Sorry I'm not more specific, but I'm on a trip right now and do not have immediate access to the radio and manuals.īut you should know that the FT-991 works very well on JT-65 and JT-9.This is a photo of the kit currently used. I've examined FT-991 output with a spectrum analyzer and found the output signal purity to be just fine with ALC at 50% - no IMD death rays shooting out of the antenna connector. You will need to re-adjust levels as you move from one end of the audio pass band to to the other. A 50% setting will stabilize output power, especially if you are operating near the audio passband edges. The ALC level at the radio should read about 50%, not zero. Next, make sure the variable bandwidth control (essentially PBT) is set as wide as possible. In particular, the FSK mode settings seem to affect "Other" operation, too, at least in my firmware version. The Yaesu menus do not always behave as you would expect them to. To maximize audio bandwidth for JT-65, make sure the roofing filter selection is as wide as possible, then set the digital mode filter slopes and cutoffs as gentle and wide as possible, even though you've set their enable to "OFF". There IS a pronounced falloff at the edges of this bandwidth and the FT-991 frequency displayed is offset from the WSJT-X display unless you program the WSJT-X offset as you described. I get about 3 KHz of usable bandwidth out of the radio for this application. I run JT-65 and JT-9 on an FT-991 all the time (as well as an FTDX-3000) I guess it doesn't matter, there being no real difference between 7W or 10W in the real world. I find this strange and a little worrying, not sure if this is a feature or a fault with the rig. I also find that if I adjust the output level to set a power output of say 10W, that after a few minutes of operation the 10W has dropped to 7 or 8 and I have to increase the audio out to get it back to 10 and there is still no ALC. What I do find is this setting varies depending on the audio frequency used which is odd.
the following menu items.Ġ64 OTHER DISP (SSB) = 1500 Khz This corrects the frequency displayĠ65 OTHER SHIFT (SSB) = 1500 Khz This widens the audio bandwidthĠ71 DATA PTT SELECT = RTS I guess this depends on your rig control options, I use HRD with RTSĪs far as the ALC level adjust I just TX and adjust the audio out level until there is no ALC. To keep this post short, this is what I ended up doing and all is now well. I tried setting the menu item 062 DATA MODE to OTHERS as suggested on other postings, but the audio bandwidth was then even worse. Secondly I found there was a narrow audio bandwidth indicated by more noise on the edges of the waterfall compared to my FT-847 or FT-817. But I have had a nightmare overcoming some issues with it when working JT65, I use WSJT-X v1.6.įirstly with the FT-991 set to Data Mode I found the frequency I had to set was 1Khz higher than I expected, which was ok, except that WSJT-X likes to prevent you using JT modes in sections it thinks are reserved for WSPR, but actually I wasn't in those sections. Firstly I love the FT-991 which I recently upgraded to from my old FT-847.