Details Momentary/Latching Talk switch with LED Microprocessor controlled logic and switching Visual call signaling Headset connector with volume control and sidetone adjust Optional 4-wire daughter board for flexibility Mountable into a standard US two-gang outlet box Item Code HB-702 Technical Specifications Headset Microphone Input Input Type: Dynamic Input Impedance: >= 1K Mic Limiter Threshold: -2dBu ± 3dB Mic Limiter Range: >= 15dB Program Line Input Input Impedance: >= 5K Headset Output Load Impedance: >= 8 Output Impedance: <= 25 Output Limiter Threshold: +5dBu ± 3dB Maximum Output Level before Distortion: >= 17dBu Partyline Output Off Noise: < -74dBu Output Impedance: >10K Partyline Input Crosstalk: < -60dB Max level before Clipping: >= 12dBu Frequency Response Headset Mic - Partyline: 300 - 15kHz ± 3dB Partyline - Headset Out: 300 - 15kHz ± 3dB Max Distortion Headset Mic - Partyline: <= 0.5% Partyline - Headset Out: <= 0.2% Noise Headset Mic - Partyline: < -70dBu Max Gain Headset Mic - Partyline: 41dB ± 2dB Partyline - Headset Out: >= 34dB Power Input Voltage Range: 20-30V DC Input Current (Idle): <= 50mA Input Current (Max): <=100mA Internal Adjustments and Connections Intercom Line: Seven terminal connector Option Switches: Two DIP switches Option Board Jumper: Two sets of options jumpers Environmental 32 - 122°F (0 - 50°C) Dimensions 4.5 x 4.6 1.75in (HxWxD) (114 x 117 x 44mm) Weight 0.46lbs (0.21kg)