If you haven’t done so yet, you should read my previous article, ‘Installing and Configuring Device Drivers for the Yaesu FTDX101D’ since you will need to have completed that installation before any of the following will work.

I’m also assuming that you’ve already downloaded and installed the N3FJP logger on your computer and are ready to go.

This first section is performed to allow you to connect to the advanced COM port which is used to perform rig control. This allows you to control the frequency of the radio, change modes, etc.

• Launch N3FJP logger and go to ‘Settings’ > ‘Rig Interface…’.
• You will now enter configuration information that matches the values that you used when installing the Yaesu device drivers. See the previous article that I mentioned above for more info.
• Enter the following information in the appropriate sections:
  • ‘Select Rig’ – ‘Yaesu Newer 2’
  • ‘Com Port’ – the COM port associated with your advanced COM port. In my case it was ‘COM4’.
  • ‘Baud Rate’ – ‘38.4’
  • ‘Parity’ – ‘None’
  • ‘Data Bits’ – ‘8’
  • ‘Stop Bits’ – ‘2’
  • ‘Connection Power’ – ‘None’
  • ‘Radio Polling Rate’ – ‘2 sec’
  • ‘Mode Determined by’ – ‘Rig’
• Make sure that the following items are checked:
  • ‘Use Frequency on Main Form’
  • ‘Immediately Execute Commands’
  • ‘Enable Ctrl Key Keyboard Tuning’
  • ‘Block Band Overlap’
• Set the following text into the associated text boxes:
  • ‘Command to Read Frequency’ – ‘FA;’
  • ‘Command to Read Mode’ – ‘MD0;’
• After entering the above information, press the ‘Test’ button to start polling the rig. You should see the frequency and mode updating every two seconds which means you are receiving data from the rig.
• Next, test the ability to control the rig by setting a frequency in the bottom right corner of the screen and pressing the ‘Send’ button. Your rig should jump to that frequency. You can also press one of the mode keys to verify that the rig will change modes properly.
• Press ‘Done’ to dismiss the dialog.

This next section is performed to allow you to connect to the standard COM port which is used to key the transmitter.

• Go to ‘Settings’ > ‘Transmit’ > ‘CW Setup’ and set the following:
  • ‘Com Port’ – the COM port associated with your standard COM port. In my case it was ‘COM3’.
  • ‘Keying Options’ – ‘DTR’
• To test the setup, press the ‘Test’ button which will start transmitting the text contained in the F9 box. To abort the test, press .
• If this worked, press ‘Done’ to dismiss the dialog and you are ready to go. If not, you’ll have some troubleshooting to do. If you’re having a keying problem, verify that the COM3 settings you entered here, match those you did during the standard driver installation. If you’re having a rig control problem, verify that the COM4 settings you entered here, match those you did during the standard driver installation.

That’s it. It’s not really all that bad. The thing to remember is that you can uses many different combinations of device settings to control your rig but in order for them to work, both your software and your drivers must use the same settings. The settings I’ve used above have been tested and are known to work so I encourage you to use the same values.

N1MM Logger appears to be the logging program of choice for amateur radio contests. A lot of hams use it as a contesting log because of it’s many contesting features but after the contest is completed will export the data to another general logger that they use to log all of their contacts.

N1MM allows you to automate a lot of the steps when contesting. For example, when using Morse code, you can load a configuration for a state QSO party, and just press function keys to perform the contesting exchange instead of using a Morse key and doing it manually. While this may seem like cheating to some, contesters like it because of the quick turnaround of contacts, beginners like it because they are prone to making sending mistakes and other like it because it’s just easier than sending code manually. For the automatic features to work, the program needs to be able to communicate with your radio. The rest of this article will tell you how to do that.

Note that I’m using a Yaesu FTDX101D radio during this procedure but any Yaesu radio should have a similar setup and other non-Yaesu radios will probably work pretty much the same with some minor tweaks to the process.

Here’s how to do it…

• Launch N1MM Logger and select ‘Config’ > ‘Config Ports, Mode Control, Winkey, etc…’ then select the ‘Hardware’ tab.

• At the top of the dialog you will see three radio boxes, these are used to select the type of hardware configuration you are using.
  • ‘SO1V’ is the simplest. It used when your radio has just one VFO that you will be using for both transmitting and receiving.
  • ‘SO2V’ is used when your radio has two VFOs. Selecting this will configure the program to work with both and will display two separate dialogs during normal operation with each one allowing you to control a separate VFO. For example, one dialog/VFO could be used to work the 20M band, while the second could be used to work the 40M band.
  • ‘S02R’ is similar to ‘SO2V’ except instead of controlling to VFOs on the same radio, you are controlling to separate radios.
• To keep things simple, even though the FTDX101D contains 2 VFOs, I’m only using one and thus will select ‘SO1V’.

