US Navy personnel helping to look for missing Malaysia Air Flight MH370 are using the signal-processing and analysis package Spectrum Laboratory by Wolf Buescher, DL4YHF, to analyze recently detected 37.5 kHz “pings” that may be from the missing plane’s “black box.” Some Spectrum Laboratory screen shots as seen aboard the Australian Defense Vessel Ocean Shield were shown on TV. The US Navy personnel are guests aboard the Australian ship. VLF experimenter Warren Ziegler, K2ORS, said the software is the same package Amateur Radio experimenters used recently to detect transatlantic signals on 29 kHz.

“Wolf’s package is very first-rate software, and I know that there have been other professional uses, but this was quite an interesting one!” Ziegler said.

The software began as a simple DOS-based FFT program, but it is now a specialized audio analyzer, filter, frequency converter, hum filter, data logger and more, and it is available for download from DL4YHF’s Amateur Radio Software site.

Buescher said he was skeptical about the initial “ping” detection by one of the search vessels, but now, he says, “the spectrogram taken by the US team aboard Ocean Shield is convincing.” He said a screenshot from Australian TV clearly shows the “bip-bip-bip” ultrasonic bursts or pings, “just as they should look,” rather than a “just a wobbly carrier that comes and goes.”

“In slow-CW terms, it would be an ‘outstanding signal.’” Buescher said. “Now keeping fingers crossed that the [“black box”] batteries last a bit longer than specified. The experts say the pinger’s battery usually degrades slowly, instead of going QRT abruptly.”