Bob,
Normally, I would agree with you, because I have replaced a DVD player because I was began to see pixillation on a number of discs when I tried to play them. In this case, however, all the discs in my DVD library are playing fine, with the sole exception of the ANTR one (Criterion Collection version). I have also tried that particular disc on other machines, and it simply refuses to load. I have to conclude that it is a bad disc and will have to pony up the money for a new one.
Tarn,
The Morse code in "Titanic" is not intelligible. They recorded me tapping out Titanic's distress call for "Ghosts of the Abyss," but my key sounded too "clean" (even though I matched Titanic's 60-Hz tone) and my "fist" is nowhere near as fast as Phillips' would have been, so Cameron came up with another recording. Whether he had someone else do it, or simulated the sound electronically, it sounds pretty good and if I remember correctly, he copied the characters I tapped out for him. I have no complaints.
The Marconi components in the ANTR set were all correct for the period, and some were virtual copies of some of the components installed in Titanic. The layout of both the apparatus and the room itself was wrong, but I can't fault the ANTR crew for that...no one knew exactly what parts of the entire apparatus were divided up between the Marconi and Silent rooms until Cameron explored the interior in 2001. The person who designed the ANTR Marconi set knew his business, there can be no doubt about that. I also suspect that all those components used in ANTR were original Marconi items. Cameron wanted to use original components for "Titanic," but the guy who has those original components in his collection did not want to turn them over to the production for safekeeping (I can't blame him for that...his collection is priceless and props take a beating). So, Cameron had an outfit in the UK reproduce all the Marconi components, which is good because we had them readily available when it came time to shoot GotA.
Of course, there's no way to answer your last question. One thought, though...Titanic's rotary spark put out a distinct musical tone. If Groves was an interested novice, I would think that he would have been taken by this unique tone, so unlike the "whispers" he would have been accustomed to hearing. Then again, it has been said that the magnetic detector had wound down. That clockwork ran a wire band past an arrangement of magnets that transformed received electromagnetic oscillations in the aerial into pulses that would vibrate the diaphragms in the headphones. The magnets in the "Maggie" would still be acted upon by the osciallations, but if the clockwork in the device was not running then the quality of the pulses that were transferred to the headphones would be greatly reduced. I'm not sure what Groves would have heard in that instance. We can speculate, but this is something that we will never know.
Parks
