PBL 385 70/1SO Speech Network, Standard, 45dB Maximum Tx. Gain at Load Resistance = 0Ohm|47.5dB Maximum Tx. Gain at Load Resistance = 400Ohm|50dB Maximum Tx. Gain at Load Resistance = 900Ohm to 2200Ohm, 20-SOP
PBL 385 73/1SOS Speech Network, Standard, 45dB Maximum Tx. Gain at Load Resistance = 0Ohm|47.5dB Maximum Tx. Gain at Load Resistance = 400Ohm|50dB Maximum Tx. Gain at Load Resistance = 900Ohm to 2200Ohm, 14-SOP