He offers an alternative explanation for Amelia's inability to hear radio from Itasca: She had planned to use the DF loop antenna (rather than her belly antenna) for 3105 and 6210 receiving. He explains why the DF loop was totally unsuitable for such short wave use: Only when Earhart's plane was nearly on top of Itasca would she be able to hear their 3105 and 6210 transmissions. And that DF loop couldn't be 'nulled' at those high frequencies. Which pretty much squares with the evidence.
I think Hooven was jumping to a conclusion when he wrote:
"Before taking off on her fateful round-the-world flight Miss Earhart had announced that she did not intend to use her radio receiver for communication, that she would broadcast her position on the quarter and three quarter hour, reserving her receiver for direction-finding purposes. From this it can be concluded that her receiver was connected only to the loop antenna and that she did not realize that the loop would be substantially useless at frequencies above 1500 kc, either as a loop or as an antenna. Thus it was that she did not hear the Itasca’s signals until she was closest to Howland, at which time she finally reported hearing the signals but that she could not get a minimum."
That's not quite right. The belly antenna was connected to the receiver. You can see the lead-in wire from the belly antenna to where the receiver was located under the co-pilot's seat. Earhart's statement implies that she would only use the receiver for direction finding and would not listen for messages. We know that she did, in fact, listen for messages.
The only time Earhart heard anything on the morning of July 2nd was when she decided to try to DF on Itasca and asked them to give her a "long count" on 7500 kcs. They sent "A"s in Morse code (they had no voice capability on 7500) and she heard them. If she had been listening on the loop all along why did she hear the "A"s and not hear Itasca's voice transmission on 3105? I think she could switch back and forth between the belly antenna and the loop (otherwise, why have the belly antenna at all?). The belly antenna was missing so she heard nothing until she decided to try to DF and switched to the loop. When she didn't get a minimum she switched back to the misusing belly antenna and heard nothing. Had she stayed on the loop she would have heard Itasca's voice transmissions on 3105.
He also explains that short wave frequencies were unreliable over relatively short distances. Lower frequency 3105 would, presumably be more reliable than the higher frequency 6210. Which, in simple terms, explains why her last inflight signals were heard on 3105 and vanished when she switched to 6210.
To my mind, then it would suggest that the Electra was very, very close to Howland when she reported hearing signals from Itasca.
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Others have been of the same mind. That's why four expeditions have spent millions of dollars searching the ocean bottom near Howland. Nothing has been found.
Computer modeling of the Electra's transmitting antenna reveals a flaw in the propagation pattern. See
"The 3105 Donut" and the graph attached here.. For Itasca to hear transmissions from AE as loudly as they did, she had to be at least 150 and maybe as much as 250 miles away.