Flex Radio SmartSDR for Mac

I've been contemplating pulling the trigger on the purchase of Flex Radio's SmartSDR for MacOS for quite some time. My club, 285 Tech Connect (NA0TC), has a remote station out in Strasburg Colorado which features a Flex 6400 along with an antenna tuner connected to a fan dipole, which gives coverage over several of the HF bands including 10/15/17/20/40 meters.

Flex provides their remote control software, SmartSDR, free only for Windows PCs, and as I'm primarily a Mac person, I've been wanting to pick up their Mac version for a while. It's $99 to purchase, which compared with free, is a bit steep IMO. That said, I finally decided to purchase it yesterday and I haven't been disappointed.

I should mention that SmartSDR for Mac and iOS is actually written and sold by a third party, Marcus Roskosch, who I believe makes a living doing this. So I can definitely understand why he has to charge for it. On the positive side, in addition to supporting an independent software developer, Marcus' software also provides considerably more functionality than the free Windows version. I previously purchased SmartSDR for iOS and have been very impressed with the software, especially since it allows me to use my iPad with the Flex. So I had a good feeling that the MacOS version would also be excellent--and I wasn't disappointed. 

One really cool thing about the Mac version of SmartSDR is all of the added functionality. In addition to the basic radio control capabilities like rig control, transmit/receive using phone/CW/digital, etc., the app comes with a ton of added features including FT8/FT4, logging (including integration with QRZ/LoTW/etc), RTTY, PSKReporter, POTA, a CW decoder, and more. Here's a table that outlines all of the features of the three SmartSDR versions (if you have a hard time reading this, the full version is available here).

Interestingly, his website lists the Mac version for $159 but I purchased it via the Mac App Store yesterday for $99. 

After purchasing and installing the software, the process of connecting to the Flex SmartLink website was very simple, as was testing the connectivity to the radio, which can automatically configure your router for the required ports, assuming you have uPnP port forwarding enabled. 

I did run into a small issue, which also exists in the Windows version (but doesn't seem to be a problem on iOS): the MTU (maximum transmission unit) network setting, which defaults to 1500, needs to be adjusted down to 1438 ideally. The symptom is that SmartSDR can see the radio and attempts to connect to it, but times out with no connection. 

On the Mac, you can find the MTU setting by going into settings...network and then opening up the network adapter you're using (in my case it's "WiFi"). Click on the Details button, then click on Hardware on the left side of the screen. You then have to click on "Configure", set it to "Manually" and then you can override the default MTU. The issue arises around the size...MacOS only allows the range of 1280-1436...so 1438 is not an option. Fortunately, it's possible to select 1436 and it works just fine. My Mac is running MacOS Sonoma (the latest release at the time of this writing) so your screens may look different if you're using a different version of MacOS.

After changing the MTU version, SmartSDR connected and I was off to the races. After familiarizing myself with the user interface, which is very similar to the Windows and iOS versions, I went through the various settings screens to add my callsign, grid square, etc. Then I fired up the FT8 app and started playing around. Unfortunately, even though it's technically possible to use the native WSJT-X app with SmartSDR, it's not trivial to get it working, requiring using virtual sound drivers etc. I haven't tried that yet. Fortunately, the built-in SmartSDR FT8/FT4 app works just fine--and has features even WSJT-X doesn't have, including showing received callsigns on the waterfall, a combined RF waterfall and FT8 waterfall, automatic logging (no user interaction required), and the ability to automatically start another CQ series after completing a QSO. 

Within an hour or so, thanks to the awesome location of our remote station, I'd completed FT8 and FT4 QSOs with stations all over the world, including snagging a new country (Mauru). So it definitely works!

In the near future I plan on trying out the voice and CW capabilities of the software; I'll report back when I've had more time to play with it. In the meantime, if you have access to a Flex radio and are a Mac or iOS user, definitely consider getting Marcus's SmartSDR!

73,

Mark