A quick test of a US Robotics external 56k fax modem with no phone line available.  Future testing with a second modem will confirm further functionality.

Links mentioned in the video:

AT Hayes command reference guide:
https://www.sparkfun.com/datasheets/Cellular%20Modules/AT_Commands_Reference_Guide_r0.pdf

USB Serial Adapter drivers located at:
https://www.startech.com/Cards-Adapters/Serial-Cards-Adapters/USB-to-RS232-Serial-Adapter-Cable~ICUSB232V2#dnlds

CoolTerm Serial Com Program:
http://freeware.the-meiers.org/

Serial Cable Pinouts:
http://www.bb-elec.com/Learning-Center/All-White-Papers/Serial/FAQ-RS-232-Connections-That-Work.aspx

DTE vs DCE Discussion:
http://ftp1.digi.com/support/cabling/dte_vs_dce.pdf

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