• Next, we’ll set up CAT control for N1MM. This allows the software to control the radio and do things like change and read frequencies, modes and bands. It also enables the software to read and set many of the parameters used by the radio. On Yaesu radios, CAT control is accomplished using the Enhanced COM port and on my computer it is mapped to COM4, so on the first line we set ‘Port’ to ‘COM4’ and ‘Radio’ to ‘FTDX101D’. The ‘Radio’ field is used by the program so that it understands what messages to use during communications and what features are supported.

• Now press the ‘Set’ button and set the following values:
  • ‘Speed’ to ‘38400’
  • ‘Parity’ to ‘N’
  • ‘Databits’ to ‘8’
  • ‘Stop Bits’ to ‘2’
  • ‘DTR’ to ‘Always Off’
  • ‘RTS’ to ‘Always Off’
  • ‘Radio Nr’ to ‘1’
• Select ‘OK’ to save the changes. We use these values because they match the values we used when we configured the radio and the drivers in the previous article. They describe the speed and rules that the radio, computer an N1MM use to talk to each other. You can use different values if you like but just make sure they are consistent between all three devices.
• In this step, we set up keying for N1MM. This allows the software to key the radio instead of you having to push a button or press a Morse key. On Yaesu radios, this is done using the Standard COM port. On the second line of the dialog, select the port that’s mapped to your standard COM port, for me it’s ‘COM3’, leave the ‘Radio’ set to ‘None’, and check the ‘CW/Other’ check box.

• Press the ‘Set’ button and set the following:
  • ‘DTR’ to ‘CW’
  • ‘RTS’ to ‘PTT’
• Select ‘OK’ to save the changes and ‘OK’ a second time to close the ‘Configurer’ dialog. This setup is simpler than the one for the Advanced COM port because there’s no data transfer involved, Yaesu keys the radio based only on the state of the DTR pin or the RTS pin. So essentially, only a single line is used on this port.
• Finally, verify that CAT control works by tuning your receiver and seeing if the N1MM frequency display in the title bar of your dialog updates. As a second check, click on one of the bands in N1MM and see if it changes the band on your radio. If these tests fail something is wrong with your enhanced com port settings you will need to troubleshoot it. You can check to make sure that keying is taking place by connecting your radio to a dummy load, turning down the power and pressing one of the function keys used during an exchange. If everything is working your radio should start transmitting and you will hear keying taking place.

This document is an attempt to explain the connections that are needed to interface a computer with the Yaesu FTDX101D, what each of those connections does and what you need to do to get your computer talking to your rig. While it’s written for the FTDX101D, I suspect the same information will apply to any modern Yaesu transceiver and with some minor changes could also be used to set up non-Yaesu rigs.

Connecting your computer to your transceiver allows you to do all sorts of interesting things. You can control your rig from your computer, automate the logging process, run software that allows you to communicate with others using the various digital modes and many other things.

While researching the connection process, I came across a lot of good information, some bad information and found that although many people were able to connect the two devices, a lot of them didn’t really understand what was going on when they did it. I hope to clear that up here.

There are four different connections that need to take place when you connect to your radio with each one serving a particular purpose.

The first is for CAT (Computer Aided Transceiver) control. This allows the computer to send commands to the radio and receive back responses enabling you to do things like change your rigs frequency and mode and read back parameters like SWR and power, etc.

The second connection is for keying the rig. You want your computer to be able to tell your transceiver when to transmit and when to stop transmitting so it can automatically send and receive data.

The next connection is for sending audio to your rig. This is required to modulate the carrier for digital modes or for sending prerecorded audio.

The final connection is used to receive audio from your rig. Doing this allows software on your computer to ‘listen’ to the rig, giving it the ability to do things like decode Morse code or interpret digital mode messages.

In the old days, interfacing with a radio was complex and required two different cables. CAT control took place through an RS-232 cable while RTTY/Data, audio input and output and transmitter keying were done using a special 6-pin Mini-DIN data/packet connector cable. In modern setups, both of these cables have been replaced with a single USB cable which greatly simplifies the connection process. Unfortunately, the connection process is a bit confusing because the industry has implemented the USB interface in a way that emulates the old two cable method making it more complex than it really needs to be.

On Yaesu radios, you install a set of drivers that connect to the computer hardware and present an interface through which your programs (WSJT-X, JS8Call, fldigi, Ham Radio Deluxe, etc) can talk to the radio. The driver installation creates two virtual COM ports (Enhanced COM Port, Standard COM Port) and two audio devices (Line USB Audio CODEC), (Speakers USB Audio CODEC).

