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kg6saj
12-23-2004, 12:17 AM
Happy holidays.

I happened across this audio file about a month ago. It was one of those link-from-a-link-from-a-link kind of things. This is the only spark telephony recording that I've come across in searching the internet. [This audio file is also six links off of (K2TQN) John Dilks' old radio and radio history web-site.]

When you click the 'hear' link in the paragraph above fig. 8 on this web-page,
http://www.hammondmuseumofradio.org/spark.html
you should hear a re-creation of what the first "telephony transmission employing spark might have sounded like".

[note -- If the white graphs on a black background are difficult to make out, you will find most of the information duplicated, with black graphs on a white background, here,
http://www.acmi.net.au/AIC/SPARK_SOUNDS.html
however, this page does not have the addendum, and the link above figure 7 is dead.
As an aside, the "Essays Index" link at the bottom of this page has a few dozen history-type links for radio, tape and wire recording, cinema, etc. Even though a few of the links are dead, I found some of the remaining ones quite interesting.]

If you listen to the four spark gap telegraphy recordings (farther up the page) and like what you hear, there are three more that you can play at the bottom of this page,
http://amfone.net/zmspark.html



Reginald Fessenden was an inventor with some 500 patents to his name. Among them was a patent for an electrolytic detector which can be seen here,
http://chem.ch.huji.ac.il/~eugeniik/history/fessenden.html

Another was his electric oscillator (sonar). Picture here,
http://oceanexplorer.noaa.gov/library....ng.html (http://oceanexplorer.noaa.gov/library/readings/subsignaling/media/lowering.html)
The "Library: Readings..." link has a description of how it worked.

And another good web-page by Belrose (VE2CV) that discusses the early history of radio science is at
http://www.ewh.ieee.org/reg....st.html (http://www.ewh.ieee.org/reg/7/millennium/radio/radio_radioscientist.html)



If anyone knows of any other spark telephony recordings, please post the link(s) or information. Your sharing will certainly be appreciated. There are others, besides myself, that would enjoy hearing them.

I wonder what it would have been like to have been there and part of it, when it all began.....if I could get my hands on a time machine, this time period would surely be one of my stops.

73 - Tim - KG6SAJ

KC0W
12-23-2004, 12:54 AM
I also have spent too much time searching the net for spark gap recordings. I think you have listed all of the ones that I have come across as well. Nice job listing them here.

There is even one site that walks you thru how to construct a spark gap transmitter. From what I recall, the author claims that you can wipe out pretty much the whole ham spectrum by transmitting with it!!


Tom kcØw

KC0NBW
12-23-2004, 02:58 AM
Quote[/b] (kc0w @ Dec. 22 2004,17:54)]I also have spent too much time searching the net for spark gap recordings. I think you have listed all of the ones that I have come across as well. Nice job listing them here.

There is even one site that walks you thru how to construct a spark gap transmitter. From what I recall, the author claims that you can wipe out pretty much the whole ham spectrum by transmitting with it!!


# # # # # # # # # # # # # # Tom kcØw
not only the ham spectrum, just about everything from dc to light! http://www.qrz.com/iB_html/non-cgi/emoticons/laugh.gif http://www.qrz.com/iB_html/non-cgi/emoticons/laugh.gif

KB1GYQ
12-23-2004, 03:04 AM
Quote[/b] (kg6saj @ Dec. 22 2004,20:17)]http://www.hammondmuseumofradio.org/spark.html
you should hear a re-creation of what the first "telephony transmission employing spark might have sounded like".
I just love that one! Voice transmittion existed before CW! (That's Continuous Wave for all you Morse Code fans)

KB1GYQ
12-23-2004, 03:17 AM
You'll love this one too [URL=http://www.smecc.org/j_cbose_-_radio_and_microwaves.htm[/URL]

waveguides, horn antennas, dielectric lenses, various polarizers and even semiconductors at frequencies as high as 60 GHz in the late 1800's!

kg4kww
12-23-2004, 04:08 AM
Quote[/b] ]KB1GYQ -- I just love that one! Voice transmittion existed before CW! (That's Continuous Wave for all you Morse Code fans)

You tellum KB1GYQ, long live phone.

Lets embalm and bury CW.

