U-boat radio performance

[nikimcbee]

What was the range of the early u-boat (WWI) radios? Did they have a seperate room for them? (like the ww2 subs)

[Chock]

Not certain about exact performance, but...
Most WW1 U-Boats had a big clumsy folding mast which took quite a while to erect, and the fact that they had to have such a mast would seem to indicate that the radios were probably a bit crappy in terms of capability.
If you can equate it to WW1 artillery spotter planes, they usually had to reel out a big copper antenna wire (several hundred feet long with a huge weight on the end of it), in order to be able to transmit morse to the artillery batteries they were spotting for, so that they could 'walk' artillery rounds onto the target by means of a simple set of letters to indicate whether to elevate or traverse the guns based on a 'clock' system.
Since they had to do that, and they would have had a clear line of sight to the receiving radio, I'm guessing that the range of WW1 radios was probably really bad, although obviously a WW1 aeroplane would not have been able to carry something of the size and power you could fit in a U-Boat.
If you bear in mind that the Titanic sent an SOS to ships asking for assistance in 1912, and those ships took over four hours to get to the Titanic at full steam, this would indicate that the range of a signal at sea would not be terribly short even before WW1, but then again, the Titanic had some very tall antenna masts on it, much taller than anything a U-Boat would have been equipped with.

:D Chock

[Deamon]

What was the range of the early u-boat (WWI) radios?
In 1907 a radio of 0,2 KW power was installed on an 250t u-boat by the germania yard. The day range was approx. 200nm during the night approx. 500nm. 10 years later the u-boats were able to communicate over thousands of miles with each others.

Did they have a seperate room for them? (like the ww2 subs)
The first u-boats that were equiped with radios were U5-8. The radiostation was installed openly in the e-engines room. U23-26 were the first boats that got a real radio room. If we can consider this a room at all :) Rather a chamber. Later the hydrophone pannels were also installed there.

The radio rooms were either directly in the control room or infront of it. Overall the performance of the radios made huge advances since their introduction till the end of the war. In the later stage of the war the radios got so powerfull that they started to get rid of the radio masts on at least some of the boats. Which has used the net rejector antennas instead.

[smudgegs]

I don't have any specific info about the radio performance but to put it into perspective modern cw (morse) radio range largely depends on the antenna/ariel, and that is the antenna at *both* ends and the atmospheric conditions (weather, solar flux etc) at the exact time of transmission!
By that I mean if you have a lousy antenna but the shore station has a great antenna (as you would expect at a naval base) then the range is considerably improved, ship to ship it will be shorter. That said having an antenna over salt water greatly improves HF performance... lots of variables! :hmm:

Now a random (short) length of wire strung out of my window here in Scotland, is about the worst sort of antenna that will work, and with 10 watts and less I can contact most of Europe using CW, most of the time... the transmitters / receivers may have been poorer then, but they had better antenna locations and much more power so I would expect reliably to get up to a max of about 1,000 miles on HF (at certain times of day only! It's roughly the first "skip" of the radio signal between Earth and the Ionosphere) with much greater range possible but unpredictable.

When the time of day/freq/conditions are against skywave or skip transmission then groundwave I expect would be limited to max a couple of hundred miles purely because of the antennas being relatively low.

All that said I have managed over 1,000 mile two way comms using only 2.5 watts!! Morse code is an amazingly efficient way to communicate.

Finally, all this assumes that they were using HF radios (approx 2 to 30Mhz), if they were using Low Frequency then you'll need someone else as I haven't used that!

Hope it helps anyway,
Smudge:)

[Deamon]

Thanks for the info, smudgegs, although I am not an expert yet on this matter I already took some glimpses and realized that there are a lot of variables in the radio range equation.

And I am looking forward to dissect this subject in detail. Would love to simulated it throughoutly.

[Deamon]

I am wondering where i could get a complete documentation of all intricacies of radio communication ?

I am also wondering whether radio waves can also get refracted as sound waves in water do ?

[iambecomelife]

I will check my sources, although they are a bit light on detail.

On a related note, I never knew that WWI U-Boats had hydrophones; I thought that they only used carbon microphones.

None of my sources have any pictures of WWI hydrophones or microphones, so do you know what they look like? I need to model replacement equipment for the hydrophone station in Silent Hunter III/IV.

Thanks!

[Deamon]

All that said I have managed over 1,000 mile two way comms using only 2.5 watts!! Morse code is an amazingly efficient way to communicate.
I am wondering what was the worst range that you achieved with this setting ?

I hope you are still around.

[Deamon]

Hi iam, how things are going lately ?

I will check my sources, although they are a bit light on detail.
I need to know all about the physic of it and how it interacts with the environment. I need enough data for a proper simulation.

On a related note, I never knew that WWI U-Boats had hydrophones; I thought that they only used carbon microphones.This ARE hydrophones. By definition a hydrophone is a microphone that is made to work in water.

None of my sources have any pictures of WWI hydrophones or microphones, so do you know what they look like? I need to model replacement equipment for the hydrophone station in Silent Hunter III/IV.I think i have one picture or so. I am not sure though if there were any replacement hydrophones at all on board. It seems to me the boat would have to go into a dock for replacement.