Crystalyte 12 FET 24-74V analog controller

I can use another controller for my Wavecrest Tidalforce S-750C bike with the HS3540 motor. The analog controller is a bit old fashioned and I really don't know what the difference is between an analog and digital controllers but I grabbed an inexpensive one from eBay this morning. I particularly like Crystalyte controllers because they have On/Off switches. Very handy!

http://www.ebay.com/itm/231109726080?ssPageName=STRK:MEWNX:IT