JK Audio Innkeeper PBX User manual

innkeeper PBX
Desktop Digital Hybrid
JK Audio
User Guide

2
Introduction
Innkeeper PBX will allow you to send and receive audio
through your multi-line PBX, ISDN or analog telephone. While
this may seem like a simple task that any telephone can do,
the challenge is getting the best quality audio from such a lim-
ited audio path.
What is a Digital Hybrid?
The innkeeper PBX digital hybrid connects audio signals to
and from the handset side of a telephone without the varia-
tions 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 audio signals from the telephone in order to properly sepa-
rate transmit and receive audio. We use a 16 bit DSP to con-
tinuously monitor the audio signals from the telephone to de-
liver excellent separation. Our dual-convergence algorithm
can achieve excellent trans-hybrid loss, also known as
"separation".
Ready to go?
The innkeeper PBX 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 fea-
tures.
Any Questions?
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.

3
Features
1 2 3 4 5 6 7
8 9
10 11
1. Handset Button - Press this button to use the handset as if you
were on a normal call.
2. Broadcast Button - Press this button to disable the handset and
activate the innkeeper PBX for use as a digital hybrid.
3. Send 1 Level - Adjusts the signal level that you are sending
down the telephone line, through the female XLR input.
4. Send 2 Level - Adjusts the signal level that you are sending
down the telephone line, through the 3.5mm mini jack input.
5. Caller Level - Adjusts the level of the signal coming in from the
telephone line, going out the output jacks.
6. Headphone Level - Adjusts the signal level coming from the
3.5mm front panel headphone jack.
7. Headphones - The 3.5mm stereo headphone jack contains a
mix of both the Send input audio and the Caller audio.
8. ON LED - Lit when you are on line with a call using the digital
hybrid within the innkeeper PBX.
9. Send LEDs - Displays the signal level going to the phone line.
10. Power LED - Lit when unit is plugged in and receiving power.
11. Caller LEDs - Displays the signal level coming from the phone
line, after the DSP.

4
Features (continued)
12 13 14 15 16 17 18 19 20
12. Handset Jack - Connect your telephone handset to this jack.
13. Phone Jack - Connect this jack to the handset jack on your tele-
phone using the supplied handset jumper cable.
14. Handset Type Selector Switch - Use this switch to select the
correct type of handset microphone that your telephone uses.
A=Electret, B=Carbon, C=Dynamic
15. Caller Output - Male balanced XLR output contains only the
caller’s voice.
16. Send 1 Input - Female balanced XLR input for signals going into
the phone line. Mic or line level input.
17. Mic / Line switch - Sets the front end sensitivity of the Send 1
XLR jack. Set to Mic if you intend to plug a microphone directly
to the Send jack. Set to Line if you are connecting to the output
of a mic mixer.
18. Send 2 Mono Input - 3.5mm mono mini jack input for signals
going into the phone line. Line level.
19. Stereo Output - 3.5 mm stereo mini jack output contains Send
and Caller 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.
20. Power Jack - For connection to supplied 9VDC regulated power
supply only.

5
Connection
Although each application may require a slightly different setup,
there are two primary configurations.
For a direct connection to innkeeper PBX:
• Handset cable - Connect the supplied RJ-22 handset cable be-
tween the jack marked "Phone" on the back of innkeeper PBX
and to the handset jack of your telephone.
• Handset - Connect your telephone handset to the RJ-22 jack on
the back of the innkeeper PBX marked "Handset".
• Send Audio - Connect a dynamic microphone cable to the Send
1 jack on the innkeeper PBX. Be sure to set the Mic/Line switch
to the “Mic” position.
• Output - Connect a stereo cable from the mini-jack Output on the
innkeeper PBX to the “Line In” on your computer sound card or
other recording equipment.
• Power - Connect the supplied DC power supply to the back of
the innkeeper PBX and then to an AC power outlet.
• Place a call to a quiet location. Set the “A-B-C” switch on inn-
keeper PBX for best audio.
• Set the “Send” level control so that while you are speaking into
the microphone, the Send LED’s on the hybrid light the -20 dB
green LED consistently and flash the -9 dB green LED. If you
flash the -3 dB red LED, lower the level. Set the “Caller” control
for good recording level of the caller audio.
Sound Card
Line
in Line out Mic in
Set to
“Mic”
Computer

