Malahit DSP2 hums and freezes every 20 seconds

Only in FT8 mode and about every 20 seconds Malahit DSP2 stops for a second or so and emits a loud buzzing sound. And there is a reason for that.

It is not a fault of the receiver but the way of carrying a block of callsigns with related data from the receiver memory to the screen. Then you will notice that after the buzzing and blocking, a number of logs appear on the screen.

Set accurate date and time

Long press the lower left RADIO button and you are presented with this menu where, with the volume knob, you can change the data there. Turning the knob will scroll back and forth through the calendar, and pressing on the same knob will change the field (from days to month, year, time, etc.). Click on SET TIME to confirm.

However, I have noticed that the clock is not accurate, it goes on. And this is a problem in the FT8 mode where absolute clock accuracy is required.

Warning. If you forget to disable the FT8 button, the buzzing will continue on all radio listening frequencies.

FT8 is always transmitted in USB mode, regardless of the operating frequency. 

CALFT8 soft key

Press and hold the CAL FT8 function button at the start of the FT8 transmission cycle. This will synchronize the clock to the nearest minute, allowing the decoder to function correctly.

Note that the radio’s clock might be set accurately, but it could also be off by 15, 30, or 45 seconds. This is because FT8 cycles begin every 15 seconds, and it’s not immediately clear which period aligns with the radio’s clock at zero seconds.

FT8 (Franke-Taylor 8) is a digital transmission mode primarily used in amateur radio communications, designed to facilitate long-distance communication with very weak signals. It was developed by Joe Taylor (K1JT) and Steve Franke (K9AN) as part of the WSJT-X software suite, which is widely used by amateur radio operators.

Key features of FT8 include:

• Low-power efficiency: FT8 is optimized to work with extremely weak signals, often below the noise level, making it ideal for challenging conditions and long-distance (DX) contacts.
• Fast transmission cycles: Each transmission and reception cycle lasts about 15 seconds, making it faster than other digital modes like JT65.
• Narrow bandwidth: FT8 occupies a very narrow bandwidth of around 50 Hz, allowing efficient use of radio spectrum.
• Time synchronization: FT8 requires precise system clock synchronization, as transmissions and receptions must be closely aligned in time.

FT8 is especially popular among amateur radio operators who aim to make long-distance contacts under poor propagation conditions or with less efficient antennas.