FLDigi is a handy 3rd party program that interfaces with your FlexRadio using DAX and CAT to allow transmitting and/or receiving a large variety of digital modes, including CW, PSK-31, OLIVER, RTTY, THOR, CONTESTIA, THROB, WEFAX, and many others.
You can download Fldigi from SourceForge: fldigi - Browse /fldigi at SourceForge.net
or from W1HKJ Software
This is a quick pictorial description for configuring a single slice/instance of Fldigi for the FLEX-6000/8000 Series Radios. This is for use WITHOUT using SliceMaster6000. (There is already an excellent tutorial for using SliceMaster)
This tutorial will not cover finer configuration subjects such as configuring operator data, interfacing with logbooks, setting up macros, etc. These and other topics are covered extensively in the Fldigi User Manual: fldigi_help.pdf (w1hkj.com)
You may also find some assistance by watching this video:
FlexRadio SmartSDR with CAT + DAX + FLDigi (youtube.com)
1) Create a Virtual Serial COM Port in CAT:
(This will be used to send control, data, and PTT signals to and from your FlexRadio.)
- Click on the "ADD" button in the CAT Program.
- Give a descriptive "Name" to the Port (Example: "FLDigi_Slice A")
- Select the SERIAL Button to configure a Virtual COM Port.
- Select the FlexVsp button to define this port as a "Virtual COM port"
- Note the COM Port Number the CAT program assigns to this COM Port. (This example is COM13)
- Select the Slice letter that will match the slice receiver used for digital mode operation: (Example: A)
- Click the "Enable Auto-Switch Slice" so that it is BLUE and says "ENABLED."
- Click on the SAVE Button.
2) Download the RigCAT XML Files:
FLdigi makes use of one of many "XML" files to control the communication of commands and data between the radio and the program. There are 8 potential XML files available for the FlexRadio -- one for each possible Slice that might be used with the program. You can download them here:
fldigi - Browse /xmls/flex at SourceForge.net
Download and save the RigCAT XML files to a directory on your computer. Remember where you put them, because you will need to link your FLditi program to one of these files in the next step. (most likely the "SmartSDR_SliceA.xml" file.)
3) Configure the Fldigi Control and Audio settings:
- Open the "Configure > Config Dialog > Rig Control" tab.
- Click on the "Use RigCAT" box.
- In the line "Rig description file:" Click on the "OPEN" button and browse to the directory where you stored the XML files. Select the "SmartSDR_SliceA.xml" file and click the "OPEN" button at the bottom of the window.
- For "Device:", use the pull-down menu to select the COM Port you created in step #1 above.
- The data in the next two rows should not need to be changed.
- In the section with all the "check-boxes," select ONLY the following:
[] CAT Command for PTT
[] VSP Enable
- Click on the Initialize Button. The text in the box should change from RED to BLACK.
- Hit the SAVE button
4) Configure the Fldigi "Sound Card" settings.
In the example below, it is assumed that the DAX channel associated with the slice receiver you will be using for digital mode operation is the same as the one defined to "Auto-Switch Slice" in the CAT port created in Step #1 above.
- Open the "Configure > Config Dialog > Soundcard > Devices" tab.
- Click on the small box labeled "Port Audio."
- Click on the small box labeled "Device Supports Full Duplex."
- Click on the pull-down Menu titled "Capture:"
- Find the Audio Device called "DAX Audio RX 1" and click on it. (This sets the "Receive Audio" device.
- Click on the pull-down Menu titled "Playback:"
- Find the Audio Device called "DAX Audio TX" and click on it. (This sets the "Transmit Audio" device.
- Hit "SAVE"
- Hit CLOSE to close the window.
5) Select the Receive Channel from the DAX Pulldown menu in the "Slice Flag" in SmartSDR.
- Most users select DAX Channel 1 for Slice A.
