Comtech EF Data CDM-700 - Manual (Page 146)

CDM-700 High Speed Satellite Modem Revision 5
Summary of Specifications MN/CDM700.IOM
10–4
10.3 70/ 140 MHz Modulator
Item Requirement
IF Frequency
52 to 88MHz / 104 to 176MHz (100Hz steps). Bandwidth of spectrum is
contained within IF frequency range.
Impedance 50 / 75
Ω programmable
Return Loss 18 dB min
IF Connectors BNC, female
Output Power
0 to -20 dBm, 0.1 dB steps. Carrier is not interrupted changing between
any levels or removing data connections.
Accuracy
± 0.5 dB nominal at 25
°C. Within ± 0.5 dB of room temperature value
over frequency and temperature range.
Harmonics & Spurs <-55 dBc/4 kHz over 40 to 250 MHz with modulated carrier
Phase Noise < 1 degrees RMS double-sided, 100 Hz to 1 MHz
External Tx Carrier Off TTL low signal – path to shutoff bypasses microprocessor.
Quadrature Phase Error < 2
°
Amplitude Imbalance (I, Q) 0.2 dB maximum
Combined Amplitude Imbalance and
Quadrature Phase Error Single sideband test with suppressed sideband 35 dB minimum below
unmodulated carrier.
Carrier Null 35 dB minimum below an unmodulated carrier.
Frequency Inversion Normal or Inverted
10.4 L-Band Modulator
Item Requirement
L-Band Frequency 950 to 1950 MHz in 100 Hz steps.
Impedance 50
Ω
Return Loss 14 dB min
IF Connectors Type N female or optional SMA female
Output Power
-5 to -25 dBm, 0.1 dB steps. Carrier is not interrupted changing
between any levels or removing data connections.
Accuracy (Main Output)
± 0.5 dB nominal at room temperature. Within ± 0.5 dB of room
temperature value over frequency and temperature range.
Monitor Output
Available in Tx only configuration. -20 dB
± 3 dB from main
output.
Harmonics & Spurs <-55 dBc/4 kHz over 800 to 2500 MHz with modulated carrier
Phase Noise < 1 degree RMS double-sided, 100 Hz to 1 MHz
External Tx Carrier Off TTL low signal – path to shutoff bypasses microprocessor.
Quadrature Phase Error < 2
°