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and power handling capability the filters are often solidly constructed

cavity resonators with an insertion loss of 1 dB and a bandwidth of

0.1% to the −20 dB points. Figure 19.4 shows the layout of a trans-

mitter/receiver sharing system.

19.10 Emergency power supplies

The installation of equipment to provide power for all the equip-

ment on a site during a failure of the public supplies has declined

in recent years. But although lengthy power failures seem to be a

thing of the past, they could recur, and electricity supplies do still

fail for short periods. To provide a complete supply for large station

necessitates a standby generator. On smaller stations batteries may be

capable of supplying the demands of the electronic equipment and

emergency ...