It’s been 3.5 years since I wrote this post and I’m not sure the information in it holds up anymore, as I was a very new ham when I wrote it and I was still learning. As with many things in ham radio, the obvious solution isn’t always the right one. I’d defer to Jarrad’s comment below as a good clarifier. — KK4DSD
I wasn’t having much luck making phone contacts tonight, so I tuned over to the popular JT65 frequencies and heard a lot of activity. I switched off my QRO rig and fired up the FT-817, running on battery power, as it wasn’t connected to my station power supply at the moment.
On 40 meters, I started CQing with 2.5 watts and had a station in Ohio respond immediately. He had a nice signal, -7, and came back to me with a -8 report.
I reasoned that if I was that loud on a stateside contact at 2.5 watts, I could go with much less power and conserve my battery. So I dialed the 817’s power back to its lowest setting — half a watt. I CQed again and a station from Illinois responded, giving me a -11 signal report, well within range of a copyable signal for JT65.
I CQed once again and a Quebec station 1,000 miles away came back with a -12 signal report. Again, a very good signal for this mode.
I decided to try my luck on 20 meters and see if I could score any DX. I CQed repeatedly, but never had any takers, then I noticed several VERY loud signals in the waterfall. One of the stations had a booming -3 signal and he was basically quieting the entire frequency on transmit. Then another signal came crashing in, and the weaker signals not wiped out by the -3 station, were certainly wiped out by the second loud station.
Folks, JT65 is a weak signal mode. Five watts is considered high power for JT65. I have no way of proving it, but I suspect stations are raising their power levels a good bit. One thing’s for certain, if you are full-quieting the frequency, you’re using too much power. You’re stepping on everyone else on frequency who is trying to operate in a proper manner. And by the way, check your ALC, because some of you gators are causing splatter comparable to the best death scenes from Italian horror films circa 1980.
I enjoy JT65 because it lets me make QSOs on a very small amount of power. I have a high level of success with the mode, as long as folks play nice and keep the power down to a considerate level.
And if you don’t believe me, check out the JT65 Power Calculator, one of the best tools I’ve come across concerning this mode. (Edit: It looks like the power calculator has been down for at least several days. I hope it comes back to life, as it’s a very nice tool.)
Is there even a reason to use JT65 for casual QSOs if you have higher levels of power to burn? If I had more power, I’d run PSK or RTTY, because frankly the “Russian ice cream truck” sound of JT65 isn’t THAT fun to listen to. I use it because it lets me make contacts with my low power, not because I enjoy a 6-minute macro-based QSO with no real interaction.