What does FT8 stand for?
Created by K1JT and Steve Franke, K9AN, FT8 stands for “Franke-Taylor design, 8-FSK modulation.” WSJT-X is a computer program used for weak-signal radio communication between hams. Note that this says weak signal and not necessarily low power.
What is the FT8 digital mode?
But the computer processing power grew up, and finally, the hero of our article appeared — the digital mode FT8. The name FT8 stands for Franke and Taylor, 8-FSK modulation. Professor Steven Franke and astrophysicist and Nobel laureate Joseph Taylor, have created a fascinating and efficient protocol for data transfer.
What is included in the FT8 modulation?
#Modulation includes one additional tone used for synchronization 3 Conventional Dial Frequencies for FT8, JT65, JT9 and WSPR Band (m) Frequencies (MHz)
What are the technical requirements for FT8?
• FT8 requires a program called WSJT-X or JTDX for the encoding and decoding of FT8 signals. • FT8 uses 15 second TX/RX intervals. • FT8 requires a connection between the radio and the computer (usually a USB connection) in order for the program to control the radio. Always use low power (20-40W) to avoid unnecessary interference to other hams.
What type of modulation does FT8 use?
8-GFSK modulationFT8 uses 8-GFSK modulation, includes forward error correction (FEC), and has an effective data rate of 5 words per minute. FT8 transmissions can be decoded at S/N down to -21dB (very weak signal).
What is FT8 communication?
FT8 is one of the many digital modes often referred to as sound card modes (SCM) because they utilize a computer's sound card to bring in audio from your radio to be processed by software to decode the information embedded in the signal.
What is the difference between FT8 and FT4?
FT8 messages are transmitted using eight-tone continuous-phase frequency shift keying (CPFSK). Each transmitted tone or channel symbol conveys three bits. FT4 modulation uses four-tone CPFSK at approximately 23.4 baud, with tones separated by the baud rate so each channel symbol conveys only two message bits.
What frequencies are used for FT8?
Frequencies for digital modesBandFT4FT86m50.318050.3130 & 50.32304m144.15070.10002m144.17470cm432.17413 more rows
Is FT8 killing ham radio?
So, will FT8 kill ham radio as some have posed? True, it is mostly automated. True, it reduces the skill required to make DX contacts. True, it removes conversation from the QSO the same as is true of most DX chasing contacts on any mode.
Do you need Internet for FT8?
– A Question of Timing. However the criticism of FT8 requiring an Internet connection is a bit different. Most weak signal modes require synchronization of computer clocks to a time standard. Typically, this is done over the Internet.
How do I set up my FT8?
4:0622:53Get Started with FT8 - An Introduction for Beginners | WSJT-X Ham RadioYouTubeStart of suggested clipEnd of suggested clipSo the easiest way to do that is to download. A program so i use nettime. Timesynctool.com here it'sMoreSo the easiest way to do that is to download. A program so i use nettime. Timesynctool.com here it's free and if i actually open it up i can show you what it looks.
How do I decode my FT8?
2:3611:20Decoding FT8 with a RTL-SDR (Software defined Radio) - YouTubeYouTubeStart of suggested clipEnd of suggested clipThe next thing that we're going to need is a WS JT dash X. So this program if you're not familiarMoreThe next thing that we're going to need is a WS JT dash X. So this program if you're not familiar with it is the the main software for decoding ft8.
How long has FT8 been around?
FT8 was introduced in July 2017 with version 1.8 of the software package WSJT-X [1, 2]. It quickly gained world-wide popularity, by some measures soon accounting for a large fraction of all ham radio activity on the high frequency (HF) bands [3].
How do you operate FT8?
With FT8, you're restricted to very small messages, with a limit of 13 characters per message. Each message of up to 13 characters takes 13 seconds to send. There are 4 slots per minute, and you transmit for one 15 second block, then listen for replies for 15 seconds, and transmit again for 15 seconds.
Is FT8 upper or lower sideband?
