Abstract: Various systems for improving the useful signal to noise ratio of signals received on different aerials and for use when the noise comes from an external source so that the noises received by the different aerials are at least partially intercorrelated are disclosed with compensating delay newworks for making the different useful signals identical with each other, in conjunction with an assembly, which takes on any one of numerous forms, for causing those identical signals plus their respective noise signals to undergo phase and/or amplitude modifications so that the intercorrelated noises come closer to the conditions of equality of amplitude and phase opposition than the useful signals themselves. The so modified signals are then added so as to eliminate the equal amplitude phase opposed noise signals.