Now I Understand Split
- Just when I was wishing WSJT could decode JT65 signals, BAMB, out of the clear-blue sky comes WSJT v1.1. Who saw that coming? It took a few days of tinkering, but I finally got the JT9+JT65 mode to work with my TS-590S. Now I'm able to sit back and work stations on either mode with a click of the mouse.
Although the manual describes running split operation, I didn't understand why. Well now I do and I thought I'd share my new-found understanding.
Why split? Although the radio can be set up for a high-cut receive frequency of 5000 Hz, the transmitter's bandwidth is still limited to a high-cut frequency of normally 2700 Hz. That means if you answered a JT9 CQ at 3500 Hz, the transmitted tones would be above the radio's xmt bandwidth resulting in little or no output. Joe's solution was to automatically change the radio's transmit frequency so that the transmitted tones would always fall between 1000 and 2000 Hz. Brilliant, absolutely brilliant.
So to operate 20m for example, set the radio's VFO "A" receive frequency to 14.076 MHz and set up the radio for split operation. Don't worry about the VFO "B" transmit frequency, because WSJT will automatically set that for you. Note that you must have CAT control working for split operation to work.
For example, if you set the xmt cursor at 1500 Hz, VFO "B" will automatically switch to 14.076 MHz. Or if you set the xmt cursor to 3500 HZ, VFO "B" will automatically switch to 14.078 MHz. WSJT will automatically set the transmit frequency to either 14.075, 14.076, 14.077, or 14.078 depending on where you will be transmitting.
Operating JT65 and JT9 doesn't get any easier than this.
. . . John (WA3CAS)
- N.B. None of the following should be taken as a criticism of the software or its author. It is nothing more than some observations from someone who was quite confused, even after reading the manual. This was primarily a result of having used another piece of software for a long time and being unable to re-conceptualize how the new software "worked".
I'm so enthused with the -X program....I woke up at 2:00 a.m. and could not go back to sleep, just had to go down to the shack and explore some more. I haven't had this much fun with HR in years!
On 7/5/2013 2:48 PM, JohnB wrote:
. . . John (WA3CAS)
Neither did I, coming from a few year's operating JT65-HF. As I read the docs, it appeared at first blush that split was optional, not mandatory. Nor was it clear to me, that radio interfacing for frequency adjustment was required. With JT-65HF, there was no requirement that the program control the radio...nothing more than PTT was a necessity, and even that might have been avoided with VOX, but I never tried it. 0ooops! Once it was explained to me that you couldn't operate even hamstrung (pun intended), without the freq agility the software contained, everything became quite clear.
I couldn't figure out as I moved up and down the waterfall, why the tones didn't steadily decrease or increase in frequency as I monitored them with my TS-2000 TX Monitor. They would all of a sudden jump and start up in a new place. Very confusing.
While the docs are very good. I would make a special effort to state a warming: Split operation is a requirement with this software, not an option. Failure to observe split operation may result in causing unintentional interference as you will not be transmitting anywhere near where you think you are unless by pure accident.
I would also include your example/explanation, as well as one Joe (W4) sent me, and combine both examples with the author's explanation.
The concept is NOT obvious to the uninitiated and downright foreign to anyone coming from JT65-HF.
All that said, the software is phenomenal, and great eye candy as well. What a nice job!
Many thanks for producing and making available such a fine program.