FT-8 WSJT-X work decoding CW???

bobruzzo

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Well Bob did you get it all sorted by now. I see you still blazing the trail on 20M FT8 4 hours later.
YES I was able to get an understanding of it and sat here for 5 hours making contacts! So now I am getting the hang of it....made contacts all over using 30 watts. I will try again today but use less power, maybe 15 watts. I even went on 60 meters and made a bunch of contacts there. I got a list of frequencies where FT8 is used so I checked out the freqs on 20, 40, 60 and 80 meters. Pretty strong signals here. I also downloaded "Dimension 4" to keep computer clock accurate. Now I might want to explore some other modes, probably psk32 so thats another can 'o worms to open. Thanks for your help.
 

bobruzzo

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FLDigi is designed to key your radio's transmitter and send an audio signal which your radio then transmits over the air. This works well for "sound card digital modes" like PSK31 or Olivia. It can also work with RTTY using AFSK (audio frequency shift keying). I suppose this would also work for CW transmitted as MCW (modulated continuous wave).

However, when you put most radios into CW mode, the radio is looking for on-off keying using a "send" or "PTT" command with no audio signal. When your radio transmits CW, it turns the transmitter on and off so that the carrier goes on and off. RTTY using FSK (frequency shift keying) is similar except that in addition to the "send" command, there will also be some sort of "shift" command that causes the radio to change the carrier frequency by the amount of frequency shift you are using, usually 170 Hz for amateur radio RTTY.

The problem here is that I don't think FLDigi understands how to do this on and off keying in order to modulate the carrier. As I said, it wants to key the radio and then send an audio signal which modulates the carrier. [I'm sure someone will correct me if I'm wrong.]

FLDigi can be used to decode CW and to decode RTTY and to send RTTY using AFSK. But, for sending CW or sending RTTY using FSK, you need another program like MRP40 for CW or MMTTY for RTTY.
I am looking at MMTTY. It look's like an older program, and I am reading the manual....I can't find anything about using USB cable to serial port other than using usb adapters but they might not work with 5-bit data. I am using an IC 7300 radio with a double filtered USB cable. I have already installed the drivers for USB for the 7300 and it's working fine using fldigi and wsjtx for FT8. I got that far already. But still unsure of how MMTTY works wit modern equipment. I guess I can install MMTTY and see if I can get it to receive to start.
 

toolman60

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King and Queen Virginia
mmtty should work just point mmtty to the soundcard in radio. Fldigi should decode rtty also.

I use HRD for my logging, DM780 which is part of HRD for rtty,psk. Use WSJT-X and JTAlert for my WSJT modes.

All the frequencies are already loaded in WSJT-X. After setup all you need to do is click on the band change window it should jump your radio to band an correct frequency for the mode.

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AK9R

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MMTTY works just fine for FSK RTTY with my Icom IC-7610 and IC-7300, both with CI-V through the USB cable.

MMTTY includes another program called EXTFSK that you should use when using a USB connection. AA5AU talks about it here. In fact, AA5AU has a wealth of information about RTTY on his website.
 

bobruzzo

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MMTTY works just fine for FSK RTTY with my Icom IC-7610 and IC-7300, both with CI-V through the USB cable.

MMTTY includes another program called EXTFSK that you should use when using a USB connection. AA5AU talks about it here. In fact, AA5AU has a wealth of information about RTTY on his website.
I downloaded MMTTY and EXTFSK. I cant find out how to hook up to my radio. I am using IC 7300 with USB cable (CI-V) and everything works great doing FT8 with WSJTX.......I cant make sense out of the directions....Do I set my radio to "RTTY" or "LSB"???? I set it to receive RTTY and picking up loud rtty signal on 30 meters....but not getting anything back....I need help with audio interface cause I dont know if its set right. Not sure how to use EXTFSK. This might not be rtty signal but it sounds like it...freq. is 10.100.65.....but there are no mark & space tones in the meter, just 1 mark in middle.
 

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AK9R

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Here are some suggestions for doing FSK RTTY with the IC-7300: Icom IC-7300 USB for Radio Control + FSK Keying

The radio will have to be in RTTY mode to send FSK RTTY. The basic concept is that software, such as MMTTY, tells the radio to key (PTT, SEND, etc.) and then tells the radio to do the FSK shift. But, with the 7300, you have to jump through a few hoops since everything has to be done over the single COM port that the USB connection created. The special sauce is the VSPE software that sets up another virtual COM port and EXTFSK (or EXTFSK64) which interprets the shift commands from MMTTY into toggles of the RTS line in the virtual COM port.

With WSJT-X, the software is telling the radio to key and then sending audio to the radio which the radio uses to modulate the carrier in USB mode. You can take that approach with RTTY, but you'd then be sending AFSK RTTY with the radio in USB-D mode.

Whether you do FSK RTTY or AFSK RTTY, the software has to be configured to look at the virtual microphone set up by the Icom's sound card so it can see the audio stream coming from the radio.
 

merlin

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I am still old school and use SkySweep Pro 513. It has a nice chatbox for CW, RTTY, and a few other modes.
For TX, it can key the tx, but use SSB and the AFSK to audio.
Problem is finding it today and much less registering it or it is crippled to CW decode only and input from WAV file.
 

mm

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The only good decoder of morse/cw is the human brain, everything else fails.

With thousands of hams sending with hundreds of different styles of keys resulting in thousands of different on air fist styles there is no decoder that successfully decodes cw.

Just practice using your ears, I have taught a 11 year old hams son and the 50 year old father cw.

He was a codeless extra and the son showed interest in cw. The father was not happy with ssb/phone and digi modes and he wanted to work the weak dx on cw that I always talked about and there are zero decoders aside from the human brain that work for over the air cw so he spent the time and is now at 20 wpm, he is also deaf on one side but he did it, the son is at 10wpm.
 
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