Do you really want a field strength meter, or just a relative indicator?
Hams often misuse the term.  A field strength meter is a calibrated
receiver with a calibrated antenna, not an inexpensive proposition.
 
What hams usually mean when they use the term, is just a simple meter
with crystal detector, sometimes tunable, with a short antenna for
getting an idea of how to adjust antennas or even to find hidden
transmitters when getting very close.
 
73 DE K6DDX
--- Maximus 3.00
---------------