Once you get it all installed and wired up (the old-style knob fits the new switch shaft), it works just like any setup in a later Gremlin, Spirit, Hornet or Concord. You turn the knob to the right one click and you get low speed, the next click is high. From center, you turn the knob to the left for intermittent operation. It is infinitely variable from about every second to about 30 seconds of delay per swipe. Just set it where you want it. It's nice to have on an earlier Javelin when you get caught in a light rain. Just be very careful to wire it in correctly.
Good Luck!
Bill Dettman
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