BUILD A HISTORICAL TELEGRAPH CONNECTION
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with 2 Sets, 2 Wires and a 4.5 Volt Battery ...
1st Wire
+-----KEY----->........................>-----KEY-----+
| |
SOUNDER Main Set Remote Set SOUNDER
| 2nd Wire |
+---BATTERY---<........................<-------------+
It is assumed, that one station ( eg. the remote one ) has the KEY = ON
with its SHORT-CUT-LEVER to get the message from the other station.
It was discovered that only ONE CUPPER WIRE is sufficient: The EARTH can be
used as the electrical conductor. And the invention of the 3-POLE-KEY made
the Short-Cut-Lever obsolete: Its rest position is the "Receiving Mode" ...
HISTORICAL REMARKS ...
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Before the invention of the TELEPHONE, TELEGRAPHY was the only possible
high-speed communication to remote locations. In 1837 SAMUEL F.B.MORSE had
invented a device to sent messages coded in DASHES & DOTS (& SPACES !) to a
receiving device. When the SENDER-KEY is pressed down, the RECEIVER, driven
by an ELECTRO-MAGNET, pushes down a PEN against a STRIP OF MOVING PAPER. In
the same way as the sender key is pressed, DASHES & DOTS are placed on the
paper-strip and this could be read and decoded to the message sent.
Later the telegraph operators realized, that they could HEAR(!) the message
without using pen & paper - just by its CLICK- & CLACK-SOUNDS: A "SOUNDER"
became now a simpler receiver, placed in a RESONATOR to amplify the sound.
( Set the sounder in an open, upright cookie-box to have the same effect !)
R E M A R K : These "CLICK / CLACK" SOUNDS are D I F F E R E N T from
the CW SOUNDS ( eg. "dit-dit-dit_daa-daa-daa_dit-dit-dit" = SOS ) of the
wireless communications ( eg. by SW-Radio-Amateurs ) we are familiar with:
THE INTERNATIONAL MORSE CODE:
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A .- F ..-. K -.- P .--. U ..- 1 .---- 6 -....
B -... G --. L .-.. Q --.- V ...- 2 ..--- 7 --...
C -.-. H .... M -- R .-. W .-- 3 ...-- 8 ---..
D -.. I .. N -. S ... X -..- 4 ....- 9 ----.
E . J .--- O --- T - Y -.-- 5 ..... 0 -----
Z --..
T I M I N G :
A DASH is equal to 3 DOTS; SPACE between parts of same letter equ. 1 dot;
SPACE between two LETTERS equ. 3 dots; SPACE between two WORDS equ. 7 dots
Famous TEST-QUESTION to students: " How much signs has the MORSE CODE ?"
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The RIGHT ANSWER is: "MORSE-CODE consist of 3 SIGNS: DOT, DASH & SPACE !"
Have a Look at my » MORSE TRAINING SET «, bought 1956 in Berlin ...
... with BUZZER, 3-POLE (WWII-)MORSE KEY ("How cute!") & MORSE PRIMER.
Have a look at the "complete" MORSE ALPHABET ...
My 2nd MORSE-KEY was made 1934 by TELEFUNKEN / Germany ...
15 cm x 8 cm / 6" x 3_1/8"
Enjoy reading about the TELEGRAPH's HISTORY and the people involved ...
Tom Standage / » The Victorian Internet « / Walker ISBN = 0-8027-1342-4
... LOOK !!! RICHTSTRAHL-ANTENNEN-PEILKARTE / BERLIN !!!
Have a look at the WWII US Army Telegraph Set TG-5-B ...
impressum:
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© C.HAMANN http://public.BHT-Berlin.de/hamann * 05/05/14
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