Hi Jim,

N2EY wrote:
I think there's a problem with using a code that is not publicly available. ID
is not enough; if the message cannot be read by a suitably-equipped monitoring
station (read: FCC) what you have is a form of encryption.

Amateurs are not allowed to intentionally encrypt or otherwise conceal
transmission meaning or content, with one exception: remote control commands.
So the "turn off" command would be OK to encrypt, but not the data coming from
the remote sensors.

I see your point. How about this, though:

97.217:

"Telemetry transmitted by an amateur station on or within 50 km of the
Earth's surface is not considered to be codes or ciphers intended to
obscure the meaning of communications."

97.3(45):
"Telemetry. A one-way transmission of measurements at a distance from
the measuring instrument."

Also, 97.309(b) indicates that unspecified codes can be used so long as
the purpose is not to obscure the meaning of a communication.

Thanks for your input,

-Leo

--
Leo Szumel | ECE Graduate Student, UC Davis | KD5SZT
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