Questions tagged [ft8]
For questions specific to the FT8 mode
19
questions
9
votes
2answers
3k views
Am I really receiving FT8 signals from 12,000 km away on 144 MHz?
I have been using an Ettus B200 SDR to receive FT8 transmissions in the 2-meter band (144.174 MHz) using the WSJT-X software. Signals are received using a telescopic antenna inside on a window ledge ...
0
votes
1answer
49 views
FT8 in slow motion?
Do FT8 operators typically respond to very late replies for an entire QSO? (for instance, transmitting in the 3rd slot or 5th slot after a CQ, to maintain even/odd alternation, instead of the time ...
3
votes
1answer
109 views
If WSPR can go further than FT8, why do I only see local WSPR signals?
I've been scanning through the bands using WSJT-X to pick up FT8 and WSPR. Using a VHF discone, I decode messages from nearly 10,000 km away, consistently, when listening for FT8. But when switching ...
2
votes
0answers
44 views
FT8 low-density parity check code
The FT8/FT4 communication protocols use an 83x91 generator matrix for the low-density parity check code. I am interested in MATLAB recasting of portions of these protocols. Can anyone explain to me ...
8
votes
1answer
177 views
FT8 callsign/maidenhead compression encoding
I have set myself a challenge to write a Matlab script as proof of concept to send an FT8 CQ call (not necessarily for live transmissions yet, but I may extend the project). So far I have:
Generated ...
5
votes
1answer
270 views
5
votes
3answers
559 views
Only noise, no signals whatsoever on HF
Last night there was a power outage at home. I was able to see a LOT of stations on 20M (FT8). As soon power returned, all of them disappeared. You can see in the waterfall very clearly when power ...
5
votes
3answers
860 views
Unidentified signals on FT8 frequencies
When I work in FT8 mode I often see signals like these:
I couldn't identify these signals using SigiWiki nor managed I to decode them using WSJT-X. Though these signals seem to use 15 second frames. ...
1
vote
1answer
349 views
Should I add call signs with /R suffix to the logbook?
Sometimes in FT-8 mode I receive calls like this one:
It happens 2-3 times a week.
The problems are: 1) I never could look up such call signs 2) I tried to reply, but never got answer 3) I don't ...
1
vote
1answer
70 views
How many HF (FT8/JT65/BPSK/RTTY etc) amateurs are active in Canada? [closed]
It's silent over there... USA is full of FT8 stations, in Canada you can count them on one hand and you don't even need all your fingers...
7
votes
1answer
487 views
What does CQ NM mean in FT8?
I saw someone on 20m FT8 this morning calling "CQ NM". What does NM mean in this context? The followed the NM with their call and grid as usual.
2
votes
1answer
2k views
WSJT-X V2: How to identify stations already logged?
In V1.9 of WSJT-X, there was a feature that allowed one to change the color of stations already logged. This was necessary in knowing whether or not to respond to a given CQ.
In version 2, I am ...
4
votes
2answers
977 views
What is the minimum equipment necessary to get on the air with FT8?
To the extent that FT8 is a way to bring people into the hobby or re-ignite passion among those who haven't been on the air in a while, what's the easiest way to get someone on the air with this new ...
4
votes
1answer
2k views
Can the IC-7300 be connected straight to a computer and use WSJT-X for FT8?
Do I need a separate device to use digital modes with the IC-7300 or do I just need to connect the 7300 to my computer via USB in order to use WSJT-X for FT8?
Thank you.
1
vote
1answer
170 views
Can WSJT-X's timing account for delay from RCForb?
I was using FT8 through a remote in RCForb. Reception in FT8 is spotty through the remote. I do not have an HF rig to test if the remote is the problem. So far, I think it is the delay through the ...
3
votes
1answer
359 views
How/where can I learn about ft8? [closed]
Where can I find information about the digital modes and how to get started on them? I would like a concise yet easy to understand tutorial.
4
votes
2answers
766 views
Long callsigns in WSJT-X?
During the month of May (2018) a lot of Belgian club stations can use callsigns in the format OT70xxx. (The xxx is always 3 letters, for example our club station uses OT70TRA.)
In WSJT-X it seems ...
4
votes
1answer
123 views
What does retain mean in the logging of WSJT-X 1.8.0?
If you have automatic prompt for logging on WSJT-X, at the end, you get this dialog:
What does the "Retain" checkboxes do when you check them?
9
votes
2answers
391 views
What does exclamation mark mean in FT8 CQ calls in WSJT?
For example, in this screenshot:
WSJT shows !Italy, !Serbia, !U.S.A. What does it mean?
