Polaris 2001 High-Performance Snowmobile Service Manual (PN 9916690), Page 350Get this manual
ELECTRICAL Alternators
The pulse alternator system is the number of AC sine waves created by the alternator in one revolution of the crankshaftFor example, in pulse system, the alternator will create pulses, or complete AC sine waves, in one crankshaft revolutionThe tachometer reads these sine waves, therefore giving you accurate RPM readingsA pulse tachometer cannot be used on pulse systemIf this is done, the tachometer will read double RPMRefer to the following text for applications