Hi Paul,
Detectors are readily available and getting one close enough should be no problem.
I still haven't been able to ID or age it yet but electrically it doesn't need much.
Try a google search for crystal radios and youd be surprised at just what comes up and how many people are still experimenting with them.
Some poor quality pics of my other projects are accessible from my website.
http://mysite.wanadoo-members.co.uk/simoshomepage/ Simon.
