"Irv Finkleman" napisał w wiadomości
...
In the back of the plane there is a small bucket of soil with a ground
rod stuck in it. At each stop they check to make sure the soil is
damp enough to provide sufficient conductivity. On occasion a
little salt is added. The ground rod is connected to the frame of
the plane using an MFJ Artificial Ground to further ensure that
all is well. As well, the bucket is grounded to prevent any
possible cathodic action from interfering with the system.
:-)
Marconi added:
"By "connected to earth" I do not necessarily mean an ordinary metallic
connection as used for ordinary wire telegraphs.
The earth wire may have a condenser in series with it, or it may be
connected to what is really equivalent, a capacity area placed close to the
surface
of the ground (Fig. 4).
It is now perfectly well known that a condenser, if large enough, does not
prevent the passage of high frequency oscillations, and therefore in these
cases
the earth is for all practical purposes connected to the antennae."
So the plane is "connected to earth".
Is Marconi right?
S*
Irv VE6BP
"NM5K" wrote in message
...
On 4/10/2012 3:22 AM, Szczepan Bialek wrote:
In 1909 Marconi wrote:
http://www.nobelprize.org/nobel_priz...ni-lecture.pdf
"The necessity or utility of the earth connection has been sometimes
questioned, but in my opinion no practical system of wireless telegraphy
exists
where the instruments are not connected to earth."
It is still true?
S*
Pilots have no trouble using radios at 45,000 ft.
I've never yet seen one require a ground wire.
Chassis = the ground.
Is it true?
S*