Modulation methods

radams2000@gmail.com writes:

> The now-discontinued coastal marine navigation system (the name
> escapes me) used a carrier down below 100khz if I remember correctly.

Are you talking about GMDSS? 
-- 
Randy Yates
Digital Signal Labs
http://www.digitalsignallabs.com

On Wed, 12 Jun 2013 16:57:23 -0700 (PDT), radams2000@gmail.com wrote:

>If the speed of light were about a million times slower, then you could jus=
>t connect a microphone directly to an antenna and you would have your own r=
>adio station! Unfortunately, given that we can't change the speed of light,=
> your antenna would need to be about 1000 miles long. Hence the need for mo=
>dulation.=20
>
>The now-discontinued coastal marine navigation system (the name escapes me)=
> used a carrier down below 100khz if I remember correctly. That's a pretty =
>big antenna.
>
>Bob

ELF?


Eric Jacobsen
Anchor Hill Communications
http://www.anchorhill.com

Loran-C