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One problem is that flagging of one of the soil sites was removed. (I found the bare metal wire of the flag several meters away today.) Also, the TP01 at this site had been removed from the ground and is lying on the surface (though it appears to be in perfect shape). I have spent a lot of time (even at low sun angles this morning) looking for traces in the area (I know to within 7m x 7m), but haven't been sure enough of any location to start digging for the buried cable ends. My current idea is to buy a metal detector! In any case, I'll have to rebury the TP01 after I find its PIC processor.