| 摘要 |
<p>An apparatus for locating obscured conduits (28), such as buried cables, employs a novel signal processing technique to increase the sensitivity of the apparatus, particularly in congested areas. The cable locating apparatus (10) is similar to prior art dual-peak detection devices which compare signals from two parallel induction coils (12, 14), but a phase shift is introduced into one of the signals prior to the comparison. This phase shift serves to minimize the effects of said minima in the response curve of prior art dual-peak devices. This effect is enhanced by adding a gain mismatch to the two detected signals. The locator (10) preferably operates with analog signals to reduce expense.</p> |
