[Milsurplus] Carbon mics, more.....

[AKLDGUY .]

Gleaned from a telecommunications history book a few years ago:

 "Radio telephone communications opened in 1927 on a 24 hour
 basis, US-UK. By 1949, there were 70 radio telephone circuits for
 all 5 continents."

 So, by 1937 it was possible for telephone subscribers to place
 calls and talk between the US and UK, and probably other more
 remote places.

 Now if Earhart's transmissions were being relayed by one of
 those circuits as a precaution for rescue, and perhaps even to
 the US, it's entirely possible for a young enthusiast to overhear
 the relay transmission even though he couldn't hear Earhart
 direct.

 Propagation dictates that those circuits were probably 13 MHz
 and up, and not all domestic receivers of the day had shortwave
 bands.

 73 de Neil ZL1ANM