When we think of "Band," we're usually talking about, say, the 40M band, or, at least, the cw, data or voice portions of it. But FT8 is an extremely narrowband mode, around 50 Hz wide. In the case of 40M, you set your radio to upper sideband (yes, upper, even on 40M and 80M) and tune it to 7074 kHz.
Can technicians use FT8?
In addition to SSB on 10M, Techs can also work digital modes including RTTY, PSK, and FT8.
History
Of course, before the mass appearance of personal computers in homes, probably no radio amateurs were thinking about transmitting and decoding digital data. Digital modes have been gaining popularity since around the 90s.
Bit encoding
Consider a practical example — the transmission of the phrase CQ DL1ABC JO62. Here CQ is the calling code, DL1ABC is a callsign, JO62 is the grid-locator.
Conclusion
As we can see, FT8 is quite an interesting protocol. It’s a really smart combination of bit optimization, mathematics and usability. All this, combined together, made FT8 so popular. The WSJT-X sources are written in Fortran, and understanding them is not so simple.
What is FT8 mode?
FT8 is one of the many digital modes often referred to as sound card modes (SCM) because they utilize a computer’s sound card to bring in audio from your radio to be processed by software to decode the information embedded in the signal.
What is FT8 keying?
FT8 is one of a group of Multiple Frequency-Shift Keying (MFSK) modes that include JT9, JT65 and MSK144 created by Joe Taylor, K1JT and co-developers.
What is a HF transceiver?
An audio interface, a way to get receive audio from the radio into a computer and audio output of the computer into the radio, typically a sound card interface. A computer capable of running the FT8 software and time synchronization. FT8 software.
What is the best software for FT8?
WSJT-X is the most popular software for FT8. This great program is not only free but versions are available for Windows-based PCs and Macintosh OS, Linux (with pre-compiled Debian, Fedora and Raspbian distros). For details on installing and configuring the software, follow the online WSJT-X User Guide. Do not ignore the information on making sure your computer’s time is synchronized as this is vital to making contacts! After you install the software, you may also need to configure your radio’s settings.
Can you use a FT8 transceiver?
Radios. Although you can operate FT8 with older transceivers, the best experience will come by using a transceiver capable of both computer control and dedicated data mode. Fortunately, most modern radios have both of these. The extra feature that many of today’s radios have is a built-in sound card, eliminating the need for ...
How are FT8 messages transmitted?
FT8 messages are transmitted using 8-tone continuous-phasefrequency shift keying (CPFSK). Each transmitted tone or channel symbol conveys three bits. The sequence of 174 codeword bits is mapped onto a sequence of 174/3 = 58 channel symbols an, with n running from 0 to 57. The value of each symbol corresponds to a tone index in the range 0 to 7. Groups of three consecutive message bits are mapped to channel symbols using a Gray code defi ned by columns 1 and 2 of Table 3. This mapping ensures that bit triads associated with adjacent tones differ in only one bit position, thereby improving decoding performance on channels where Doppler spread is comparable to the tone separation.
What is FT4 radio?
FT4 and FT8 are digital protocols designed for rapid and accuratecommunication between amateur radio stations, particularly in weak-signal conditions. Information exchanged in a minimal two-station contact typically consists of call signs, four-character Maidenhead locators, signal reports, and acknowledgments. Special message formats support a few popular radio contests, and arbitrary text can also be conveyed, though only in small quantities. FT8 was introduced in July 2017 with version 1.8 of the software package WSJT-X [1, 2]. It quickly gained world-wide popularity, by some measures soon accounting for a large fraction of all ham radio activity on the high frequency (HF) bands [3]. FT4, a similar but faster protocol designed especially for radio contests, was introduced two years later in WSJT-X version 2.1.
How many bits are in FT4?
FT4 and FT8 transmissions always convey exactly 77 bits ofuser information. Mappings between human-readable messages and the underlying information bits depend on designed-for-the-purpose compression techniques known as source encoding. The basic aim is to give the 77-bit information payload maximum utility for conveying the information necessary for basic station-to-station contacts. To facilitate efficient message compression for a range of