I had been in contact with Stuart for some weeks prior to the talk and it became quite clear early on that he is not only enthusiastic and knowledgeable about amateur digital modes he is also a generous and kind fellow as well.
We spoke at considerable length prior to the meet and covered various topics on the digital modes and antennas. Stuart (G4WCP) uses a non-resonant T2FD at his QTH in Brighton following inspiration taken from John Heys (G3BDQ), his teacher and mentor, many years ago. It probably comes as no surprise then that I picked up quite a lot of useful info about the various digital data modes, some of which I had never heard of before and I considered myself, quite wrongly, to know a fair bit about most things digi .. at least until Stuart chipped in with plenty of responses to my questions and offered various items of advice.
A couple of weeks prior to Stuart’s presentation at the Taplin Centre I was concerned by the possibility that the recent bad weather may have taken its toll on the club antenna again. As unlikely as this was given the recently improved re-installation of the doublet last year by Phil (G3MGQ) and Antony (G4CUS), I felt as though I could not leave it to chance without checking first. Fortunately, Leon (G1HSM) very kindly agreed to pay the site a visit for a visual inspection which revealed that everything looked in order and the evening was set to go ahead as planned.
It was a pleasure to meet Stuart for the first time having only communicated with him previously via email, and he certainly came well prepared with a Yaesu 817/LDG Tuner/Signalink ‘stack’, a tiny 8 inch tall HF setup which must be a dream to use in the field or while on QRP ops in a small space at home. Sadly, due to reasons beyond our control at the end of the PowerPoint presentation, and despite the best efforts of Phil (G3MGQ) and Paul (M6PWD), who quick-fixed a cable-tie to a PL coupler in order to hook up the balanced feeder, a source of EMI looked likely to blame as Stuart’s mouse sadly locked up intermittently while connected to the TV making the final hands-on demonstration a no-go.
Despite the sudden onset of EMI gremlins, Stuart persevered and managed to show us his digital mode setup on a laptop at the end of the evening but not before he gave his excellent talk and PowerPoint presentation which provided a useful look at his views on the subject in this very popular segment of amateur radio operating.
During the evening Stuart covered many digital modes including the JT’s, Opera, PSK, and one of his favourites, WSPR (Whisper) meaning “Weak Signal Propagation Reporter”. This is an ultra narrow-band digital mode occupying just 6Hz of bandwidth and features lossless compression using continuous phase 4-FSK modulation. One remarkable feature thanks to WSPR’s inherent efficiency is that it is capable of decoding signals with a S/N as low as -28 dB with 2500 Hz bandwidth making it more than adequately equipped for weak signal work. WSPR was originally written and released by Joe Taylor, K1JT in 2008 and has since become open source software (free to use and modify) and gained a strong following thanks to its efficiency in sending communications in the worst conditions possible, namely the operators call sign, 4 digit locator and dBm.
Personally speaking I used PSK for some time when I first started getting my feet wet with digital modes, and found it reasonably useful for discovering propagation information using the PSKreporter website. WSPR has a similar web based system (free registration required) which can be found at WSPR.net where stations that are connected to the Internet can send their reception reports directly to the site so that real-time propagation observations can be conducted quickly and easily, making the process of understanding weak signal propagation considerably easier.
Stuart also spoke about the controversial Winlink/Winmor system which is a method of sending email via RF. Stuart introduced this to me recently and often fires off email using HB9AK on 10.144.400 though it should be noted that the system is only legally operable by licenced amateurs should you happen to be interested in giving it a try. Winlink is a very valuable system in times of emergency allowing text communication to be sent via RF to the Internet and onward to its destination from any location on the planet where you are able to hear one of the many Winlink ‘email gateways’ such as the popular HB9AK which is located in Berne.
I have used Winlink using the free RMS Express software to send email and it does work very well indeed.
To Stuart’s credit for giving a great talk under the circumstances without a live demo, and everyone present for their assistance, I extend my thanks to all. It was an interesting evening listening to someone both passionate and knowledgeable about digital modes, and sincerely hope that at some point in the future Stuart will return to give us another insightful talk at the club.
Update: Stuart has since been in touch and is keen to operate G6HH using digi-modes from the club in the future and provide further insights into the practical side of digital mode operating. Something to look out for!
Images by Phil Parkman (G3MGQ).