Does this ELT require an aircraft power source?
Per the supplier: No, an aircraft power source is not necessary.
What type of wire is recommended for the remote switch assembly installation.
The manufacture recommends an eight conductor wire like our part number 11-09782.
What are the requirements for testing the ELT in the US? Can it be accomplished by an A&P without special tools?
The FAA still requires transponder and ELT checks every 2 years. The E.L.T. 406 with GPS does have a quick self test feature making it easy to check without specialized tools.
Is this certified by the FAA or any regulatory body?
All ELT's must have a TSO Approval. So, yes the E.L.T. is certified by the FAA.
Post Crash, Can this unit be detached from aircraft and used with a portable antenna? Is the USA Unit still acceptable when I fly my US registered experimental certified aircraft in Canada or Mexico?
Per the manual, this unit does not list a compatible portable antenna. This ELT supports an aircraft mounted antenna.
Is the E.L.T. 406 with GPS a multiple frequency ELT, i.e., does it transmit on 121.5/243.0, in addition to 406?
The E.L.T. GPS is not equipped with a 121.5/243 MHz transmitter. This broadcast on the 406.037 MHz frequency.