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Thanks for the response postdog
Yep, I did that with the tv and the dvd recorder. I'm on the Sandy Heath transmitter, near Cambridge. I'm a retired Computer Field Service Engineer, and in the early days of 300 baud modems which were being increased in speed, we had masses of trouble calls, but when we got to site it was NFF (no fault found)
Signal strength and reception can change in the blink of an eye, last for a second or up to all day. Then it can run troublefree for days or weeks.
OS