"Mike Coslo" wrote in message
...
H. Adam Stevens, NQ5H wrote:
"Mike Coslo" wrote in message
...

Reg Edwards wrote:

"Bill Turner" wrote


The voltage at the ends of a half wave dipole can reach thousands of
volts even with relatively low power. Trees have been set on fire
with
as low as 100 watts. Be careful!


==============================
Hi Bill,

A half-wave dipole is a resonant tuned circuit.

A 40 meter dipole using 14-gauge wire has a Q of about 11.

At 100 watts there is 85 volts at the feedpoint.

The voltage between the ends of the antenna is 85 times Q which equals

956

volts.

Therefore, the voltage between one end of the antenna and ground is
only

478

volts.

And this falls to a much lower value when the end of the wire is in

contact

with anything by virtue of the very high antenna impedance of around

1500

ohms.

Furthermore, the antenna is immediately detuned when it comes into

contact

with anything and Tx power falls.

From where do you get your "thousands of volts" - the old wive's

monthly

magazines?

There are far more Californian forest fires caused by arsonists than
100
watt transmitters. Fortunately, it doesn't seem to have a bad effect on

the

quality of the wine.

Knowing that you are a wine aficionado, I would mention that there is
serious concern about the future quality of the wine. It appears that
global warming (which doesn't exist ha ha) has been on average warming
the regions of California where the wine grapes are grown. This is
causing them to ripen prematurely - at least as far as making the best
wine is concerned. Let us hope that a solution is in the works!

- mike KB3EIA -


But Rush said there's no such thing as global warming.
(Tell that to all the dead coral and melted glaciers.)
So sorry to hear about the wine. Better drink some moore quick!

Ahh, I kind of enjoy Rush, or did until he started to get redundant.
But I wouldn't take him as a science adviser! ;^)

Seriously, I would be willing to entertain the notion that global
warming is not happening. But what I need is a good explanation of of
the mechanism keeping it from happening. Certainly the oceans can sink
some CO2, but only so much.

The effect of CO2 on thermal retention in the atmosphere is not bogus,
and there are plenty of other gases that are likely a worse problem,
such as methane. Methane is hardly being addressed now.

There are possible effects that will mitigate the heat retention, but I
want to know what they are, not just that the warming effec isn't real.
To say that global warming doesn't exist is not far from saying Ohms law
is wrong.

I wish proof, not politics. unlike El Rushbo, I don't think that every
timee it snows is the disproof of it. We might check with our Canadian
friends on how their growing season has been affected.

- Mike KB3EIA -

It's real enough; literally decimated the world's coral reefs.
But the atmospheric carbon budget is still not well understood.
However the weather, being a chaotic system, probably becomes more chaotic
as more energy is added.
For an excellent discussion of chaos and the weather 1000 years ago see "The
Great Maya Droughts" by my old buddy Dick Gill.
Glaciers and permafrost are melting. Ice core data suggest the CO2 in the
atmosphere shot up with the industrial revolution and is at it's highest in
50,000 years.
I dove for NASA in 1970 at Tektite II in the Virgin Islands. I went back to
the site at St John in 1997.
The coral was much harder to find. Where I remembered reefs was sand and sea
grass.
I'm going back in January.
Over 10 years of diving in Hawaii I have watched the coral population at
Tunnels Beach, specifically, diminish dramatically.
One of my grad students is from Puerto Rico. He's noticed the coral decline
in his 20-odd years.
Just a couple of degrees dramatically moves the permafrost boundaries.
Any Alaskans here? Canuks?
How much are we at fault? Can we change anything? I think the answers are
some or a lot, yes and no.

OB Ham topic. I operated W3YRQ's (Jerre I am sorry if I got your call wrong,
it has been 34 years) KWM2 on 20 meter SSB from the Tektite II habitat.
I believe Jerre and I are still the only hams to operate on the ocean floor.
73
H., NQ5H