| 摘要 |
The transmitter is provided with separate means for the transmission of a first frequency and a second frequency. It is contained within a floatable housing. The transmitter is connected through a switch to a battery. The transmission means are comprised of a common quartz oscillator connected with frequency multipliers which are connected to drive stages and to high frequency final stages. The latter are connected to a transmission antenna which extends from the housing, as well as to a signal generator for modulating the transmitted frequencies. A problem raises when rescuing at sea as to the size and weight of the apparatus in particular when it is permanently carried by a person. A decrease of these parameters is not possible beyond a certain limit due to the capacity of the battery and the transmission output. To solve that problem without decreasing the range and duration of transmission while reducing almost by half the size of the battery as well as the power that it should deliver, a clocked control device (for example 36) is incorporated to the first (11) and to the second (13) transmission means which alternately sets in operation both means (11, 13). Thus, the operation requirements of the battery are reduced to those necessary for a single transmission device. |
