Studio Technologies IFB Plus 2005 - Manual (Page 39)

Model 2 User Guide Issue 8, December 2005
Studio Technologies, Inc. Page 39
Telephone Interface:
Operating Modes: telephone line or standard audio
signal, switch selectable
Definition of Telephone Line: intended for connec-
tion to standard loop start telephone lines
Definition of Standard Audio Signal: intended for
connection to balanced or unbalanced audio signals
(no DC loop current)
Impedance (Telephone Line Mode): 700 ohms,
DC off-hook resistance 200 ohms
Impedance (Standard Audio Mode): 700 ohms
Telephone Line Requirements (Telephone Line
Mode): 2-wire, loop start, 10 mA loop current
minimum
Interconnection: mates with standard USOC RJ11
jack using standard 6-position modular cable
Disconnect (Telephone Line Mode): manual using
front-panel switch or automatically after detection of
25 0 mSec, nominal, break in loop current
Interface Control (Telephone Line Mode): switch
on front panel allows manual off-hook and manual
hang-up functions
Receive Audio Level: –15 dBu, nominal
Receive Audio Adjustment Range: ±8 dB
Indicator Lights: 2, one yellow LED indicates opera-
tion in standard audio mode, one red LED indicates
loop current flowing through interface
Telephone Interface 2:
Operating Modes: telephone line or standard audio
signal, switch selectable
Impedance (Telephone Line Mode): 700 ohms,
DC off-hook resistance 200 ohms
Impedance (Standard Audio Mode): 700 ohms,
receive mode, 2200 ohms send mode
Telephone Line Requirements (Telephone Line
Mode): 2-wire, loop start, 10 mA loop current
minimum
Ringing Detection (Telephone Line Mode): 40
to 150 V RMS, 18-68 Hz, ringer equivalence 0.93
Number of Rings to Answer (Telephone Line
Mode): 1, or a fraction of one ring
Interconnection: mates with standard USOC RJ11
jack using standard 6-position modular cable
Disconnect (Telephone Line Mode): manual using
front-panel switch or automatically after detection of
250 mSec, nominal, break in loop current
Interface Control (Telephone Line Mode): switch
on front panel allows manual off hook and manual
hang-up functions
Audio Routing Control: switch on front panel allows
interface to receive audio, send channel 1 audio, or
send channel 2 audio
Receive Audio Level: –15 dBu, nominal
Receive Audio Adjustment Range: ±8 dB
Send Audio Level: –6 dBu, nominal
Indicator Lights: 2, one yellow LED indicates opera-
tion in standard audio mode, one red LED indicates
loop current flowing through interface
Access Station Interface:
Connector Type: 9-pin D-type, female
Application: provides power, audio, control inputs,
and status lamps outputs for up to four Model 22
Access Stations
Power: +18 Vdc, filtered and regulated, current
limited
Audio Inputs: one input per IFB channel,
unbalanced, capacitor coupled, 100 k ohm input
impedance, –10 dBu nominal audio level
Control Signals: 3, one per IFB channel, one for
monitor mute function, all lines active low
Status Lamp Outputs: one per IFB channel, 9.6 Vdc
channel inactive, 14.5 Vdc channel active, nominal,
current limited
Monitor Output:
Application: designed to drive loads of 8 ohms or
greater
Connector Type: ¼-inch 2-conductor phone jack
Output Power: 4 W RMS into 8 ohms, measured
@ 1 kHz, 1% THD+Noise
Internal Microphone:
Type: electret condenser
Frequency Response: 3 dB low frequency rolloff
@ 105 Hz
Interrupt Audio Compressor Circuits:
Number of Circuits: 2, one per IFB channel
Type: dual slope
Ratio in Compression Area: 4 to 1
Ratio in Limiting Area: infinity