On the recalbox machine when I press F4 and ALT+F3 I see this:
--- 192.168.1.100 ping statistics ---
1 packets transmitted, 0 packets received, 100% packet loss
PING 192.168.1.100 (192.168.0.100): 56 data bytes
--- 192.168.1.100 ping statistics ---
1 packets transmitted, 0 packets received, 100% packet loss
PING 192.168.1.100 (192.168.0.100): 56 data bytes .....
So, I changed the IP address of my PC (from which I try to SSH to recalbox) to 192.168.1.100 (it was 192.168.1.2) and SSH worked.
SSH seem to work only if the IP of the SSH client machine is 192.168.1.100.