  In this paper we discuss the latest developments of the STRIP instrument of
the "Large Scale Polarization Explorer" (LSPE) experiment. LSPE is a novel
project that combines ground-based (STRIP) and balloon-borne (SWIPE)
polarization measurements of the microwave sky on large angular scales to
attempt a detection of the "B-modes" of the Cosmic Microwave Background
polarization. STRIP will observe approximately 25% of the Northern sky from the
"Observatorio del Teide" in Tenerife, using an array of forty-nine coherent
polarimeters at 43 GHz, coupled to a 1.5 m fully rotating crossed-Dragone
telescope. A second frequency channel with six-elements at 95 GHz will be
exploited as an atmospheric monitor. At present, most of the hardware of the
STRIP instrument has been developed and tested at sub-system level.
System-level characterization, starting in July 2018, will lead STRIP to be
shipped and installed at the observation site within the end of the year. The
on-site verification and calibration of the whole instrument will prepare STRIP
for a 2-years campaign for the observation of the CMB polarization.
