[Arran]

Tim;
I was just going to mention the sand resistors, but Richard beat me to it. Those are a replace on sight item with me, they are the only wire wound resistors I have had fail just from sitting on a shelf. They have a habit of corroding, and the connection between the resistive wire and the ends tends to break down, in my opinion they aren't worth messing with. The two 2 Watt carbon com resistors with the rough bodies should also be checked, they don't behave like sand resistors but they do go up in value.
Regards
Arran