physical damage. When used in a wet or
damp environment, battery power is recommended.

*IFB is a broadcast industry acronym which stands for Interruptible
Fold Back. The IFB signal is typically a Program Line (PL) signal
from the studio console.

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Quick Setup Guide

1. Connect AC power to the
unit with the provided AC
cable. The AC power
LED should light green.

2. Connect up to four ana­log (POTS) telephone
lines to the RJ-11 jacks.

3. Connect a handset to the
monitor handset jack and/or
connect the Monitor Send and
Receive XLR jacks to your
audio equipment for commu­nication.

4. Connect the IFB XLR
output(s) to your audio
equipment for distribution
of IFB audio feeds.

NOTE: You cannot connect a

mic directly to the Monitor
Send SLR. This is a line level
input.

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Quick Setup Guide

5. Turn on the Power switch.
The power LED should
light red.

6. Rotate the Monitor selector
switch to the desired Line
position. Line 1 = phone
line connected to RJ-11
marked Line 1.

7. Press the Add button.
This will take the selected
line off-hook. The
corresponding Line LED
will light green.

8. Dial the call with the DTMF keypad.

You may now communicate with the called party on Line

1 through the Monitor handset or equipment connected to
the Monitor Send and Receive SLR jacks (optional).

Repeat steps 6-8 for Lines 2-4.

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Quick Setup Guide (continued)

9. Use the IFB 1-4 rotary
switches to select which
phone line audio will be
sent to the corresponding
IFB XLR output jack.

Example: Setting IFB 1
rotary switch to “Line 4”
will send audio from
phone line 4 to the IFB
XLR output 1.

10. Adjust audio levels as needed using corresponding volume
controls.

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