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My Weekend Test of FT-8

It gets through, even on a compromised antenna

I haven’t been keeping up with my QST magazine reading but had heard about FT8 when it showed up online at some point in 2017. When my friend Clyde Feero VE7CKF mentioned he had set it up recently I knew it was time for me to try it out too.  So this weekend I decided I should spend some time reading about FT8 and see what all the hype is actually about. I watched some YouTube videos and I decided to set it up myself. It was far easier than I thought it would be.

First let me give you an idea of my previous experience with digital modes. I have made less than 100 contacts using PSK31 on Ham Radio Deluxe Digital Master 780. I’ve used it enough to confirm my abilities and my shack’s setup.  I have an iCom 7300 with an end fed wire and 20m dipole for antennas. Both of my antennas are very low from to ground at only about 8 feet up. Even with this compromised antenna system, I’ve made PSK31 contacts as far as South America and Europe.

FT8 is one of the newest digital modes available to amateur radio operators.  It is very popular with anyone wanting to make distant contacts using low power or compromised antennas.  If you’ve ever thought about trying a digital mode like JT65 or PSK31 you might just want to try FT8 for yourself.

Compared to the DM780/PSK31 I found WSJTX/FT8 extremely simple only requiring a few things. You need to configure your radio, sound card and enter your callsign/gridsquare.  With DM780/PSK31 you need to setup some macros. I setup WSJTX software in as little as 5-10 minutes. If your like me and use Ham Radio Deluxe you can still use it for advanced rig control and use WSJTX for FT8. It has an option to select HRD as your radio.  There are also logging abilities supported by WSJTX but I didn’t experiment with them yet. LOTW is still being setup to accept FT8 contacts and contesters are waiting for N1MM to support FT8 as a mode, but it’s only a matter of time.

An FT8 QSO exchange is completely automated by the software. There is an option to perform each step in the QSO exchange manually but when it comes to digital modes there seems to be some desire to have everyone follow a common flow. You probably won’t be actually having a conversation with basic FT8 but instead a quick exchange of contact info.

It’s important that your computer’s clock be accurate because every 15 seconds a cycle completes and a new one begins. If you monitor for awhile you’ll notice every 15 seconds call signs will show up.  Some of the call signs are people calling CQ and others are those in the middle of their QSO exchanges. I’ve provided some reference links below and you can setup NTP (Network Time Protocol) to keep your PC clock in sync.

When you respond to CQ you’ll be sending your callsign and grid square. So this can be a little confusing at first when you notice the callsigns and other numbers displayed. You only need to double click on a CQ and the software will start transmitting. If the contact responds back to you they will send you your signal report. Once you each have these details your 73’s begin and your finished with your QSO.

I made my first FT8 contact with N4CAP Jeff Clouse in Jamestown North Carolina, who was 3857 km away from me using the grid square reference.  I was only running 25 watts on 20 meters and I must emphasize that for me to make this contact I just picked his call sign in a list I saw every 15 seconds.  I then double clicked his call sign on my mousepad.  I did nothing else!! Yes it was just that easy.

You can view a screenshot [right] but the software automatically sent him my callsign and grid square. He then responded to me giving me a -22db signal report. I sent him a -14db signal report for his CQ call. He sent me a roger roger 73 and I returned with a 73. End of call, and he began to call CQ again. All of this took less than 1 minute 15 seconds!!

Call it beginners luck I guess but I tried a second contact and didn’t have the same success I had the first time.  You can view [below] where I responded to the CQ of W1JGM but he didn’t answer me. Since I was already monitoring his frequency I noticed someone else exchanging with him and the software stopped transmitting automatically. When the exchange was done I only needed to time my ‘Enable Tx’ again to try a second time. This is where the computer clock and the 15 seconds cycle applies.  I needed to transmit during the send period and not after. I had no luck, but again it either means he could not hear me or chose not to respond to my weak signal.

To get setup for FT8 you’ll need to download and install WSJTX software for your computer.  Since it is available on Windows, Linux, and Mac I decided to try setting it up on my MacBook. This is my first attempt at using digital modes on my Macbook using Apple’s native MacOS, but have previously used Windows on BootCamp for HRD.

For me using the iCom 7300 for digital modes is a little easier than some radios because it is essentially seen as a sound card when you plug in via USB to a computer; so I didn’t need to use a SignalLink sound card. The WSJTX software lets you pick which audio interfaces you want to use and has a huge selection of predefined radios for CAT control.  There is also a “Test CAT” and “Test PTT” feature so you’ll at least be able to confirm your radio is connected well.

Some advanced setup steps might be required to ensure your radio is setup for data mode and not SSB.  You’ll want to confirm your power output is low 25 watts or less to start with and the ALC is not overdriving the radio.  Your computer will be sending audio to the radio and it may be too strong and overdrive the transmission. The main reason you don’t want to overdrive the transmission is to keep your signal clean and not produce splatter.

While I was trying to respond to a few CQ calls that didn’t get picked up I did notice my signal was getting out all over the world.  Kazuhiko Nishimura JG0CQK located near Japan’s Eastern coastline was approximately 7453 km away picked up my attempts at answering other calls in North America. How do I know this? Well the site supports FT8 mode and provides me this info along with all the other stations that received my transmissions.  This is an excellent tool for proving the low power/efficiency of the FT8 mode at my station without even making a single contact. It also proves the FT8 mode is very popular because so many people are listening and volunteering their signal reports. The reporting feature of WSJTX is turned off by default, but I would encourage everyone to enable it to help others with their reports.

My 25 watt compromised antenna signal also made it to Hawaii, and Bermuda. I covered the East coast of North America, Florida, Southern California and various places in between.

If you’re interested in long distant contacts using low power or have a compromised antenna system like I do, the FT8 mode might be for you.  It’s not really a mode for any kind of ragchew but it is great for very fast QSO exchanges so it will likely be wildly popular for Field Day and contesting.

I found several YouTube videos talking about FT8 and how to setup WSJTX but none were to the point and did not contain the level of detail I wanted to share.  Check out the links below and try FT8 yourself. It works extremely well once you get the hang of it.

~ 73, Jeremy VE7TMY


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