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[Ham-80211] OT??? High power 2.4 GHz rules change

Tim Gorman ab0wr at ab0wr.net
Sun May 21 18:03:02 UTC 2006


On Sunday 21 May 2006 13:13, jeff at aerodata.net wrote:
> Tim told us:
> > I am not against high power being used on SS. I *am* against it being
> >used indiscriminately.
>
> Already covered. I suggest you read the FCC rules, as your concerns are
> already addressed -> 97.313(a)An amateur station must use the minimum
> transmitter power necessary to carry out the desired communications. ).

No, not already covered. If it were already covered we wouldn't have the 
problem on the HF bands with people running amplifiers when they are not 
needed. The thing about HF is that these are narrow-band signals and lots of 
spectrum space exists so you can avoid them by turning your vfo dial. With 
just a few SS channels available that a multiplicity of users have to share, 
turning the dial is not that easy. And if you shift to a different spreading 
code then how do you find anyone to talk to?

You can pooh-pooh it all you want, it is still a fact of life.


>
> http://www.arrl.org/FandES/field/regulations/news/part97/d-305.html#313
>
> >APC should not hinder experimentation in any way.
>
> Says you. Algorithms have to be written, handshacking done. You continue
> to think hams in their basement have access to chip fabs. APC is not that
> hard to do, yet it is just another layer of complexity which in many cases
> is not even needed (like on a fixed point to point link).

And no one has answered why 100watts is needed on any SS point-to-point link. 
If you stay at 1 watt and under, you don't have to worry about the APC rule. 
Then complexity is not an issue, no algorithms have to be written, no 
handshaking has to be accomplished. 

As far as chip fabrication is concerned, I believe the first TAPR SS unit used 
a NE605 DBM mixer in the receive chain which provides a received signal 
strength indicator lead. Such a simple implementation would give you a 
perfect (No + Io) measurement with which to establish power levels. 

Unless you are going to be using off-the-shelf units that are already 
programmed for a specific purpose, e.g. 802.11 routers, you will already be 
involved in writing algorithms and handshaking for the application being run 
in your equipment. Adding such a small thing as a psuedo-802.11h setup would 
be a minimal thing. 

>
> >Yes, it might increase complexity slightly but
> > so what? Single Sideband increased complexity over AM. That didn't
> > seem to hinder its development much.
>
> Exactly! And do note that SSB was not mandated by law, and AM was not
> outlawed. Yet even though the goverment didn't force it, the development
> you cite still happened. Believe it or not Tim, when it comes to the
> goverment, less is more.

Certainly it means more power, whether it is needed or not. Listen to 3922khz 
some evening. As for the rest, I'm not sure what you mean. The complexity did 
NOT keep SSB from being developed - yet you are saying it *will* keep down 
development of Spread Spectrum. 

You seem to want to have it both ways.



> >That is
> > just another non sequitur put forth by those who just want to hang bricks
> > on
> > their transmitting chains to make up for other inadequacies in the
> > design.
>
> Do you really believe all this crap you continue to spew out? "Oh my gosh,
> oh my gosh, if we don't pass a law, Johnny Ham will put a kicker on his
> 802.11b card, and tune for maxium smoke!! We must protect the unlicensed
> part 15 users from those hams!"
>
> Cut me a break... Your chicken little tactics may play well to the WISP
> audience, but they don't amount to much in fact.

Chicken little tactics? I suggest you go look on ebay sometime to see what is 
available. 20watt bricks are readily available - even for 2.4Ghz. While they 
are certainly pricey, 50watt and up bricks are available as well. 

You would have us believe that this is NOT where things are headed when it is 
obvious that they are. If you'll just take the time to look you can find 
information on the internet about people who have added things like water 
coolers from rodded PC's to their wifi router power chips in order to run 
them at max power levels without burning them up!. 

Do you really think the rest of us are so stupid as to not be able to look 
back on history and be able to learn from it?

>
> You don't get it Tim. APC is a good idea, we do agree on that, yet I don't
> think it should be mandated by law on part 97. I think the less rules we
> have in the amateur service, the better, since that broad canvas best
> faciliates experimentation and the advancement of the state of the art.
> And guess what? It has served us well over the last 80+ years.

Using this logic why do you suppose the FCC has set a power output limit of 
1500 watts PEP in the amateur bands? Shouldn't we be expected to only use 
that power that is needed? And certainly there are times when 5,000 watts or 
eve 10,000 watts would be useful in emergency situations. Why aren't we 
allowed to use stations running commercial power levels when needed?

Would you also advocate that the 1500watt PEP limit be removed? If you are 
going to follow the same logic you espouse above, you certainly will!

>
> If anything, you have made a defacto case for implementing APC on the WISP
> industry, as 1 watt is not a magic number by any means. Hams passed a test
> so they COULD tinker with radios, the part 15 user, as far as the FCC is
> concerned, it is a black box and they are are not expected to be able to
> do path calculations.

You seem to make no distinction between a WISP and an average Part 15 user. In 
your rush to lash out you are losing the coherence in your argument. I would 
certainly expect someone doing something as a business to be able to do such 
a simple thing as a path calculation - especially if I were an investor in 
the business. As I pointed out earlier, designing a system to use maximum 
power all the time is a poor engineering practice. It causes increased system 
maintenance costs, increased initial investment costs, increased spectrum 
pollution, etc. It is *these* people that I would expect to find using the 
absolute minimum power level needed and who would be the *biggest* proponents 
of APC.


> And at the risk of beating a dead horse, this is the same ARRL that 10
> years ago asked for APC dispite the protests of TAPR, Phil Karn and
> others. Now, I am glad they saw the error of their ways, and are trying to
> correct it, however I want to point out that once again, with bandwidth by
> regulation, they are asking for unneeded regulations on amateurs. Lest I
> point out the obvious, we need to learn here from history. Ask your ARRL
> director to not support limiting bandwidth by regulation, but only by good
> amateur practice, as has been the standard since almost day one of amateur
> radio. Amateur radio operators can be trusted, and don't need to be told
> what is right and what is wrong.
>

This isn't an issue of "trust" in amateur radio operators. It is a matter of 
what the FCC needs to do to insure the spectrum is usable by everyone. That 
includes narrow-band users of the amateur bands as well as Part 15 users in 
the shared-use bands we inhabit. We agree on the bandwidth regulation 
proposal but apparently for differing reasons. I see it as a problem with the 
ARRL recommending the mixing of inherently incompatible modes and expecting 
voluntary bandplans to be effective when it is obvious that they are not 
(look at Region 1 experience and look at the ARRL's own experience in 
following its own voluntary bandplan).

tim ab0wr




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