6
Connection (continued)
To connect innkeeper PBX through a mixer—Mix Minus Setup
Number of microphones
depends on mixer
Caller to any
line level input Aux Send to Send 1,
Mic/Line button out (Line)
Use Main Outputs,
USB or Firewire
connectors to
send audio to
recording device,
or broadcasting
equipment inputs
For whichever input channel you have the Caller connected to, turn the
corresponding Aux control to minimum (usually hard left). All other Aux
controls should be set for what you want to send to the phone line. Each
Aux Send bus is completely separate from all other outputs, so these Aux
controls will not affect what is heard on the Main outputs or on any other
Aux buses. This Aux Send bus should be pre-fader, so you can use the
fader controls to set the levels of each channel to the main output.

7
• Make all cable connections
• On your mixer and on the innkeeper PBX, set all controls to nominal
levels, usually 12:00.
• On your mixer, set local microphone channel input sensitivity for mi-
crophone level.
• On your mixer, set the main mix control for good recording level of the
local audio.
• On your mixer, set the headphone level for comfortable listening.
• On your mixer, set the Caller channel input gain to line level, if appli-
cable.
• On your mixer, set the Caller channel Aux control to minimum (zero).
• Place a call to a quiet location. Set A-B-C switch on innkeeper PBX for
best audio.
• On your mixer, set the Aux Send control so that while you are speak-
ing into the microphone the Send LED’s on the hybrid light the -20 dB
green LED consistently and flash the -9 dB green LED. If you flash the
-3 dB red LED, lower the level.
• On your mixer, set the Caller channel output level for good recording
level of the caller audio. If you need more control of this level, on the
mixer first adjust the caller channel input gain (if applicable), then ad-
just Caller control on the innkeeper PBX.
• If you have a stereo mixer with no auxiliary output, you may pan your
local audio to the left, your caller audio to the right, and connect a left
channel output to the innkeeper PBX Send input.
• You may also use an external Mix-Minus box that will create this sig-
nal for you if your equipment is not capable.
Mix-Minus Setup
A mix-minus signal is an audio signal that contains a mix of your local
microphones plus any other audio, minus the Caller's own
voice. Sending the Caller’s audio back to the innkeeper PBX through
Send 1 will cause an echo, or feedback. If your mixer does not have an
Aux Send bus, you can achieve the same results using Pan controls
with the Left and Right outputs. Simply pan all the microphones, etc. to
the Left output and pan the Caller to the Right output. Then connect
only the Left output to the innkeeper PBX Send 1.
Operation

8
Operation (continued)
Telephone Handset
Innkeeper PBX will disable the telephone handset when you press the
Broadcast button. Use your telephone to place or screen a call. When you
are ready to take the call on innkeeper PBX, simply press the Broadcast
button. Make sure you do not put the telephone handset back in it's
cradle while you are on a call. This will still drop the call even though the
handset itself is disabled. If you need to take the call back on your tele-
phone, simply press the Handset button on innkeeper PBX. This will dis-
able the inputs and outputs on innkeeper PBX and connect your handset
back to the telephone.
Send Signal Level
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 so that you rarely see flashes of the red -3dB peak Send LED.
These flashes should occur only 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.
Caller Signal Level
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 for the best signal at your equipment.
ABC Selector Switch
Use this switch to select the correct type of handset microphone your tele-
phone uses. A=Electret, B=Carbon, C=Dynamic. Trial and error seems to
work best in determining which handset type to use. Your innkeeper PBX
will only function correctly if the handset type selector switch is in the cor-
rect position. This switch changes signal level, impedance, and wiring to
accommodate the differences in handset microphone types. To determine
the correct position, you must place a call to another telephone line, then try
to send audio into the innkeeper PBX through the inputs. While doing this,
switch between the three different handset type positions. Choose the posi-
tion that works best by monitoring the audio quality and send LED's.
Although not conclusive, the following guidelines may help:
The majority of newer telephones have electret type microphones and will
use the "A" position.
Older telephones that have the round "screw type" handsets contain carbon
microphones and use the "B" position.
Many Radio Shack®, Panasonic®, and Nortel®telephones have dynamic
microphone types and use the "C" position.

