XPost: uk.d-i-y   
   From: ianREMOVETHISjackson@g3ohx.co.uk   
      
   In message , David Wade    
   writes   
   >On 06/10/2021 18:47, gareth evans wrote:   
   >> On 06/10/2021 18:43, gareth evans wrote:   
   >>> I have been called uppon by SWMBO to repair her Pifco Xmas   
   >>> tree lights which she purchased over 5 years ago.   
   >>> (Yes, we have plenty of modern LED versions to   
   >>> replace them)   
   >>>   
   >>> 1. The instructions say that if one bulb of the 20 fails,   
   >>> then the res will remain illuminated. What's the technology   
   >>> here because they're all wired in series?   
   >>>   
   >>> 2. Is the Fuse Bulb a capacitive unit, because I get a momentary   
   >>> flick of the ohmmeter?   
   >>>   
   >>  Sticky key ... 50 years ago   
   >>   
   >The bulbs are designed to fail as a short circuit. So as more fail the   
   >others get more overloaded ...   
   >   
   Yes. The filament support wires keep it under tension. There's a loop of   
   wire welded to one of the support wires, and it loops around the other   
   support wire (but doesn't touch it). If the filament breaks, the support   
   wires spring apart, and the wire loop shorts one to the other.   
   --   
   Ian   
      
   --- SoupGate-Win32 v1.05   
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