its at the "accumulating crap" stage. just a big pile of second hand bits and a licsenced running car i dont want to disable. CA on stand
dazza

Cool - Was not sue if it was a square or sine wave. As setting it up with a aftermarket VDO speedo at the moment. And they indicated that nissan use hall effect sensor. Which got me questioning what I had researched.

Still need to look into speed sensor input to comp. Have put this job on the back burner till I get the car on the road. Would like to look into plms unit to feed the input to the ecu. Or I will get hold of a stock s13 speedo and break it down to a black box and do the same thing.

Have got the oscilliscope and all the gear, but not the time unfortunately. And the car seems to be running allright with out it at the moment.

Want to have a look at you project, so hopefully can come to Garage run

no reed switch and magnet
ie: square wave pulse generator
easy to replicate ...but signal is processed in speedo. i'm trying to find out how. did you look at that web site i mentioned before
http://www.plmsdevelopments.com/index.shtml
these guys do a box to do the processing for about $50 . they do SR into 1600 looms n stuff. ecu between sr and ca very similar and both came in s13 so it should work.
let me know how you get on.
dazza
i gotta buy an oscilloscope dick smith do one for $128 now

Chasing some info on the original Nissan speed sensor on the CA gearbox.

I assume its a hall effect type ??? Can someone confirm this please.

Cheers