Line Interface
Number of channels: 4 per card, Max of 4 option cards per MIU
DSP Channel usage: 4 DSP IP channels per card, regardless of whether the channel is routed to a different host
Signaling: Loop start or ground
DTMF: DTMF detection for DDOI routing
Bypass phone operation: Phone is switched out of circuit whenever FXO channel is in use
Line Impedance: CTR21, 600R, 900R or Japan – software selectable
Return loss: >18dB 300-400Hz
Protection: FCC pt 68 type B longitudinal surge, 1500V: FCC pt 68 type B metallic surge, 800V
Ring equivalency number: REN <0.2
Longitudinal balance: >60dB (200-1000Hz); 40dB (1000-4000Hz)
Common mode rejection ratio (CMRR): On hook >70dB 50-500Hz Vcm=60Vrms Off hook >40dB 50-500Hz Vcm=60Vrms
Common mode overload level (CMOL): On hook >300Vrms 50-60Hz Off hook >250Vrms 50-60Hz
Max trip/ring voltage: 300V (Correct operation not implied) Recommended max 120V
Max loop current: 90mA
Ringing voltage – detect: Typically 22V, min 26V, 17-68Hz
Ringing voltage – no detect: Typically 14V, max 18V, 1768Hz
THD: <1% at 0dBm, 1kHz
Crosstalk: <-85dB (inter-channel and inter-card)
Insertion Loss: 0dB
Nominal line TX level: -9dBm ± 1dB
Input level adjustment Via software: –9dB to +12dB in steps of 1.5dB
Output level adjustment Via software: –34.5dB to +12dB in steps of 1.5dB. Mute option
Freq response: 300Hz – 3200Hz ± 2dB ref to 1kHz (8kHz sampling)