SMD 989
– User Manual
Page 17 (105)
L-band primary output (50 ohm SMA connector)
L-band monitor output (50 ohm SMA connector -20 dBc from primary)
SMD 940 Option (10MHz Reference on L-Band)
The SMD 940 Option, when used with options SMD 920, adds the capability to combine the L-
Band output with an internal 10MHz oven-controlled crystal oscillator or with an external 10MHz
reference. SMD 940 eliminates the need for an external diplexer. Option 940 is also adds the
capability to combine an external DC to the L-Band output when not used with options SMD 942
and SMD 944 described below. The L-BAND Pri output on the SMD 920 is connected to the
LOOP IN. The L-Band RF, 10MHz and DC are combined at the PRI OUT w/ 10MHz + DC
connector.
Figure 8: SMD 940
SMD 942 Option (24VDC BUC Power & 10MHz on L-Band)
The SMD 942 Option includes option SMD 940 with the additional capability to provide 24VDC
power along with 10MHz and L-Band modulated signal on the same connector. SMD 942
eliminates the need for an external DC supply and external diplexer. The L-BAND Pri output is
connected to the LOOP IN. The L-Band RF, 10MHz and DC are combined at the PRI OUT w/
10MHz + DC connector.
Figure 9: SMD 942 and SMD 944
SMD 944 Option (48VDC BUC Power & 10MHz on L-Band)
The SMD 944 Option includes option SMD 940 with the additional capability to provide 48VDC
power along with 10MHz and L-Band modulated signal on the same connector. SMD 944
eliminates the need for an external DC supply and external diplexer. The L-BAND Pri output is
connected to the LOOP IN. The L-Band RF, 10MHz and DC are combined at the PRI OUT w/
10MHz + DC connector.
