Allen,
I was telling my beekeeing friend (he's a chartered engineer) about you
re-queening problem and he suggested that you might like to get in touch with a
Mr. Tom McEwan at Lawrence Livermore Labs. Tom McEwan is working on a device
called MIR, Micropower Impulse Radar, which could locate the queen (because of
her size) from outside of the hive. It should be able to pinpoint her to the
actual frame she is on. My first question was what about radiation but, as this
was so low, it is difficult to measure and would appear not to be a problem.
 If this device proved to be accurate in locating the Queen then it should
reduce labour considerably.
Hope this is useful. Would you keep me posted on any results?
 Allister
 
 
 
--
Allister C. Guy