Comtech EFData SDM-300 Satellite Modem is a used 70 MHz modem with QPSK and Viterbi. The maximum data rate of this modem is 512Kb.
The photographs show the modem in IF loopback verifying that the transmit and receive sides of the modem are working perfectly.
Some features taken from the Comtech EFData SDM-300 Satellite Modem specifications
• 2.4 kbit/s to 4.375 Mbit/s
• Fully Accessible System Topology (FAST)
• Intermediate Data Rate (IDR)
• INTELSAT Business Services (IBS)
• Drop and Insert (D&I)
• Automatic Uplink Power Control (AUPC)
• Asynchronous Channel Unit Overhead
• Fast Acquisition
• Built-In Self Test