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Re: [Discuss-gnuradio] Transmit legit, become a ham

From: Gregory Maxwell
Subject: Re: [Discuss-gnuradio] Transmit legit, become a ham
Date: Fri, 5 Mar 2010 15:46:23 -0500

On Fri, Mar 5, 2010 at 6:22 AM, John Gilmore <address@hidden> wrote:
>> Nothing forces you to interact with other ham radio operators. You can
>> happily work in isolation communicating among your own stations if you
>> wish.
> Unless you need to do frequency coordination, which you usually do.
> Then you have to deal with the oldest, gnarliest hams around, the ones
> who 50 years ago got access to mountaintop towers and have been squatting
> on them ever since, like trolls under bridges.

Mostly echoing what Kelly said...  Operating in the DC suburbs I've
never had need to coordinate, there is always plenty of inactive space
on the 23cm band.  Though perhaps in California (where there is a lot
of 23cm activity, as I understand it) experiences may differ.  Some of
the amateur allocations overlap ISM allocations, so even the worst
spectrum dictator would have little hope of micromanaging that.

I suppose its a little different if you're looking to run something
like a persistent packet BBS.

> I got a ham Tech license in the 1970-80's and it was one of the more
> disappointing experiences in my life.  What a culture clash!  The ham
> fraternity was filled with people who spent all their time
> chit-chatting on their handheld radios about their personal lives, but
> who knew and cared very little about radio technology or computers.
> (Nowadays everyone has cellphones, but in those days they were the
> only ones who could communicate mobile.)

In my direct experience this has changed (Although I've only been
licensed a couple of years, I've owned a radio for a decade and seen
the decline and shift away).  Between the internet, pervasive cell
phones, SMS, and such people that simply want to chat have moved on to
mediums which better support technophobes.  Certainly they still
exist, but today in most areas the bigger problem is under utilization
of the allocations (especially the UHF/SHF ones) and the related fear
that the allocations will be taken away.

> since.  I think the hams are still doing 1200 bps FSK, while the
> unlicensed folks have evolved to 108,000,000 bps WiFi.

At lower frequencies the latest fads involve low speed very
narrow-band efficient modulations such as PSK-31, and other low speed
fancy forward error corrected protocols which operate at near the
information theoretic limit like JT65B.  At higher frequencies D-STAR
is becoming popular in some areas, and D-STAR depends on a
proprietary, patent encumbered, and trade-secret speech codec.

Of course, there are people running multimegabit and even WiFi systems
operated under part 97 (e.g. switched into ham bands, or on the
overlapping ISM segments but with the ham emission restrictions rather
than the part 15)

> There must be
> tens of thousands of hams nationwide.  There are tens of thousands of
> WiFi nodes in San Francisco alone -- and no crazy restrictions about
> not using encryption, not letting other people use your radio, etc.

There are about 700k licensees.  Who knows about how many are actually
active, or even living. I could only assume that it would be
significantly less than half.

Of course, 99.999% of your WiFi nodes are just some Apple controlled
appliances with users who even more are blissfully ignorant of how the
technology works.  It's great for facilitating communication, but the
bulk of it isn't facilitating advancement of the art of radio
engineering.   Because the technology encourages ignorant usage any
effort to build more intelligent infrastructure (meshes and such) has
to contend with the interference from those tens of thousands of nodes
with little to no hope for relief.

It's a bit bogus to compare the lack of restrictions on ISM with the
restrictions on ham radio. If your ISM radiated power is high enough
to have any real range on your uncertified equipment, you're in clear
violation of the FCC regulations.

I suppose you could argue that enforcement is much more likely in the
ham bands, and I suppose that may be true but I don't think it's fair
or accurate to say that the restrictions are worse.

The content, crypto, and usage restrictions are silly on ham radio,
especially when compared with how people are using part 15 devices. I
think the goals for spectrum management could be better achieved
through other means. But getting the rules changed would require
having new blood around to petition the FCC to change the rules.


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