Gee, could this be the very same lens I first mentioned just about 2 years ago
in this thread ?? (Actually, that thread leads to a fall 1999 thread where we had a very interesting discussion on Fresnel lenses.)
Here is a pic of the lobby of the USCG ANT School at Yorktown. At the time Heather and I visited (August 99 I believe) the OIC of the school told us the only size lens they did not have was a 3½.
First Order beehive and 2nd order bi-valve
Dave
[This message has been edited by Dave H (edited 06-01-2002).]