KB1GYQ
12-23-2004, 04:32 AM
Quote[/b] (kg4kww @ Dec. 23 2004,00:08)]Quote[/b] ]KB1GYQ -- I just love that one! Voice transmittion existed before CW! (That's Continuous Wave for all you Morse Code fans)

You tellum KB1GYQ, long live phone.

Lets embalm and bury CW.
Now, now... Damped Wave has been outlawed so we all use some form of modulated Continuous Wave. Some people enjoy using Morse encoded modulated Continuous Wave, and should be permitted to enjoy it!

N8CPA
12-23-2004, 03:38 PM
Okay, I concede. Voice modes are older than CW--but that just supports my contention that gum flapping is so archaic that it should be banned from the Amateur bands. All of our permitted emissions should be text and image, since that's the latest and greatest cutting edge stiff that everyone's promoting. And since Morse is the basic text mode, constituting fundamental radio literacy, testing should be required. [/sarcasm]

K9STH
12-23-2004, 04:01 PM
Spark predates CW and both the American Morse code and the International Morse code were used on spark. Until after World War I amateurs actually had to have a different license to use CW rather than spark (of course this was after the implementation of licenses by the Federal Government).

As such, the use of Morse code on wireless (or radio) circuits definitely predates voice. However, CW (continuous wave) telegraphy did not come into being until the use of vacuum tubes. Rotary spark and Poulson alternators gave a much "cleaner" signal than just using the old fixed spark gaps. But, it was not until transmitters using vacuum tubes were constructed that true continuous wave (CW) transmissions were possible.

Fessenden was also transmitting voice using methods other than modulating spark. He was transmitting voice and music to pleasure boats travelling along the St. Lawrence River before 1900. But, this used techniques more aligned with inductive coupling than true r.f.

Glen, K9STH

kg6saj
12-23-2004, 10:36 PM
Quote[/b] (KB1GYQ @ Dec. 22 2004,19:17)]You'll love this one too

waveguides, horn antennas, dielectric lenses, various polarizers and even semiconductors at frequencies as high as 60 GHz in the late 1800's!
Yes, I would like to see that.

I tried the ol' copy-and-paste, but #http://www.smecc.org/j_cbose_-_radio_and_microwaves.htm (http://www.smecc.org/j_cbose_-_radio_and_microwaves.htm[/URL) #just gets me a "page not found".

When I strip it down to #[url]http://www.smecc.org/ #it of course takes me to the home page, but there's so much there that I can't seem to find what you're referring to.

A little help please.
Thanks

KB1GYQ
12-24-2004, 01:51 AM
http://www.smecc.org/j_c__bose_-_radio_and_microwaves.htm

seems there's a glitch in posting links with successive underscores....

kg6saj
12-24-2004, 02:14 AM
Yep, that one works fine.

Just have a minute right now to scan thru it, but what I saw looks very interesting.
Prism attenuator - Cool
I'll certainly take a closer look when I get the time.

Thank you, sir. http://www.qrz.com/iB_html/non-cgi/emoticons/smile.gif

K7FE
12-25-2004, 05:40 AM
GYQ,
I was very impressed with the information on Bose. What a great scientist. He was truly 50 years ahead of his time.

73,
Terry, K7FE

kg6saj
12-25-2004, 10:07 PM
Quote[/b] (K9STH @ Dec. 23 2004,08:01)]Fessenden was also transmitting voice using methods other than modulating spark. #He was transmitting voice and music to pleasure boats travelling along the St. Lawrence River before 1900. #But, this used techniques more aligned with inductive coupling than true r.f.
Glen, I'd like to hear/read more about that.

K9STH
12-26-2004, 12:33 AM
SAJ:

Basically Fessenden used very long antennas (like several miles) and then applied audio to them. The antennas on the boats were basically large loops.

This is "akin" to some of the systems that were used with "wireless" headphones attached to a stereo amplifier. The amplifier output was connected to a large wire "loop" and the headphones had a smaller "loop". The "sound" was carried by the magnetic field just like in a transformer.

There have been some descriptions of Fessenden's experiments using this technique in various publications over the years. I believe that (but don't make me "swear on a stack of Bibles") that one, or more, have appeared in the AWA newsletter. There were articles in possibly the old Popular Electronics magazine or Elementary Electronics magazine.

Glen, K9STH