e.o.t./ chadburn telegraph

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pucho812

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Decided we need one at the studio  to communicate between the tech room,  front office, etc and the control room.  Obviously it would not have  the  Typical dial positions  as listed below and we would  have more studio friendly dial positions like Coffee, Alignment,  setup, etc...

Flank ahead (1940-) (USA only)
Full Ahead
Half Ahead
Slow Ahead
Dead Slow Ahead
Standby
Stop
Finished With Main Engines
Dead Slow Astern
Slow Astern
Half Astern
Full Astern
Emergency Astern ( 1940-)
Any orders could also be accompanied by an RPM order, giving the precise engine speed desired. Many modern ships have the following dial indications:

Full Ahead Navigation (on notice to increase or reduce)
Full Ahead
Half Ahead
Slow Ahead
Dead Slow Ahead
Stop
Dead Slow Astern
Slow Astern
Half Astern
Full Astern

 
EOT took me back to my days in the early computer industry when they used magnetic tape to store data. EOT stood for end of tape.

Cheers

Ian
 
Im189908Cass-Chad.jpg
 
> How many wires

"Tele" means 'far', not 'electric'.

The secrets of the ancients seem to be lost. However it seems to be all mechanical. And of course what fool of 1870 would trust his ship to electricity?

Telegraphs from the bridge to the engine room first came into use about 1850, and consisted of a dial and lever handle on the bridge, connected by rods and bell cranks, to a dial with a pointer and bell in the engine room.
These continued until about 1860, when the shafting telegraph began to be used. It was usually made with a pedestal dial and lever on the bridge, and connected with solid shafting and cast bevel wheels (which were filed by hand) to an engine room indicator having a dial, pointer and bell.
This telegraph was capable of working through six pairs of wheels and about 50 feet of shafting, and was generally accompanied by a call bell to act as a reply.
In 1871 John S. Gisborne invented a telegraph, in which the communicating medium was a single wire ; the author has failed to secure definite information as to how this single wire operated the two movements, viz., the order and the answer.
In the early seventies Messrs. Chadburn's put on the market a patent endless hand telegraph, which consisted of a pedestal on the bridge with dial and lever, connected by wires and chains to an indicator with dial, pointer and bell in the engine room. Very soon this system was duplicated, being made to work from the engine room to the bridge as a reply.
The old shafting telegraph was superseded by this system of wire and chain, as it was found to work accurately at much longer distances and had the advantage of a reply.
This is practically the telegraph of the present day as fitted in all merchant vessels. At later dates minor improvements were added, such as :—the Duplex Gong Indicator, giving a deep tone gong for ahead orders, and a shrill tone for astern orders. Double dials were then used in bridge instruments and made to sit fore and aft, so that the lever was moved ahead for ahead orders and astern for astern orders.
In about the year 1885 telegraphs with shafting and bevelled wheels were greatly improved by employing wheels with machine cut teeth, and later on by the use of hollow steel shafting. All the larger vessels of the Navy were fitted with this telegraph, but owing to the limited travel of the operating lever and of the indicator pointer, it was most difficult to obtain accurate results on account of torsion and backlash.
In 1893 Chadburn's patented a synchronising device, which caused the pointer of the engine room instrument to stand in the centre of the order. This consisted of a star wheel on a flexible spindle and a spring-controlled roller working into the teeth of the star wheel.
These telegraphs are not confined to ships only, for they are to be found in all sorts of places where communication to the engine room is required quickly. They have been fitted for the working of large bridges, of lifts, as at Shanklin, for motor railway coaches, motor cars, many large electric generating stations, quarries, mills, submarines, air-ships and floating docks; one was also used for controlling the Big Wheel at Earl's Court.
  link

Another reference on electrified theaters and other shows has a modified Chadburn.
 

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PRR said:
> How many wires

"Tele" means 'far', not 'electric'.

The secrets of the ancients seem to be lost. However it seems to be all mechanical. And of course what fool of 1870 would trust his ship to electricity?
I tried googling "engine order telegraph " and the answers pointed primarily to digital devices and secondarily to electrical devices. I should have added "mechanical".
 
abbey road d enfer said:
I tried googling "engine order telegraph " and the answers pointed primarily to digital devices and secondarily to electrical devices. I should have added "mechanical".

Yes, current ones used are fancy old displays and electronics.
 

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