The Ludlum 43-2 from eBay arrived today. Seems to work fine.
Tested briefly on my 3 main sources and got these results ( with virtually
Radium dial ( through glass) = nothing
Fiesta ware = a few puny slicks
Smoke detector = 40,000 cpm.
Smoke detector element is still in the smoke detector, but with cover
removed (only for tests). The geometry of the detector base is such that the
AM 241 is still recessed about 3/16" away from the closest access point, so
there is some air distance involved.