Slides from RCARCS 7/3/18 meeting: Intro to FT8 Digital Mode

I presented an overview of the incredibly popular FT8 digital mode at the River City ARCS club meeting on 7/3/18.

Here’s a copy of my slides:

Instead of disassembling my HF station and taking it into the meeting, I tried something different and demo’d using the mode (to receive) using WebSDR, and to transmit using a remote station provided by . We operated the W1/Chaplain, CT station on the East coast, and worked 3 stations in Europe – HA1RB, DL2LDE and DG6YID during the meeting. From this East coast station the 40m section where FT8 is operated on 7.074Mhz was completely packed from edge to edge on the waterfall!

Piping audio between applications: Configuring ham radio apps on Mac OS using SoundFlower (virtual audio cables)

You’re running some digital mode software like WSJT-X on your Mac. Normally you would use a physical audio cable between your radio to your Mac, either via a soundcard interface like a Rigblaster, or even a direct USB connection to your Mac and your radio. What happens though if you want to route your audio from one application to another? For example, can you pipe the audio from a Web SDR running in your browser straight into WSJT-X (or any other digital mode software)? What you need are ‘virtual audio cables’.

On Windows you have a product called VB-Cable (the approach for Windows is similar to what’s described here). On MacOS you have a couple of options. There’s a commercial product called Loopback from Rogue Amoeba, or an open source alternative called Soundflower.

Follow the instructions to download and install. Once installed, you’ll find a couple of extra sound devices in your System Preferences:

Think of the Soundflower device as your cable. Instead of configuring Speakers for output and Mic for input, if you configure the input for one app as Soundflower (one end of the virtual cable) and the output for another app also as Soundflower (the other end of the cable), and sound output from one app is now directed into input of the other.

Let’s give this a go to connect the output from a WebSDR with the input to WSJT-X.

First, from System Preferences, select the Output to be Soundflower (shown above).

Start up a browser and pick a Web SDR station from

Here’s KFS and we’re tuned in to 7.074Mhz USB to receive some FT8:

Next, start up WSJT-X and go to Preferences, Audio:

Note that with Input = Soundflower we’re routing the Output audio from the WebSDR running in the browser into the Soundflower virtual cable. From WSJT-X we’re then taking the audio from this virtual cable as the input into WSJT-X, effectively routing the audio from the web browser into WSJT-X.

Also note that with Output = Soundflower in WSJT-X, if we transmit on WSJT-X the audio will also go out on the virtual cable. With WebSDR we can’t obviously transmit, but if you have access to a remote rig like, you can route the audio from WSJT-X into the remote rig app. More on that coming next.

You might note that with this current configuration there’s no actual audio coming out of your speakers. With some virtual cables you have the option to monitor the audio passing over the virtual cable. On MacOS you also have the ability to create composite audio devices using the Audio MIDI Setup app:

This shows a ‘Multi-Output Device’ comprising both the regular built-in audio (your speakers) and Soundflower. Now you’ve got the best of both worlds. More on this next step, and also configuring to use with WSJT-X coming up next.

Is it worth running Windows just to use Ham Radio Deluxe?

I spent some time over the weekend using Ham Radio Deluxe running on an HP Mini netbook, and came to the conclusion that the netbook doesn’t really have enough horsepower to give a good experience with HRD. It’s just too sluggish opening the apps and moving back and forward between the Log app and the DM780 digital modes app. I did enjoy having the ability to automatically log my QSOs though, so I’ve spent some more time to investigate how I can make better use of the apps I’ve been using up until now on my Mac.

Turns out that RUMLog will watch the log files from FLDIGI and automatically copy new logged QSOs across from FLDIGI, so this is a good step in the right direction. For JT65-OSX, although it’s not automated, it will write to an ADIF file and then you can import that into RUMLog manually, so that’s better than nothing.

Sorry HRD, you’re just too bloated and I’m not interested in buying a new Windows machine just to run you. For now I think I’m going back to the apps I was already using on my Mac. Turns out RUMLog is actually pretty good 🙂

Ham Radio Deluxe 5.24 – PSK macros won’t save

As a Mac user and a new ham operator starting to play with digital modes (mainly JT65, PSK31 and RTTY) I’ve been envious of the variety of Windows based apps available compared to what’s available on the Mac. For the past few weeks I’ve been mainly using the following:

These have all been working fine, but from seeing videos online of people using HRD and the integrated digital mode app together with the HRD logging, it kept bothering me every time I had to manually type in details from a QSO into my logging app.

Since we have a HP Mini netbook running Windows 7, I decided to check out the still (up until fairly recently) free version of Ham Radio Deluxe (5.24), and was surprised to find I couldn’t work out how to make my updates to my PSK macros save. Every time I made changes in the Macro Manager, they would never be reflected in the app.

It turns out that from a new installation, HRD either protects the directory where your macros files are saved, and/or installs the default macro files as read-only, so no matter what you do in the app, you can never save any updates to your macro files. What’s worse, the app doesn’t give any indication that it’s failing to save your updates, it just carries on regardless.

Luckily I can across  this thread and once I took off the r/o flag on the macro files I was able to save my edits.

Now that HRD 6.x+ is $100, I’m not sure if I’m that enthusiastic about spending $100 on an app that doesn’t by default allow me to customize my preferences, and worse still, doesn’t tell me when something is failing (incorrect permissions to write to a file). Still, I am impressed with the digital modes and log integration, so I’m going to be trying it out for a while and see how it goes.