I have a tach amp that I have taken apart and removed all the potting compound. Being that we are in the same city, we should get together and see what we can do about drawing a schematic and making a test jig to check these out. I was in the electronics industry for 30+ yrs as a field engineer for an aircraft electronics company. My tach works on a random and unusable basis. I tried the spacer trick with absolutely no success. The pick-up point seems to be a long way from any spot on the harmonic balancer but I have nothing to compare it with.


'83 300D 361,000 mi. and going strong