Re: [PSUBS-MAILIST] radio link

The antenna length for VLF and energy requirements for the radio will far surpass that of a VHF radio.

R/Jay

Respectfully,

Jay K. Jeffries

Andros Is., Bahamas

Vive vt vivas
? Live that you may live

From: owner-personal_submersibles@psubs.org [mailto:owner-personal_submersibles@psubs.org] On Behalf Of Rick and Marcia
Sent: Friday, April 04, 2008 07:29
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] radio link

Hi, Max - sorry for the late response, I've been overseas.

Thanks for the great info. Now to decide whether VLF would be easier to implement than a hard-wire to the float. Guess the ham guys will fill me in there. I know that VLF carries less information - or is that ULF . . .

Cheers and thanks again :-)

Rick

----- Original Message -----

From: Max Elliott

To: personal_submersibles@psubs.org

Sent: Saturday, March 08, 2008 7:04 PM

Subject: Re: [PSUBS-MAILIST] radio link

Rick,

My HAM friends tell me you are looking for a Very Low Frequency (VLF 3KHz - 30KHz) set up like the military uses, and the good news is that you can DIY one fairly easily. (So they said.). I believe that this frequency gets some 20 meters of penetration, but that's just a ballpark rumor I have.

I haven't built one, but I'm connected to some hams in Napa and Washington state and would be happy to get you some contact information if you're interested in talking to them. They will have the math at their fingertips to tell you what your power and range requirements will work out to. They'd also know how to avoid stepping on any legal and military toes.

http://www.radio-flier.com/diy_corner.html - you'll find VLF for an example receiver. I would advise google/shopping around for more information.

I'd bet the HAMming community would be happy to help someone building a PSUB. It just seems like the hard-science, unique kind of projects they enjoy.

--Max Elliott

On Sat, Mar 8, 2008 at 6:29 PM, Rick and Marcia <empiricus@telus.net> wrote:

Has anyone figured out how to establish a radio/video link with a surface vessel?

My somewhat non-tech mind is thinking of a hard-wired connection with the antenna attached to a diver's float.

How far from the transmitter can you run an antenna?

I have offers from the Canadian Coast Guard to act as standby divers but I'd like to give them a play-by-play on her maiden voyage.

Rick Lucertini

Vancouver, Canada