Applications
VOCORD A8 USB is used in multi-channel audio registration systems for recording signals from analog phone lines, microphones and other line outputs.
Description
VOCORD A8 USB is an autonomous device which is connected with control computer via USB cable. This product features high quality line interface. At sample frequency of 8 kHz the signal/noise ratio amounts to 78 dB. Hardware audio compression considerably decreases central processor loading and allows to create multifunction and trusted audio-recording systems.
Using VOCORD A8 USB and the pertaining equipment produced by Vocord Telecom company one can obtain a fax demodulator and fax projection decoder supporting the following fax protocols: Fax SuperG3, Т.30, Т.4, Т.6, V.21, V.8bis, V.27ter, V.29, V17, V34 (up to 33600 bps).
Technical Specifications
| Parameter | Value |
|---|---|
| Number of channels | 8 |
| PC interface | |
| USB version | 2.0 (full speed) |
| Telephone interface | |
| Type of interface | Two-wire |
| Input resistance (at parallel connection) | 1 MOhm |
| Frequency range | 300-3500 Hz at 8 kHz; 300-7000 Hz at 16 kHz; 300-13000 Hz at 32 kHz |
| Input connector | DB25 |
| Analog interface | |
| Sampling frequency | 8, 16, 32 kHz, quantization being 16 bit |
| Input signal preamplifier | Up to 22.5 dB (increase interval is 1.5 dB) |
| Signal/noise ratio | 78 dB |
| Harmonic factor | -75 dB |
| Intermodulation factor | -70 dB |
| Line voltage measurement | ±200 V accurate within 0.2 V, refresh rate is 200 Hz |
| Peak audio amplitude | Up to ±7V (amplitude) |
| Transmitting signal (speech, tones, CALLER ID) to line | Peak amplitude is +3 dB |
| Galvanic isolation | > 1000 V |
| In-phase rejection | 80 dB |
| Audio processing | |
| AGC range | Up to 18 dB (program preset) |
| Audio compression | G.711, GSM 6.10 |
| Additional functions | |
| Detection of calling signal | From 20 V in the range of 16.7 to 100 Hz |
| Electret microphone support | supply 5 V, 1 kOhm, balanced input |
| Detector of modem and fax transmissions | V.21, V.8bis, Bell202, V.17, V34, V.90, V.92, T.30, V.27ter, V.29, V17. |
| Remote caller number identification | CALLER ID |
| Power supply | |
| +5 VDC | < 300 mA |
| ±12 VDC | +12 V < 200 mA; -12 V 0 mA |
| Operation temperature | from 0°C to +50°C |
| Storage temperature | from -20°C to +70°C |
| Humidity | from 8% to 80% |
| System requirements | |
| Operating system | Windows 2000/XP/2003 |
| RAM | 128 MB for Windows 2000/XP/2003 |
