Many thanks to SRAA contributor, Dan Greenal, who shares the following recordings and notes:

Notes: With roots over 100 years old, the Tropical Radio Telegraph Company (a subsidiary of the United Fruit Company) used to operate a few radiotelephone stations in Central America during the years prior to the Internet. They often could be heard on various shortwave frequencies transmitting a repeating test message so the receiving station could tune them in. I managed to pick up 4 of their stations in the early 1970's. These recordings are from La Lima, Honduras; Managua Nicaragua; and Panama City, Panama. I have not been able to find the one from Tegucigalpa, Honduras, but maybe it will surface later.

Broadcaster: Tropical Radio Telegraph Company (point to point)

Date of recording: unknown

Starting time: unknown

Frequency: various

RX location: Ancaster, Ontario, Canada

Receiver and antenna: Hallicrafters S-52 using a longwire antenna

Mode: Single Side Band