JK Audio Inline Patch - Manual (Page 6)

6
Operation (continued)
The hybrid circuitry in the Inline Patch can provide a nominal
20 dB of transmit / receive isolation. When using the stereo
jack with stereo speakers, the 20 dB isolation will give you
substantial left / right separation. The separation on FM ste-
reo is typically around 20 dB.
Send Side (To Phone Line)
The Inline Patch includes a balanced female XLR jack and a
3.5mm (1/8”) mono mini jack to send audio to the telephone
line. These jacks can be connected to an audio output such
as the headphone output jack on a tape recorder, or the line
output of a PC audio card, CD player or audio mixer.
If you want to use a microphone to add extra audio to the
call, you will first need to add an amplifier to your microphone
so that the signal is boosted to line level. You can use both
the XLR and the mini jack input at the same time, and add it
to the audio coming from the handset microphone. The level
of the audio you send through the input jacks into the phone
line can be adjusted with the Send control. Note that this au-
dio will come back mixed with the caller audio, so be sure not
to overpower the caller’s voice with your own audio.
Off Hook - Norm Switch
This switch allows you to seize the phone line without using a
telephone. The switch should be set to “Norm” to dial out us-
ing a telephone. Set the switch to “Off-Hook” to seize the line
and answer an incoming call without using a telephone. This
switch can be remotely operated using your own switch con-
tacts connected to the N.O. Contacts jack on the back of the
unit. Simply wire a 3.5 mm plug to a normally open switch. A
short across tip and ring on a stereo plug will take the phone
line off-hook. You can also use a 3.5 mm mono plug.
Note: Seizing the phone line activates the internal circuitry of
the Inline Patch, essentially “turning it on”. The green LED on
the front panel only indicates that the unit is receiving power.
7
Specifications
Inputs (to phone line):
Balanced Connector
Female XLR
Input Impedance 1 k ohms
Level 250 mV RMS (-10 dBm nom.)
Line Connector
1/8” (3.5mm) mono mini jack
Input Impedance 20 k ohms
Level 250 mV RMS (-10 dBm nom)
Outputs:
Balanced Connector
Male XLR
Output Impedance 50 ohms
Level 500 mV RMS (+12 dBm max.)
Stereo Connector
1/8” (3.5mm) stereo mini jack
Output Impedance 50 ohms
Level 250 mV RMS (+12 dBm max.)
Mono Connector
1/8” (3.5mm) stereo mini jack
Output Impedance 50 ohms
Level 250 mV RMS (+12 dBm max.)
Remote:
Connector
1/8” (3.5mm) TRS stereo jack
Connect tip to ring to go Off-hook
Phone line:
Connector RJ11C
Isolation 1500 volts
Phone:
Connector RJ11C
Voltage
32 VDC