Martello
In the S713 there are 60 rows, each with a duplexer and receiver but the transmitter power is obtained from a power source common to all. The transmitter is a substantial equipment housed in a separate vehicle and coupled to the antenna by waveguide.
By comparison, the S723 has 40 dipole rows, again each with a duplexer and receiver, but each row now has a locally mounted transistor transmitter, all 40 of which are fed coherently from a common r.f. source.
In both cases, the planar array is built up of detach-able 'antenna modules' which are accurately located in position by jigged fixings on the supporting spine. For transportation, the modules are removed from the spine and carried on a separate vehicle, but the detailed arrangements differ between S713 and S723 because of the difference in module size. S713 has 12 modules, each with 5 rows of dipoles; the modules are 20 feet in length and 3 feet wide. S723 has 4 modules, each of 10 rows, but they are 40 feet long and 6 feet wide. Power assistance for handling is built into the deployment system in both cases.
