The Crawford cell having two chambers was mounted vertically on a table in a water-jacketed incubator maintained at 37.8°C.
Four eggs were placed vertically in each chamber with their narrow side down using holders on Plexiglas shelves. The MWsignal was routed from top to bottom. Control eggs were placed in the same holders outside of the cell but in the same incubator. Matching of the Crawford cell was performed by adjusting the double stub tuner prior to each exposure period using dummy egg samples.
Temperature increase in the samples was ~1.5°C at 5 W. Positive control was performed by placing eggs in a water-tight bag in a 43°C water bath for 1 h.