Dear audiophiles, be quiet

Jan Panteltje wrote: ________________________

** That would not be great news.

The cross Atlantic link was allegedly made with *10uW* !!!

.... Phil

On a sunny day (Mon, 6 Nov 2017 03:03:09 -0800 (PST)) it happened Phil Allison wrote in :

Sorry, I did cut and past from your Aussies site:

I do get around, that news site is repeated here on 70cm (~430 MHz) on Sunday evening

Yep, he is allowed 10 mW maximum. but that relatively short antenna results in less transmitted power.

For submarine commienukeations megawatts are used and hundreds of miles long antennas

I am getting interested in VLF commienukation, downloaded Spectrum Lab just now, unfortunately it only runs in Win 98 or something. Now there is some code to write for Linux... Not that hard I suppose, already wrote a spectrum analyzer.. And have some VLF filter software. What is interesting is what sort of codes and modulation systems modern subs use on those frequencies. Maybe those just use satellite.

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** Being 50m or more under the ocean does increase the attenuation by a few dB .....

.... Phil

On a sunny day (Mon, 6 Nov 2017 04:13:43 -0800 (PST)) it happened Phil Allison wrote in :

I am not sure at all it works deep under water, but for the reply that had to surface, or send something to the surface. In WW2 that coding system used was 'enigma'

It was hacked,

There were some clever solutions, subs would transmit their position and weather report on VLF, but that allowed the other powers to get their position. Near the end of WW2 Germany had a coding system with much shorter transmissions (few ms) that could not easily be located, but it was too late for them.

This is interesting:

More:

etc etc

beep

At the end of the war the german level of technology had become impressive - thank god it ended in time to avoid it being used much.

NT

you said.