100 kW coaxial cables and coaxial switches at EISCAT heating

The EISCAT heating facility uses 12 transmitters, about 100 kW each. The power coming out from the amplifiers is then fed into 12 rows of antennas using relatively large coaxial cables. Here you can see the cables and coaxial switches, which are used to route the signal into either array 1 or 2.  In order to cope with the relatively high power signals, the coaxial cables need to be low in losses (i.e., large). At these power levels, a large enough mismatch, due to e.g., water in the system, or a loose joint, can result in physical damage to the cable.  The dielectric between the center conductor and the outer conductor is warm and dry compressed air, which is continuously pumped into the system. 
Coaxial cables and coax-switches at EISCAT heating.