(This must match the DAX AUDIO RX channel selected for the Soundcard Capture INPUT in Fldigi, above.) - If you wish to use a different RX DAX Channel, you must also change it in the Fldigi Soundcard Capture: "Audio" tab, and select a different RigCAT XML file in step #3 above.
6) Check your settings in the DAX Control Panel
- TX Gain = 45 (this will prevent overdriving the audio input level.)
- RX Stream 1 "Slice A" = 35 (gives a good signal-to-noise ratio (SNR) in Fldigi)
- The "Slice A" notation in RX Streaming 1 indicates that DAX Channel 1 has correctly been selected for "Slice A" (see step 4 above)
- The small square button for RX Streaming Channel 1 should be BLUE. If it is Yellow, click on it. If it does not turn BLUE, check that DAX Channel 1 has been selected in Slice A of your radio. (See step 4 above).
7) Enable the TX DAX Button in the "Radio Controls" Panel > P/CW Sub-Panel (See Yellow Arrow)
- You may also wish to enable the MON (Monitor) so you can hear your own transmitted signal.
You may not want it very loud, however, for comfort. - Do NOT select the +ACC Button above it. It is not needed.
8) Adjust your Fldigi Transmit Audio Output:
- Once you begin a transmission with Fldigi, you will need to fine-tune the Transmit Audio using the left and right arrow keys at the bottom right of the Fldigi screen. There are large and fine adjustment buttons. The Double-arrow buttons adjust in whole dB steps. The single-arrow buttons adjust in tenths of a dB steps.
- Adjust the Fldigi TX Audio output buttons until the Audio Level on the SmartSDR LEVEL Meter reaches just short of the 0 dB (RED) indicator. In this picture, the PEAK Audio LEVEL meter is at about -4. You can run it to about -1 dB safely. DO NOT drive the audio into the RED, or you WILL have distorted signals.
9) Configure your FlexRadio Receive Filters for best Digital Modes operation
Set the Digital Mode Filter to Low Latency. (Turn "Auto" OFF in the Digital Line)
Do NOT check the "Low Latency Filters for Digital Modes" box if you are using WSJT-C Modes. (That setting is primarily for use with PACTOR and other digital modes that require low-latency operation.
10) Additional Consideration:
Create a dedicated Mic Profile for digital mode operation:
- In SmartSDR For Windows: Click on "Profiles > Create Mic Profile." Be sure the "Mic Profile" tab is selected.
- Click in the Box that says "New Profile Name" and name it "DIGITAL."
- Hit "CREATE" and close the menu.
- Now make the appropriate changes to your Mic Profile settings for the Digital Modes:
- This Mic Profile should have the TX DAX button enabled (see above)
- Set the LOW-CUT = 50 and HIGH-CUT = 3100
- Select this Mic Profile from the Mic Profile Pull-down menu; use it whenever you are running the radio in DIGU mode for Digital Modes such as Fldigi, WSJT-X, MMSSTV, etc. Once selected, when in DIGU Mode, the radio will remember it the next time you change to DIGU Mode.
Operation on 60 Meters:
-
Create a different Mic Profile for Digital Modes on 60 Meters. Call it something like "DIGI-60 Meters"
Set the LOW-CUT = 100, and the HIGH-CUT = 2900 to stay within the 60 Meter Frequency allocation. Use this Mic Profile when doing Digital Modes on 60 Meters (and be certain that the radio stays on the assigned "carrier" frequency when transmitting.)
MULTIPLE SLICES / MULTIPLE INSTANCES of FLdigi:
How to use FLDigi with two slices has already been explained on this forum
https://community.flexradio.com/flexradio/topics/new-fldigi-rigcat-files-for-so2r-capability
This is also easily configured using the 3rd Party application "SliceMaster 6000"
GitHub - K1DBO/slice-master-6000: Additional slice controls for your Flex 6000 series radio
Don has an excellent tutorial on his website for configuring Digital Modes, such as Fldigi, WSJT-X, and others.
Now you should be able to operate the new Digital Modes with Fldigi!
Enjoy the new modes!