Comtech EF Data SNM-1010L - Manual (Page 115)

SNM-1010L Data/Control Modem Revision 0
Front Panel Operation MN/SNM1010L.OM
LO = 7975 MHz, Mix = "-"
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TX Freq(Max) = 7975 - 950 = 7025 MHz
[L-Band Freq = 950 MHz]
TX Freq(Min) = 7975 - 1750 = 6225 MHz [L-Band Freq = 1750 MHz]
LO = 13050 MHz, Mix = "+"
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TX Freq(Max) = 13050 + 1750 = 14800 MHz
[L-Band Freq = 1750 MHz]
TX Freq(Min) = 13050 + 950 = 14000 MHz [L-Band Freq = 950 MHz]
LO = 15450 MHz, Mix = "-"
-------------------------
TX Freq(Max) = 15450 - 950 = 14500 MHz
[L-Band Freq = 950 MHz]
TX Freq(Min) = 15450 - 1750 = 13700 MHz [L-Band Freq = 1750 MHz]
3.4.7 RX Terminal (Future Provision)
Note: The SNM-1010L automatically configures itself using the L-Band frequency
range. In the future, C-Band/K-Band/Ku-Band frequency ranges may be supported.
Currently the RX terminal LO should be set to zero (0).
This menu allows the user to enter the LO (always in MHz) of the LNB unit. When any
non-zero frequency is entered, the low and high limits of the RX-IF Frequency will have
new ranges (from L-Band to C-BAND/K-BAND/Ku-BAND).
The following formulas are used to calculate the RX frequency range when the MIX is
set "-":
RX Freq(MAX) =
LO - 950 MHz
RX Freq(MIN) = LO - 1750 MHz
The following formulas are used to calculate the RX frequency range when the MIX is
set "+":
RX Freq(MAX) =
LO + 1750 MHz
RX Freq(MIN) = LO + 950 MHz
L-Band frequency of the modem is then programmed via the following Formula:
Freq (L-Band) = ABS (RX Freq - LO).
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