Word: bolted
(lookup in dictionary)
(lookup stats)
Dates: during 1970-1979
Sort By: most recent first
(reverse)
Magnetic Imprint. The first expert to explain the report in the crowded Sirica courtroom was Richard H. Bolt, chairman of Bolt Beranek & Newman Inc., a Massachusetts firm employing acoustics experts. Tall, slender and professorial in manner, he ticked off his credentials, including long service as a physics professor at both M.I.T. and the University of Illinois. He noted that the panel had first assembled last Nov. 17 in Washington...
Picking up a pointer, Bolt explained a large chart that presented the panel's findings in graphic form. A principal technique used in arriving at their conclusions, he noted, was to develop the tape "in a sense that you develop a picture." A fluid containing magnetically sensitized particles was rubbed over the tape. The particles arranged themselves in conformity to magnetic imprints previously induced on the tape by electronic signals in the original recording and erasing processes. Thus the imprints could be seen with the naked eye and photographed. Bolt also noted that the signals had been analyzed by oscilloscope...
...Signature. Speaking animatedly and in a high-pitched voice, Bolt explained the rudiments of a tape recorder's operation. When the "record" and "start" buttons are pushed, the tape rolls past two "heads" containing tiny electromagnets. The first, the erase head, eliminates most previous signals on the tape. The second, the record head, implants new signals. On the Uher, the two heads are "rigidly fixed" at 28.6 mm. apart. When the erase head is released on the Uher (but not on all recorders) it leaves a minute but discernible four-line "signature" on the tape. This mark is distinctive...
...which the buzz did not appear. Although undetectable by an untrained ear, they found in each of the windows "a fragment of speechlike sound lasting less than one second." These sections apparently were missed by the erase head in the multiple manipulations of whoever tampered with the tape. Bolt explained that the assumption that speech underlies the entire buzz is basically "a statistical argument." There are only three breaks in the hum?and speech fragments appear in each. But the panelists say there is no hope of ever recovering the original conversation...
...Veniste tried to get one of the technicians to declare flatly that the erasure was "deliberate." Although the report leads to that inescapable conclusion, none of the experts would put it that bluntly. Sirica complained, "That's what I want to know." The best Ben-Veniste could get was Bolt's concession that "if it was an accident, it was an accident that was repeated five times." Several of the experts agreed that the markings on the tape were wholly "consistent" with a deliberate erasure...