Jeff Liebermann <jeffl@cruzio.com> hath wroth:

>So much for the antenna in the wrist band idea. So, the question is,
>what type of tiny antenna will work with such a field strength at
>60KHz. I dug through the FCC ID web pile looking for an inside photo
>of Casio watch, but couldn't find anything. I'm gonna have to either
>break one open, and/or calculate the field strength of a very small
>ferrite rod antenna (later).

I found a photo of the insides of a watch. See:
<http://tf.nist.gov/general/pdf/1877.pdf>
on page 11-12. It's a small 2cm internal rod antenna.

There are some ferrite rod antenna design notes on the Temic/C-Max
chips used on some receivers:
<http://www.c-max-time.com/downloads/search.php?search=CME6005>
<http://www.c-max-time.com/downloads/search.php?search=CME8000>

There's some on antenna matching here:
<http://www.c-max-time.com/downloads/getFile.php?id=437>

Watch antennas:
<http://www.c-max-time.com/products/productsOverview.php?catID=5>
See the photos of the various antennas. Too bad there's no specs.

I'll grind out the field strength numbers later. I've been living in
the microwave region for so long, that I'm having problems with LF
calcs.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558