[Vwdiesel] Tach for Diesel

[Wade Yorke]

	I had a 1.9TD installed in my '84 Westy and now trying to get a tach 
hooked up.  Apparently I would have to use a signal converter  (Dakota 
Digital   DSL-1 rev. A  ALTERNATOR TACH INTERFACE UNIT  getting signal 
from W terminal on the alternator) to use the stock tach.
	The other possibility would be to use an aftermarket tach if one is 
available that would work with a diesel without the expense of the 
signal converter.
	Someone had mentioned to me to get a tach from a '86 turbo diesel 
Jetta and swap it with the Vanagon gas tach.  I got the diesel tach but 
the mechanic doing the install could not see how it could work.  I know 
nothing about electronics so I am looking for suggestions.

p.s. if I do go the signal converter route, it has to be calibrated.  
Do diesels idle at a known rpm so I could use that figure as a 
baseline?

Thanks
Wade Yorke
Nova Scotia