tachometer problems

["Robert W. Murphy" <rmurphy@domain.elided>]

While driving to work on Monday in my 1990 Spider, I noticed that my 
tachometer was reading about 500 rpms lower than usual at 80 mph.  It was 
hovering at about 2700 rpm and usually reads 3200 rpm at 80 mph.  I later 
noticed that it will barely pass 3000 now, no matter how fast I am going or 
how much I wind out the engine in any gear.  Is this indicative of the 
tachometer dying?  Or do you think there is a bad connection somewhere?  Where 
exactly is the tachometer sender/sensor?  I was once told that the tach reads 
off the ignition coil.  Is that correct?

Thanks,
Rob Murphy
90 Spider
Coral Springs, FL

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