Tach Filter ???
Pro
Joined: Apr 2005
Posts: 603
Likes: 2
From: Illinois, USA
Originally Posted by mvftw
If your tach filter is bad or not connected, what is the symptom?
Does the tach read higher values?
Does the tach read higher values?
In most cases, it was supposed to protect the delicate electronics in the dash that run the tach. I can only speak about my experience with my '77 ...even bought a replacement board that didn't work until I re-did all the solder connections.
Brian.
Le Mans Master
Joined: Jun 2002
Posts: 8,339
Likes: 24
From: I can walk to MA
Recently, someone reported double values on their tach ...
turned out to be an adjustment on their replacement tach circuit board.
It is my professional opinion that the tach filter will not
effect the signal - to read consistently offset. The problem is
more likely in the circuit board. A faulty filter might give erratic
readings, or allow the new circuit board to become damaged from high
voltage transients.
Here are a couple links, one long post on filetrs, and an analysis
that I did of the two filter circuits in question.
http://forums.corvetteforum.com/showthread.php?t=913235
http://nhvette.homeunix.com/ftp/in/N...ilter_comp.pdf
turned out to be an adjustment on their replacement tach circuit board.
It is my professional opinion that the tach filter will not
effect the signal - to read consistently offset. The problem is
more likely in the circuit board. A faulty filter might give erratic
readings, or allow the new circuit board to become damaged from high
voltage transients.
Here are a couple links, one long post on filetrs, and an analysis
that I did of the two filter circuits in question.
http://forums.corvetteforum.com/showthread.php?t=913235
http://nhvette.homeunix.com/ftp/in/N...ilter_comp.pdf
