Complex sentence: He used waveguides, horn antennas, dielectric lenses, various polarisers and even semiconductors at frequencies as high as 60 GHz; much of his original equipment is still in existence, now at the Bose Institute in Kolkata.
Split into simpler sentences: He used waveguides, horn antennas, dielectric lenses, various polarisers and even semiconductors at frequencies as high as 60 GHz;. Much of his original equipment is still in existence, especially at the Bose Institute in Kolkata.