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I purchased a NOS regulator/rectifier made in Spain by Saprisa. I don't know if it was standard on any Ducatis or Mototrans Ducatis but it seems to be made for a three wire alternator as on my W/C Scrambler. The terminals seem pretty clear. Two yellows and a red from the alternator. A terminal for the battery and a terminal for the coil marked brown. After making all connections I'm not getting spark. I isolated the regulator and connected the battery straight to the coil (total loss) and I got spark. It doesn't seem like the terminal marked brown (coil) is getting powered. Any advice or is the regulator not working.