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Hi Fausto,
don't get me wrong - I'm in no way opposed to,
or trying to diminish Marconi's work, which was indeed revolutionary
at his time. I just find it hard to believe
that he actually received the famous three dots on MF at the time in 1901.
Thanks for the link to the TV documentary.
Around minute 28, the soundtrack lets us hear a real WOW signal, beautiful
and convincing triple knocks. But would the sound of a coherer really have
been like that?
Fortunately Edgar's LF receiver in Tasmania seems
is not much hampered by man made QRM, his nighttime noise floor seems
to be dominated primarily by natural static background.
All the best,
Markus
Sent: Saturday, August 22, 2015 7:11 PM
Subject: Re: LF: Re: Band is open to VK!
I know these documents and I know also how many detractors there have been
and there are against the work
of Guglielmo Marconi.
Now
I'm not here to say if in December
1901 Marconi succeeded
or not in his
attempt, I'm convinced of it, the fact is that a year later
he
successfully repeated the
experiment with the same
equipment, in front of numerous witnesses and people sent
by his opponents.
On
this there is no doubt.
As there is no doubt that all those who were
opposed to Marconi claiming to
be able to transmit a telegraphic signal before him,
when Marconi transmitted and receive to two or three hundred kilometers
away, they were unable to to
receive a signal to a hundred meters.
Here a documentary
made by a German broadcaster few
years ago:
This is one of the
best documentaries I have
ever seen and probably the closest to historical
truth.
@ Stefan DK7FC
It is true that
in 1901 there was the noise created by the man who today is present but, the noise generated by Mother Nature
was also at that
time.
Now I do not know what
could be the relationship between the sensitivity of Marconi receiver in the 1901 environment,
and a modern receiver with the noise of
today.
I recently tested some nickel powder Coherer for a historical events
which we are organizing for next month and I assure you that a carpenter's tack is
more sensitive :-)
73, Fausto
----- Original Message -----
Sent: Saturday, August 22, 2015 6:07
PM
Subject: Re: LF: Re: Band is open to
VK!
Hi Fausto,
LF,
>> do
not forget that in 1901 Guglielmo Marconi received a signal across the Atlantic at a
frequency around 500 kHz
...did he really? I think
there is some doubt around this story. With a coherer, it would be very hard
to prove the difference between receiving a signal consisting of
just three dots, and false triggering by random statics. Considering a
situation where a success was badly needed, the reception may
well have been the result of wishful thinking.
Today
we'd simply say "show us the screenshot" ;-)
Best 73,
Markus
Sent: Friday, August 21, 2015 9:59 PM
Subject: Re: LF: Re: Band is open to VK!
:-)) I have a 8 motor drone but can fly
only 20 minutes with one Kg payload.
A kite or baloon is better.
Seriously
speaking, the difficulties are
very big, as
rightly says Stefan 160 meters band, has a very
different behavior but, do not forget that in 1901 Guglielmo Marconi received a signal across the Atlantic at a
frequency around 500 kHz
and with a receiver that
in comparison with those of
today was a
tack. Ok were "only" 3500 Km.
Today what are we doing more
with our ultramodern equipment?
Today we have SDR, filters,
DSP, noise reducer, Marconi at
Signal Hill had a drop of mercury.
Today obtain
a considerable power is
relatively easy and inexpensive,
114 years ago there were only Ruhmkorff coils then, how much power
was actually radiated
no one ever taken the trouble
to measure it.
But as they did then my compatriot to get those great results: trying, trying and trying again trying to
improve something every day.
The important thing is to think that nothing is
impossible, maybe
improbable but
not impossible.
Tonight I bored with the
history of telegraphy...:-)
73, Fausto IK4NMF
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