:CHANnel:FSELect
Command Syntax
:CHANnel{1:8}{A|B|C|D}:FSELect {FILTer1 | FILTer2 | … | FILTer25}
Where the required specifier {1:8}{A|B|C|D} identifies a channel by its module slot number and channel letter. For example, channel 3C (CHANnel3C).
The channel specifier will fail if it does not include a slot number. If instead the suffix's channel letter is missing, the command defaults to letter A. As a result, the best practice is to always explicitly specify the channel by including both the module slot number and channel letter.
Query Syntax
:CHANnel{1:8}{A|B|C|D}:FSELect?
Description
On an optical module, selects a reference filter from up to 25 possible, depending on the module. The command argument identifies a reference filter that is shown in the Reference Filter field of the channel Setup dialog. For example, FILTer3 identifies the third setting from the top in the listing, 10.31250 Gb/s, as shown in this picture. Use the :CHANnel:FILTer command to enable or disable the filter.
Recommended Alternative
The following commands are the preferred method of setting the channel's filter as they set the value explicitly rather than implicitly thereby making your code more reliable and easier to read:
- Reference filter by Rate (bits-per-second):
- To select rate, use
:CHANnel:FSELect:RATe - To select maximum rate, use
:CHANnel:FSELect:RATe:MAXimum - To select minimum rate, use
:CHANnel:FSELect:RATe:MINimum - To query the list of available rates, use
:CHANnel:FSELect:RATe:VSET? - Reference filter by 3 dB BW bandwidth:
- To select bandwidth, use
:CHANnel:BANDwidth:RATe - To select maximum bandwidth, use
:CHANnel:BANDwidth:RATe:MAXimum - To select minimum bandwidth, use
:CHANnel:BANDwidth:RATe:MINimum - To query the list of available filters by bandwidth, use
:CHANnel:>BANDwidth:RATe:VSET?
On 86105C and 86115D modules, any available extinction-ratio correction factor is automatically applied for extintion ratio measurements when :MEASure:ERATio:CHAN<N>:ACFactor is set to ON.
When making TDEC compliance measurements, a reference receiver 25 Gb/s filter (effective 12.6 BW) is needed. The 86105D and 86115D modules with option 168 include the required filter. To select the filter, select the TDEC (12.6 GHz) filter.
Simulated optical modules do not support reference filters. Sending this command has no affect on simulated optical modules.
Example
The following command selects the third supported reference filter.
:CHANnel2A:FSELect FILTer3
or
:CHANnel2A:FSELect:RATe 10.3125E9