RadioBanter - View Single Post - What makes a Pro code test Amateur a Troglodyte?

October 14th 03, 07:10 PM

In article ,
(Hans K0HB) writes:

(Len Over 21) wrote

The ONLY way a "spark" transmitter could send anything called
communications information was by on-off keying.

Damn, Old Timer, you got it wrong again! In Boston, on Christmas Eve
of 1906, modulating a spark transmitter, Reginald Fessenden made a
holiday broadcast of a short spoken introduction, some recorded
Chistmas music, and played "Oh Holy Night" on a violin.

Obviously a "spark" transmitter was not limited to ONLY (your
emphasis) on-off keying.

Sunuvagun! Good luck on this one now.

THE FOLLOWING IS A REPEAT OF AN OPEN LETTER TO THE
CONFUSED OFFSPRING OF MOTHER BRAKOB, REPEATED
HERE FOR PUBLIC EDIFICATION -

=================================================

Dear Mother Brakob,

Your offspring is once again confused, perhaps suffering from
dittybopper dementia from spending too much time listening to
beeping or seminarian studies of official documents from Newington.

The following is a direct quote from the Special Commemorative
Issue of McGraw-Hill's "Electronics" magazine of April 17, 1980,
page 75, section titled "History before 1930." That issue is 650
pages total, was printed in celebration of 50 years of "Electronics"
magazine.

"The broadcast television that followed two decades later, would,
of course, not have been possible without proper transmitters,
receivers, modulators, demodulars, etc. --or, in other words,
without proper radio. The world had been introduced in the potential
of such a radio system as far back as 1906, when on Christmas
Eve Prof. Reginal A. Fesenden of Harvard University made the first
documented radio broadcast of speech and music. For this feat, he
used a 50-KHz Alexanderson alternator, manufactured by the
General Electric Co. Telegraph operators on ships crossing the
North Atlantic were surprised on the historic night to hear music
coming out of earphones that previously had emitted nothing but
dots and dashes. Fessenden modulated the alternator's 1-KW
output simply by putting a microphone in series with the antenna of
his experimental station at Brant Rock, Mass. It is likely, but not
certain, that the microphone was water-cooled."

Mother Brakob, please point out, highlight if necessary with a yellow
marker pen, that the transmitter was an ALTERNATOR, not the
damped-wave "spark" type your son scribbled in angry crayon.
Specifically, an ALEXANDERSON ALTERNATOR. ONE
KILOWATT output.

You may wish to give your son a primer on electricity explaining
power losses in resistive conductors. That is important considering
the microphone used by Fessenden was IN SERIES WITH THE
ANTENNA CARRYING CURRENT SUFFICIENT FOR ONE
KILOWATT RADIO FREQUENCY POWER OUTPUT.

Best of good luck on that one, Mother Brakob. [you are going to
need it]

LHA

================================================== =

Additionally, there are some basic technical matters which have
been totally ignored, such as the "sound" produced by attempting
to amplitude modulate a low-audio-frequency-range damped-wave
oscillation by speech or music frequencies. That might be quite
similar to attempting to amplitude modulate a doorbell buzzer and
expect intelligibility from the result.

I would suggest searching a large bookstore for a primer on
electricity and elementary radio, such as "Radio For Dummies."
That does not appear to be in the ARRL list of approved, official
documents but another publisher (possibly 73?) might have it.

Extreme amounts of good fortune on this one now!!!

LHA