On Mon, 25 Nov 2019 07:57:16 +0200, Mikko OH2HVJ wrote:

As others noted, it is a thermal fuse.

The turns are there for pliers or other tool to absorb the heat while
soldering the thermal fuse to the PCB. It's quite easy to blow a low
temperature rating thermal fuse while soldering.

Ah, thanks very much for that, Mikko; the missing piece in the jigsaw!

What't the schematic like, are the resistors connected in such a way
that they would heat during some failure condition and blow the fuse ?

I don't have a schematic, but that's been my working assumption
throughout. It makes sense that way.



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