I wanted to add delay ("intermittent operation") to the Wonderbus's windshield wipers. The Wonderbus has a 12V system, with 2-speed wipers and dash-mounted switch. I purchased and assembled a Velleman wiper delay kit, soldered the bits onto the circuit board, and wired it in and Hey Presto! I now have three delay settings in addition to the original slow/fast settings.
I have posted two .pdf files (you'll need the free Adobe Reader software to view them) showing the stock wiper wiring, and the modified wiper wiring with details about the kit itself and how I mounted it at:
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I can't confirm that it would work with other wiper wiring versions, but a glance at the three flavors of wiper wirings posted at Speedy Jim's website
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suggests that this modification will work with the steering column-mounted 12V, 2-speed version without any modification. I reckon that it could be made to work with the 6V 1-speed version with a little rewiring, and replacing the 12V relays on the kit board with 6V ones.