Features: 1.A criterion frame 1U、19 inch with exhaust fans inside. 2. Working bandwidth: 5-65MHz. 3. MGS controlling pattern. 4. Digital gain circuity control the output level reached to 40Bb. 5. Low optical power receiving: the minimum -16 dB m. 6.Four path receive optical respectively. 7. It can fix two options of optical receiving which can choose one from two and this path can auto 杝witched. 8.RS232 network management interface and RS485 concatenation interface.