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Frequencies 3.578 MHz,14.078 MHz,18.104 MHz,21.078 MHz,24.922 MHz,28.078 MHz,50.318 MHz,1.842 MHz,7.078 MHz,10.13 MHz,27.245 MHz
Frequency Range 1.842 MHz - 50.318 MHz
Mode USB
Modulation GFSK
Emission Designator
Bandwidth 50 Hz
Location Worldwide
Short Description JS8Call is an extremely-weak-signal amateur radio communication mode based on FT8. It allows FT8 to be used for conversations and message relaying.
I/Q Raw Recording
Audio Sample

JS8Call (JS8) is an amateur radio QSO communication mode based on FT8. It is popular among amateur radio operators for its ability to send and receive messages despite challenging propagation conditions, high noise environments, low power operations (QRPIn amateur radio, QRP operation refers to transmitting at reduced power while attempting to maximize one's effective range.), or even compromised antennas.

JS8Call turns FT8 into a "chat" mode, allowing stations to send longer messages "keyboard-to-keyboard." JS8Call can be thought of like a very weak-signal radio broadcast form of 'e-mail' (though it is not e-mail), where operators can check their message inbox and reply later. Messages can also be sent out to be relayed through other operators to reach a recipient operator. JS8Call conversations can also be had in real-time.

JS8Call was created by Jordan Sherer (KN4CRD) and first released January 04, 2019. Later releases of JS8Call added more features to the mode, such as higher-speed transmissions.


"From version . 0.5.x the default calling frequencies set up in JS8Call are listed below, but please note these are not set in stone and can easily be changed in your settings, or you can simply manually retune your radio to another frequency." JS8Call is designed as an HFHigh Frequency (3-30 MHz) mode, but (as with any amateur radio mode) can also be used on VHFVery High Frequency (30-300 MHz)/UHFUltra High Frequency (300-3000 MHz) if desired.

Common Frequencies for FT8 & JS8Call
Band Frequencies (MHzMegaHertz (MHz) 10^6 Hz) IARU Region
FT8 JS8Call
160m 1.840 1.842 All
80m 3.573 3.578 All
60m 5.357
40m 7.056 Region 1
7.074 7.078 All
30m 10.132 10.130 Region 1
10.136 All
20m 14.071
14.074 14.078 All
14.090 Region 1
17m 18.100 18.104 All
15m 21.074 21.078 All
12m 24.915 24.922 All
11m 27.245 All
10m 28.074 28.078 All
6m 50.310
50.313 50.318 All
50.323 50.328 All / Intercontinental DX
4m 70.100 Region 1
2m 144.174 All
1.25m 222.065
70cm 432.065

Grayed-out cells are commonly-used frequencies which are not included in the default program settings of JS8Call or WSJT-X (FT8). Frequencies for JS8Call and FT8 are adjustable by the user. "Conventions may change with time or by user preference."

(Sources: WSJT-X 2.1.0 Program default settings, DXZone, WSJT-X Documentation, JS8Call Documentation)

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