Re: Utilizing DRAWS to encrypt handheld radios

Stuart Longland VK4MSL

On 22/5/20 4:38 pm, Digital Alchemy wrote:
Using encrypted radios is completely legal in the US.  the FCC rules are more based around the language of frequency and tx power.
If you're talking commercial-band stuff, then yes, encryption? Sure,
knock yourself out. Amateur bands? Well, that differs.

Here in Australia, it is permitted for emergency communications and in
EMCOMMS exercises, as well as for remote control of equipment.

I understand the FCC rules are a lot more strict on this and do not
allow EMCOMMs traffic to be encrypted.

The real question is, "what hand-held radio"? They come in all shapes
and sizes from your $2 AM set that maybe puts out 10mW and is set by a
crystal in the upper HF… right through to eye-wateringly expensive TETRA
and DMR hand-held radios which likely do their own encryption.

The former could be "encrypted"… you'd just have to interface to the PTT
(fun, because sets of that vintage often used multi-pole switches so
they could cheap out on the transistors), but would be illegal to do so
as I'm pretty sure any kind of data communications at 27.145MHz would be
a violation of the Citizen's Band Radio Service Class License (or
rather, its US equivalent). This is also the case for the more modern
UHF CB sets at 477MHz.

Amateur: again, depends on the scenario, sometimes it's legal, most of
the time it isn't, so most of us have not bothered. QSSTV does work on
the Raspberry Pi, can send files using HamDRM, and HamDRM does not care
if you're sending a photo, plain text, or a blob of data encrypted using
openssl/GnuPG/whatever crypto tool.

Anything else you can get hold of as a mere mortal… smart money would
say it's not legal to use encryption on that band.
Stuart Longland (aka Redhatter, VK4MSL)

I haven't lost my mind...'s backed up on a tape somewhere.

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