Problem is when I bring it into the kitchen after a time (different each time it happens) the receiver beeps and the temp read ----.
I'm pretty sure it has lost the signal. When I walk to within about 30ft of the transmiter it picks the signal up again.
The WSM is at the bottom of the garden and 35 strides from where I set the receiver, so I guess maybe 100ft.
I do have wifi and wireless phones in the house and everyone has a mobile.
Any suggestion, gratefully received. (received, did you see............)

