IARU Monitoring System (IARUMS) Region 1 newsletter reports during March, likely as a consequence of the current military situation, they noticed an increase of transmissions in unknown modes in HF amateur radio bands
In many cases, their most probably function was to act as jammers (signals intentionally transmitted over other transmissions in order to disrupt or nullify their reception).
We also received on several occasions a signal whose possible function, given its behaviour (transmission of short but powerful bursts jumping in an organised and repetitive way along the radio spectrum), could be to act as an ionosonde (radar used to examine the ionosphere in order to determine the optimum frequency for the transmission of signals in HF bands).
Also, military modes that we had not observed for long time, such as the Russian digital mode T-230-1A, also known as “Mahovik” were copied.
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