9
FAQ’s
?Will innkeeper PBX work with my ___ PBX phone system?
!Probably yes. We have to say probably because the handset interface is
proprietary and therefore can change from model to model. We have no
way of predicting how a phone manufacturer will use the handset wires in
the future. The three handset microphone types that we support, electret,
dynamic, and carbon, cover every handset microphone type that we have
seen in use, but the wire diagrams can change without notice.
?Will your digital hybrid provide phantom power for a condenser mic?
!No, this device will not provide phantom power. If you are connecting your
microphone directly to the innkeeper PBX, use a dynamic mic.
?Why is there a Send 2 mini-jack on the back of my innkeeper PBX?
!This is a second line level input to innkeeper PBX. This is where you can
connect another device, such as a CD player, the Line Out from your Com-
puter or even the output of your personal audio player, to add audio to the
conversation. This enables you to play background music or other sound
bites during your discussion. Do not connect a microphone to this jack.
This is a mono jack. If connecting a stereo output such as a computer Line
Out, you will receive only Left channel audio on this jack.
?How do I record onto my computer and edit the files?
!You will need to purchase or download any audio editing software of your
choice. You may also need to edit the audio configuration files on your
computer or in your software to allow recording in stereo. Innkeeper PBX
just allows you to access the audio from your phone line.
?Does innkeeper PBX come with any Talk Show software?
!No, our description "Turn your PBX into a low cost talk show system" per-
tains to using a multi-line PBX phone system as a line selector switch.
When the innkeeper PBX is on line, simply select which phone line you
want to talk to, either dropping the last caller, or putting them back on hold.
?Why can't I dial out on my phone and I hear a lot of noise on the call?
!The innkeeper PBX will not work with any telephone that has a keypad in
the handset. You need to use a telephone with a standard handset.
?I have everything connected correctly. Why can't the caller hear me?
!You cannot use the speakerphone function on your telephone during your
recording. Innkeeper PBX accesses the audio through the handset cord.
With the speakerphone turned on, there is no audio going through the
handset. You need to use a microphone through the innkeeper PBX.
?When I record from the Output on my innkeeper PBX, I am only get-
ting my own voice on the recording.
!While there are two mini-jacks together on the back of innkeeper PBX,
only one is an Output. The jack marked “Send 2” is a second input. The
jack on the right is a stereo Output, with the Send audio on the left chan-
nel and the Caller audio on the right channel of the same stereo cable.

10
FCC Part 15 Compliance
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.
Inputs:
Send 1: Balanced Female XLR, 1k ohm, -10 mV RMS
(-35 dBv nom)
Mic/Line pad switch = +4 dBv max
Send 2: 3.5mm mono,20k ohm, 250 mV RMS (-10 dBv nom)
Outputs:
Balanced: Male XLR, 200 ohm, 500 mV RMS (+4 dBv max)
Unbalanced: 3.5mm stereo, 50 ohm, 250 mV RMS (0 dBv max),
Left = send, Right = caller
Headphone: 3.5mm stereo, 8 ohms, 250 mW
mixed send and receive
Aux Phone: RJ11C
Phone Line: RJ11C
Isolation: 1500 VAC
Ringer: 0.5B REN
Frequency Response: Telephone side 200 Hz - 3600 Hz
Power: 120-240 VAC power supply (included)
Size: 7" x 6" x 1.6" (18 x 15 x 4.2 cm)
Weight: 2.2 pounds (1 kg)
Specifications
FAQ’s (continued)
?Can innkeeper PBX auto-answer or auto-disconnect?
!No, the handset cord on your telephone is only active when the handset
is off-hook. This is done manually. There is no way to then auto-
disconnect. You must return the handset to the cradle.
?There is a loud hum on the output of my innkeeper PBX, even
when nothing else is connected. What else could it be?
!Make certain you are using the regulated power supply that was
shipped with the unit. Power supplies are not all the same.