My DR-891 is connected with cables purchased through DigiRig with the appropriate ferrites at both ends. I also purchase and have installed the isolator at the USB port on my laptop.
The FT-891 is set up as per the DigiRig setup manual. MENU 16-14 DATA DATA GAIN is set at 50. Transmit “HF POWER” is at 40W. I have a DX Commander Classic antenna with generous radial screen at the end of 75 feet of feedline with ferrites at the feedpoint. I haven’t had any issues with RF inside the shack.
The DigiRig USB “Speakers Properties” “Levels” tab has the Microphone disabled and the slider set for -22.1dB (about 20%).
The WSJT-X v2.7.0 “Pwr” slider is at 100%.
Everything was working great for months. WIth no changes made, it started in dropping the PTT immediately after it was keyed, after the first or second transmission in a QSO train. It would keep dropping the PTT immediately after keying for maybe up to ten transmissions, and I would lose the other operator and they would move on.
I tried backing off the CAT baud rate on the serial port and that did not help. I am really at my wits end on this. Any ideas what may be causing this?
Success!
FT-891
MENU 08-10 MODE DAT DATA PTT SELECT to RTS
WSJT-X
“Settings” → “Radio” tab → “PTT Method” box → select “RTS” radio button and in “Port:” select the “Standard COM Port” (that with the lower number assigned) as seen in Windows “Device Manager”.
Not sure why using the CAT commands through the Enhanced COM Port to operate the PTT causes it to drop immediately after keying approximately 80% of the time. Maybe there is another fix for this.
My SWR is 1.1-1.3:1 depending what band I am on, I have a tuner inline. I have not had any RF in the shack problems that I am aware of. I suppose I could fire up my Sangean WR-11 AM/FM radio that sits immediately above it and transmit in AM to see if there is an issue. But I can at least continue to operate my digital modes while I troubleshoot.
My AM/FM receiver picked up no stray RF when transmitting. My SWR is 1.1-1.3 through ought 40m to 10m. I am thinking there is an issue somewhere in the CAT control.
Now to isolate it to the faulty element? WSJT-X, DigiRig DR-891, or the FT-891?
I am assuming the DR-891 just passed along the USB CAT commands digitally to the FT-891 in the USB pass-through?
You can try bypassing Digirig and connecting radio’s USB directly to the computer to see if there is any difference. Transmitting at reducing RF power will also give you a datapoint for the troubleshooting.
I will try that… I have the new settings saved. I do run the AL C around 1 - 2 on the ALC scale. I turned the power all the way down to 5W and it had still done the same thing, dropped immediately after keying. I can’t get my AM radio to detect any RF other than the atmospheric static. The SWR on the radio reads right at the bottom, 1.1- 1.3:1 max. I put the tuner into bypass mode and ran it straight to my DX Commander Classic antenna, and I tuned it to be resonant on all bands at the center frequency with only the wide 10m band being the exception at the edges.
It may be my FT891 has developed an issue from the digital decode to the switching for PTT internally? The microphone has no issue holding the PTT signal open for long periods. So it seems isolated to the CAT section.
I will try taking the USB direct to the radio port.
Yeap. I did that (using RTS through the standard COM port) and it works 100% of the time.
Not sure if the radio has a problem in the CAT commands area for the PTT. I tried “downshifting” from 38400bps to 9600bps and CAT TOT set to 1000msec to no avail.
I do not have any other CAT software that does PTT at this time to test with. I could ask Christian if he has a way to do PTT through his 891ctrl software.
Maybe I’ll fire off a question to Yaesu USA support and see what they have to say on the subject.