Comtech EF Data SFC4200 - Manual (Page 44)

User Interfaces SFC4200/SFC1275G Synthesized Frequency Downconverter
4-20 TM054 - Rev. 4.0
4.5 Control Commands
Control Commands are those commands that alter the setup or operating parameters of the
converter. These commands primarily control Frequency and Gain. Frequency and Gain can be
altered on the current channel number that is indicated on the front panel, or the other channels
0-30 which are not selected can be programmed without affecting the current operating channel.
The final method to change Frequency and Gain is by remotely recalling the Gain and
Frequency Settings that have been programmed in another channel. The various Control
Commands are applicable for a variety of converter configurations. After each of the following
control commands appears an abbreviation in parenthesis that identifies which converter
configurations are valid for that particular control command. The applicable converter
configurations are as follows:
S: Single Converters
P1:1: Primary Converter 1:1 Switch
B1:1: Backup Converter 1:1 Switch
P1:8: Primary Converter 1:8 Switch
B1:8: Backup Converter 1:8 Switch
ALL: All Converters
4.5.1 Set Current Channel Frequency Command (S, P1:1, P1:8)
The Set Current Channel Frequency Command alters the stored frequency of the current
channel. The set frequency command is as follows:
@01/SETFREQffff.t<cr>
The frequency numerical values include four digits for MHz and one digit "t" which indicates the
resolution in 125 kHz steps. The values of "t" are as follows:
t Frequency
0 000 kHz
1 125 kHz
2 250 kHz
3 375 kHz
4 500 kHz
5 625 kHz
6 750 kHz
7 875 kHz
Valid frequency ranges are 3400.000 though 4200.000 kHz (SFC4200), and 10950.000 MHz
through 12750 MHz (SFC1275G). Frequencies outside this range, or frequencies that are of an
invalid form will be responded to by the ‘illegal frequency’ prompt. If the synthesizer is unable to
tune to the desired in-band frequency, the converter will indicate a LO Fault Condition status
indication and will change to an off-line or out-of-service indication.
4.5.2 Set Current Channel Gain Command (S, P1:1, P1:8)
To permanently change the programmed gain of the current channel, use the Set Current
Channel Gain Command. The command is as follows:
@01/SETGAINsgg.g<cr>
The numeric value ‘s’ indicates the ‘plus’ sign (+). The numeric value ‘g’ consists of three digits
indicating gain from 0 to 40 dB.