Doble earthquakes of Ml 3.0 and 3.1 occurred in Vernio and Barberino del Mugello on 26 April 2024 at 22:39:39 UTC and 22:39:58 UTC respectively (data from INGV).
The Modena station on the AM.R7231 seismograph, clearly captured the double earthquakes mostly in its EHN and EHE displacement components, where the seismograms shows the seismic phases P, S. The EHZ componet shows only the seismic phase P of M 3.1 Barberino del Mugello. The seismic signal was band-pass filtered 3.0-8.0 Hz and pole 2.
The two Mugello earthquakes occurred very close in time and it was not easy to distinguish the two signals.
From AM.R7231 seismic signal of M 3.0 Vernio earthquake, the difference of S-P phases is about 7.66s for a distance to epicenter of 0.518° (57.6 km). The origin time is T0 = 22:39:53.2 UTC. This value is comparable with the value calculated by INGV.
The 0Pmax along EHN is 420.6 nm for a Ml 3.0; This value is comparable with the value calculated by INGV.
From AM.R7231 seismic signal of M 3.1 Barberino del Mugello earthquake, the difference of S-P phases is about 9.17s for a distance to epicenter of 0.681° (75.7 km). The origin time is T0 = 22:39:58.0 UTC. This value is comparable with the value calculated by INGV.
The 0Pmax along EHN is not clear, and the Ml cannot be calculated.
Modena Seismic Observatory 
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