I just disconnected every multi-pin connector in the rig that carries
audio or rf and wiped the pins and applied some 'switch cleaner'
lubricant. I also removed several screws around chassis components
and antenna connector and cleaned the mating surfaces with a glass
fibre brush, wiped with same lubricant and refitted screws. The rig
is stable again. Seems that the TS-440 must have some horrendous rf
curents circulating around the chassis that can't tolerate a few
milliohms of contact resistance. Now we'll see how long it stays
stable!

Oh for a solid cast aluminium chassis.

73 de Richard G4BBH