locked FT8 Questions #NewUser #FT8


Richard Berry
 

Been trying FT8 for a while now and posted questions on the 'digitalradio' forum but got no responses, so will try here:  

1) Running FT-8, when I double-click on a station calling CQ, WSJT-X frequently starts transmitting immediately instead of waiting for the next transmit window.  Is this normal?  Is it because there's still enough time left for a possible decode on the receiving side?  I also notice it often takes multiple answers to a CQ to get a response.

2) How much power are folks running.  I sometimes see a very large difference between sent/received signals, especially from stations working Europe.  A post on the Flex forum said some are running 100's of watts, up to the full 1500W at times!  

3) In the Message section, what is the ~U.S.A. and !Italy etc?  Are these DXCC entities and is there any documentation on the use of "~" and "!"?  I scanned the most User Guide including FT8 and didn't see it. 

Thanks,
Dick
KF5SA


Kenneth Bandy
 

Hello, Dick.  My answers are in-line below:

 

From: WSJTX@groups.io [mailto:WSJTX@groups.io] On Behalf Of Richard Berry
Sent: Monday, August 14, 2017 9:43 AM
To: WSJTX@groups.io
Subject: [WSJTX] FT8 Questions #new #FT8

 

Been trying FT8 for a while now and posted questions on the 'digitalradio' forum but got no responses, so will try here:  

1) Running FT-8, when I double-click on a station calling CQ, WSJT-X frequently starts transmitting immediately instead of waiting for the next transmit window.  Is this normal?  Is it because there's still enough time left for a possible decode on the receiving side?  I also notice it often takes multiple answers to a CQ to get a response.  I have found the same thing.  This is probably due to the fact that FT-8 only is a 15 second cycle.  So, if you double click toward the end of the CQ-ing station's transmission, your station will appear to start transmitting immediately.  This would also answer the rest of your question, in that if your station doesn't get a chance to get a full return message out, the CQ-ing station wouldn't be able to decode it, hence he/she will send another CQ.

2) How much power are folks running.  I sometimes see a very large difference between sent/received signals, especially from stations working Europe.  A post on the Flex forum said some are running 100's of watts, up to the full 1500W at times!  With my station, I try to keep my output power to 30 watts for domestic (US) stations, but never exceeding 50 watts for DX stations.  Typically, when a station is transmitting using excessive power, it will tend to "desense" a good portion of the window, but there's not much we can do about that, I guess….

3) In the Message section, what is the ~U.S.A. and !Italy etc?  Are these DXCC entities and is there any documentation on the use of "~" and "!"?  I scanned the most User Guide including FT8 and didn't see it  These are DXCC entities, but I'm not sure what the other characters represent.

Thanks,
Dick
KF5SA

_._,_._,_

 

Hope this helped a bit.

 

73,

Ken, KJ9B


Carl Andreasen
 

1- I have noticed the same thing. I think if you click soon enough, it can be a valid transmission however I suspect it will come on not matter what, if you are in the correct 15 segment of the minute. I would not worry about it. I too have noticed it typically takes a number of transmissions to make contact. I think this is because of the human element. When you click on the other station, it is unlikely you did it soon enough to get the first transmission out on time, when he decodes you and responds, it is the same issue. Once connection is established the computer takes over and you sit back and watch the bang-bang-bang series of transmission.

2- Power is a personal thing, there are no rules pertaining to the mode. There is no reason to run QRP. Run whatever is comfortable for you, there is no wrong answer. Running very high power can make it difficult for others because the super strong signal drives down the gain (AGC) for others, but you can protect yourself from that by turning off your own AGC.

3- The program tries to identify the country and to alert you to if you have worked him on that band. I have not noticed the various symbols, most likely because I don't pay too much attention to it.

On 8/14/2017 6:42 AM, Richard Berry wrote:
Been trying FT8 for a while now and posted questions on the 'digitalradio' forum but got no responses, so will try here:  

1) Running FT-8, when I double-click on a station calling CQ, WSJT-X frequently starts transmitting immediately instead of waiting for the next transmit window.  Is this normal?  Is it because there's still enough time left for a possible decode on the receiving side?  I also notice it often takes multiple answers to a CQ to get a response.

2) How much power are folks running.  I sometimes see a very large difference between sent/received signals, especially from stations working Europe.  A post on the Flex forum said some are running 100's of watts, up to the full 1500W at times!  

3) In the Message section, what is the ~U.S.A. and !Italy etc?  Are these DXCC entities and is there any documentation on the use of "~" and "!"?  I scanned the most User Guide including FT8 and didn't see it. 

Thanks,
Dick
KF5SA

--
Warren - K7CWA
http://k7cwa.me