Enhanced COM Port is used for CAT control. It sends commands to the rig and receives back responses allowing the computer control the radio and read the various settings and parameters. This acts as the equivalent of the RS-232 cable.

Standard COM Port is used strictly for keying the transmitter. This takes the place of the 6-pin Mini-DIN connector cable. One of the things that’s interesting with this connection is that only the DTR or RTS line is used for keying the rig, so it really doesn’t matter what setting you use for baud rate, parity, etc. (Even though it doesn’t matter, later in the procedure I use the same settings that I use for the enhanced port, just to make them consistent).

Line USB Audio CODEC sends audio information from your computer to your radio allowing it to modulate the carrier and transmit information. This connection used to be part of the 6-pin Mini-DIN connector cable.

Speakers USB Audio CODEC receives audio from your radio allowing it to decode the audio and present it as Morse code or digital mode data.

Installing and Configuring the Drivers

• Go to the Yaesu website and navigate to the FTDX101D page. Select ‘Files’ and click on the ‘FTDX101MP/D USB Driver Virtual COM Port Driver (Windows 11/10)’ link towards the bottom of the page. This should download the file ‘CP210x_Universal_Windows_Driver.zip’ to you computer.
• Right-click on the file, select ‘Extract All…’ and press the ‘Extract’ button.
• After the files have been extracted, right-click on the ‘silabser.inf’ file, select ‘Install’ and then press the ‘Open’ button and follow the prompts to install the driver.
• Open Windows Device Manager, click on ‘Ports (COM & LPT)’ and verify that you have two ‘Silicon Labs Dual CP2105 USB entries’. While doing this, take note of the COM port numbers used for each device since you will need this information later in the process. On my system ‘COM4’ was used for ‘Enhanced’ and ‘COM3’ for ‘Standard’ but your values may be different.

• Double-click on the ‘Enhanced’ port entry, navigate to ‘Port Settings’ and verify the settings are as follows, changing the values if needed. If you look around the Internet you may see many different values set for these parameters. This is because the values you use aren’t critical as long as both the radio and computer use the same values. It’s like talking to someone in French, if both of you are using speaking French, everything is fine but if one of you is speaking French while the other is speaking German, nothing good will come of it.
  • ‘Bits per second:’ ‘38400’
  • ‘Data bits:’ ‘8’
  • ‘Parity:’ ‘None’
  • ‘Stop bits:’ ‘2’
  • ‘Flow control:’ ‘None’

• Double-click on the ‘Standard’ port entry, navigate to ‘Port Settings’ and enter the same values you used for the ‘Enhanced’ port.
• You can now delete the CP210x zip file and folder since they’re no longer needed.

Configuring the Yaesu FTDX101D

• On the FTDX101D, press the ‘FUNC’ button, then select ‘Operation Setting’>’General’.
• Set the following parameters:
  • ‘CAT RATE’: ‘38400bps’
  • ‘CAT TIME OUT TIMER’: ‘100msec’
  • CAT RTS’: ‘OFF’

• Press the ‘BACK’ button to back out of the current screen and the select ‘CW SETTING’ > ‘MODE CW’. Find ‘PC KEYING’ and set it to ‘DTR’.

• And you’re done. These settings should allow your radio to work with any program you install as long as the program configuration matches the values you’ve used here. I’ll soon be posting setup information for other programs like WSJT-X, N1MM Logger and N3FJP Logger which will show you how it’s done.

VC-Tune (Variable Capacitor Tune) – it can attenuate interfering signals directly at the receiving frequency.  It can be turned on to attenuate the strong jamming signals that cannot be removed even with BPF (Band Pass Filter).  If there is no interfering signal, turn it off. 

The VC tuning circuit works by driving a variable capacitor in the receivers front end with a stepper motor.  It attenuates the strong intruding signals that are problematic.

There are two VC Tune buttons located to the right of the main dial.  The bottom button (VC tune operations key) will enable VC tuning and center itself on the current operating frequency.

The top button on the right of the main dial, enables VC tune but also activates the MPVD ring allowing you to shift the location of the VC tuning.  If you press it a second time, it will release control of the MPVD ring (leaving the current tuning location in place) and set the MPVD ring to control the main frequency.  (It would have been nice if they MPVD ring reverted to it’s last assignment instead of defaulting to controlling the main frequency.)

You can see the current tuning position by looking at the pointer on the VC Tune bar graph.

In most cases you will probably want to use the top VC tune button to activate VC tuning since it gives you more control.  Just make sure that you press both the top and bottom button when done to fully deactivate VC tuning. 

If you change the current frequency, you can recenter VC tuning by pressing and holding the either of the VC Tune keys.

VC tune only works on the main band, VC tune for the sub band is an optional add-on.