20th Century Pre WW1 Wireless Telegraphy

Wireless Telegraphy 1903

In this year Marconi's Telegraph to the USA starts from the UK

Written by Godfrey Dykes

© RN Communications Branch Museum/Library

The contents of this file 1903/1 are listed below.

1. W/T for submarine boats Plate 1 - big plate so scanned in two parts. (Leave as shown otherwise it will not make sense).
2. Index Pages.
3. W/T for submarine boats Plate II - big plate so scanned in two parts. (Leave as shown otherwise it will not make sense).
4. Index Pages.
5. WYSIWYG - just the way the arbitrary scanning method worked.

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The contents of this file 1903/2 are listed below.

1. This file describes the systems used by the Royal Navy. Plain System. In the first half of the 1900's, there were three basic Tunes, A, B and C and the RN used some of them and dabbled with others usually 'A' at sea and 'B' ashore though a few ships had 'B' also: by 1906 for example, the navy had dropped A and B and C was only fitted in HMS Vernon with three other sets on order. They were called 'TUNES' but in reality they were apparatus dedicated to operating on certain bands (wavelengths) and we of course would call them simply frequency ranges. They were however different in power outputs and aerial requirements. All three were Oscillator systems (as opposed to the RN's plain system, although by 1907 the navy had switched totally to the Oscillator system). TUNE A operated on a wavelength 400 feet (122m = 2.5MHz approx) @ 300 watts and known as Short Wave Tune: TUNE B on 1025 feet (313m=950kHz approx) @ 600 watts and known as Long Wave Tune. TUNE C with much more power 2.5kW and much lower frequencies 2760 feet and 4250 feet equating to respectively, approx, 350kHz and 280kHz. Here is some information on the TUNES. The document giving details of TUNE C (below) is extremely fragile and has not worn well. It is literally in danger of dropping to pieces (or turning to dust) and to try and unfold its folded pages would render further harm to it. With great care I have managed to scan the pages without exaggerating the dilapidated state, and now that it is safely copied for posterity, the document itself can, we hope, be stored without further deterioration: see Tune C Chapter One and Tune C Chapter 2 to 4. Jumping ahead (but it doesn't matter there is no strict order) you can get an excellent understanding of 'C' Tune by looking at 1905/6
2. Various bits and pieces - new receiver box for submarines.
3. A spark-gap silencer.
4. Note for Fig 3 - this is the latest Marconi receiver box.
5. A Marconi Agreement - a very confidential affair. Note the "own war purposes" clause.
6. Results of W/T Conference in Berlin August 1903 - I thought that GPO stood for General Post Office!
7. W/T in Somaliland - seemingly a disaster. The camel story is fascinating, more like a lesson in zoology that a 'comms expedition wash up'.

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The contents of this file 1903/3 are listed below.

1. Admiralty instructions for TUNE 'A' and TUNE 'B' (Tune A & B) - note the distances achieved, the spark-gap's set and the vulnerability to jamming.
2. Instruments under Trials:
Coherer - "at times results have been excellent getting beautifully clear signals from Portland."
Radioscope - gives poor results !
Tuning. See Plate III .
The conclusions are very interesting especially the last paragraph which points the finger at the coherer.
3. Theory - of a natural frequency of an aerial being 'sparked' directly.

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The contents of this file 1903/4 are listed below.

1. Report of Inspection of Marconi Company's Works and W/T Stations - covering Chelmsford, Niton and Poldhu.
2. Captain Jackson is extremely complimentary towards Marconi who is absent from the country during his inspection. Note the merit of having the dynamo as expressed bottom of page 4. Captain Jackson mentions that "their ordinary operators are probably are probably better electricians and telegraphists" meaning of course, better than those in the RN. That point becomes a potential problem later on. He considers that there are too many W/T shore stations and suggests that some could be closed down. He hints at the W/T station at Portcernu could do some damage to Marconi, and possibly it (and others) could assist an enemy of the Realm!
3. Syntonic Systems of W/T for ship work, originally Captain Jackson's baby and now being designed and manufactured by Marconi has disadvantage and advantages over the UNTUNED existing RN equipment fit. Captain Jackson states four advantages, one disadvantage and one observation that there would be a small price increase.
4. Captain Jackson, in referring to TUNED and UNTUNED means OSCILLATOR and PLAIN respectively which I have already explained in Tune A & B
5. The very idea of large battle fleets always being together at sea necessitating just a handful being fitted with W/T, is to say the least bizarre. Apart from fitted ships sinking, out of action, or riddled with defects, can you imagine the number of deliveries from fitted ships to non-fitted ships by closing manoeuvres, flashing light, seaboat and jackstay transfers ? One reason for this limited fit is that with too many ships, fitted, W/T practice would be near on impossible.
6. Marconi Company Works at Chelmsford manned by boys and women trained by Marconi because trained men were impossible to recruit.
7. Magnetic Detector - the most sensitive receiving apparatus yet invented but for telephone work only.
8. The diagram of a SEND/RECEIVE Aerial change over switch (COS) shown on page 5 of this file is amusing, nothing more, although recognised as being practical. Later on I will show you the Morse key used for such an event which has two keys on the same platform. It reminds me of the HF Contacts on a submarines HF telescopic aerial which don't engaged unless the mast is fully raised.
9. Mercury (instead of silver shavings) Coherer (Castelli Type) - too vulnerable and unreliable.

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The contents of this file 1903/5 are listed below.

1. Large Power Station at Poldhu Cornwall.
2. Poldhu spark length can be a massive 1.75 inches.
3. Lizard W/T Station.
4. Niton W/T Station.
5. Instruction for Muirheads Automatic Morse sending apparatus - the very first Morse autohead.
6. Maximum speed was 18wpm but unless well set-up and correctly adjusted, shorts are apt to be missed out over 15 wpm. The navy will settle for a reliable 16wpm system. That little word 'shorts' I have just used is how Morse code was referred to by all (commercial and military) SHORTS being a dot and LONGS a dash (both plurals). The Morse ink-marking attached to the coherer marked these shorts and longs before earphones were used to actually listen to the signal. Mind you, it is a good job that they didn't take the anagram of "The Morse Codes" (and, as you will soon see there was more than one) too literally, or they would have been waiting a long time for 'longs' ! Anagram = Here comes Dots (shorts that is).

Up to this point (and the point continues for some time yet) you can clearly see that although there is a great flurry of activity, and, some ground-breaking W/T events have already taken place (some back to the 1890's) it can hardly be said that the ROYAL NAVY is a lead figure in either the technology of wireless or in the number of equipments it owns. The tour of the Marconi premises mentioned in this section, did much to bring Captain Jackson fully on to the side of Marconi and from this time on he did everything in his power to support, encourage and, more importantly, procure equipment from his one time professional adversary and competitor. At this time, virtually all commercial outlets whether W/T shore stations or merchant mariners, employed professionally trained (nearly always Marconi trained) personnel (officers, operators and clerks) but the navy was a few years away from emulating this with the result being that the part-time telegraphists were becoming the weakest link in the progress stakes.