QRZ Logbook

Wednesday, June 10, 2015

Having a blast on Digital

ICOM 706 with Signalink USB for Digital
When I went to the Dayton Hamvention last month, one of the goals I set for myself was to try a new mode of communication. All my time as a ham (with the exception of APRS a few years ago) the majority has been on voice. I've dabbled in CW and PSK31 but typically on other people's equipment, and they were the operators.

I've not been able to do much in the last few years on other modes. The last 3 years I haven't had an HF antenna because we had hail damage to the roof from a thunderstorm a few months prior and when it came time to replace the roof I took the G5RV antenna down, and never put it back up. I wasn't impressed with this particular G5RV I had anyways. I've owned them before and had good success, but this particular one has been trouble. I couldn't get a good signal on 10 meters, and several of the bands were "tunable" but I wasn't getting out to places I should have been able to reach. I figured I would get a new dipole up SOMEDAY...

Last February I finally got a dipole. 20 meter double bazooka to be exact. I've heard mixed reviews but decided to try it out and see how good/bad it was. Well, I finally got it up after a few days but it wasn't in the most optimal spot. It was barely 15 feet above the ground and was hooked up to my 6m dipole's support wire, which caused it to sag. To add insult to injury, my luck on 20 meters was no where to be found. I figured I'd wasted my money.

Fast forward to last month, when Dayton rolled around. I invested in an off-center fed (OCF) Windom (often referred to as a "Carolina Windom") that covers 80 meters through 6 meters and also invest in a Signalink USB sound card. The Signalink connects between the computer and the radio and converts text to digital encoded signals that are then sent to the transceiver and out onto the airwaves. It is then picked up by the receiving station, to then decode the message and convert it back to readable text. Sort of like an ultra-slow-speed modem. The Signalink is simply an external sound card, but rather than try to rig up cables from your computer to the radio, the Signalink takes the leg work out of it, and is pretty much universal (given you use the same radio) to any computer.

About a week after I returned from Dayton, I put together the Signalink. All I had to do was open the case and rig up the jumper wires on the circuit board, which took about 10 minutes. Once I got it set up I then installed the drivers onto the computer, which took about 20 minutes due to the computer being an XP artifact. I installed DigiPan for use on PSK31 since it was highly recommended (and freeware) and after rebooting, and some trial and error I was able to get the computer to make my ICOM 706 transmit. I tuned up the double bazooka dipole and listened on 14.07015 for any incoming signals. Almost immediately my screen lit up with activity. 

DigiPan screenshot. "Waterfall" of signals at bottom.
The bottom of the screen shows a "waterfall" that is a visual representation of the signals coming in to the radio on that frequency. Imagine if you were to key up and use your voice on 14.07015 (and just so you know, you're not supposed to use voice on that frequency, only digital or morse code) your signal would take up the entire swath of the "waterfall" that's on the screen. With PSK31, several conversations (QSOs) can be conducted at the exact same time, and all you have to do is move your mouse pointer to the line on the waterfall that you want to look at, and the program will start to show you that specific conversation in a separate pane.

I began setting up my "macros" or pre-set messages, with my call, location, grid square, and other useful information. After a few minutes of hammering out my messages, I looked on the screen and found a station that I wanted to try contacting since their signal was pretty strong on my waterfall.One nice feature about the DigiPan is that when a CQ is called, it gets highlighted on the pane that shows all the detected QSO's going on, so that you can select the conversation you want to try and get involved with.

I replied to a CQ made by N5SLY in Sherman, TX. I wasn't sure if I should be jumping in to things rather quickly. I have used PSK31 before, at Field Day events and at a friend's house, but this was my first true test of communicating with my own equipment and I wondered if I was entering the wrong protocols, verbiage, information, etc. Was I going to get chewed out for typing out the wrong information? Was I typing fast enough? As I entered the deep end of the pool, I had second thoughts, but they were quickly removed after Leland replied back with a very nice QSO. 

Over the next 90 minutes I managed to get 4 other QSO's in the log books and found out quickly that the old paper log book is going the way of the dodo. Most everyone I was talking with, or seeing on PSK31 was using some means of electronic QSO confirming that didn't involve QSL cards. Call me old-fashioned, but the thrill of getting a postcard in the mail from another city, state, country, or continent makes me happier than something that appears on a computer screen I can print out anytime. Yes, it's less expensive, but the act of getting something physical in the mail is something I always preferred.

Over the next 3 weeks, I have managed to put together about 70 QSO's off and on when I have time for PSK31 including 25 countries. I then decided to up the ante and try PSK63. Basically PSK31 at double the speed, but with more susceptibility for errors. I managed to make 2 contacts so far, but it doesn't seem to have the allure of it's slower counterpart.

As I was exploring the capabilities of my Signalink I started studying up on JT65. My friend Jim was encouraging me to get in on it but I had never heard of it until recently. Basically, you take the fewest characters on the slowest baud rate imaginable and send out your JT65 signal in synch with everyone else. The transmission starts at the top of every minute and lasts for about 50 seconds. There's a 10 second pause to allow for the software to decode the signal. Then, you spend the next minute in "Receive" mode, listening and decoding any incoming signals. If everything goes as planned, you can have a successful QSO in 7-8 minutes.

JT65-HF screenshot
What's amazing is that, like PSK31, it takes up little bandwidth, can decipher several signals at once, and can even break each signal down with their signal strength in to your radio. The recommended software is JT65-HF and like DigiPan is free to use.

The transmissions are extremely brief, yet the QSO's are long. Twitter, for example, limits you to 140 characters per "tweet". In freeform (where you type whatever you want), you're limited to 13 characters. That's "thirteen". As is, after twelve, before fourteen. Pretty much everything else is pre-formed based on the buttons you select as the QSO goes along. 

You do not send the standard signal report. There's no"5/9/9" here. The signal report is based off the software's reception of your signal from the radio, measured in decibels, or dB. -.01dB is the loudest signal, with about a -24dB being the weakest copyable signal. I was able to copy Russia with a -22 dB signal and the Czech Republic with a -21dB. The weakest I've been heard is -17dB.

It takes 50 seconds to send these few characters and the other information used by the software out. And you thought 14.4 modems were slow!

And if you want to know what JT65 sounds like, tune in to 14.07615 and listen at the top of every minute. It's almost like WWV. You hear a lot of tones at the start of the next minute, which continues for 50 seconds, then a silence for 10 seconds before the cycle restarts. The tones sounds like an ice cream truck with it's music on dying AA batteries, or if the Beatles tried to play Helter Skelter through a calliope. It's eerie but funny at the same time.

My first JT65 attempt wasn't a success. For 20 minutes I called CQ and got no responses, then tried to answer some CQ's with the same lack of success. I re-arranged my Double Bazooka antenna away from the side of the house and higher up. Then this past Friday night I decided to try again. I went to the JT65 frequency on 20 meters and listened for a few minutes. I saw a DX call appear on my screen and decided, "what the hell" and called to the station. It was ZL3HAM. And they answered me back! I thought it couldn't possibly be the country I thought it was, but I then looked him up in QRZ and lo and behold, it was indeed NEW ZEALAND! My first JT65 contact is on the opposite side of the globe!!!

How I visualize at JT65 transmission
Already in less than 4 days, I've racked up 14 QSO's with off-and-on time on the radio. In fact, 9 of them were done while I typed out this post! It's definitely a good use of time while transmitting a message.

So, if you're in the market for a new adventure in ham radio, why not give PSK31 and JT65 a try? Invest in a Signalink USB and get started right away. PSK31/63 and JT65 are just the beginning. Perhaps SSTV or some other mode is in my future?

As for the 80-6m Windom, I'm planning on putting it up within the next two weeks to try more bands, and hopefully get back on 10 meters. I did renew my 10-10 membership while at Dayton, so I'd better be putting it to good use, I suppose...

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