You can do it that way if you don't want accurate information. When a bag of corn seed costs over $300 (that is a 50 lb bag) you can't take anything for granted and every row is monitored. Plus with my electric planter drives I vary population on a row by row basis so it gets pretty important then too.

www.electricplanter.com

The sensor detects each seed passing through the seed tube after is falls from the seed plate on its way to the ground.

Quote Originally Posted by EarlyBird2 View Post
I thought that on a seed drill all of the disks rotated at the same speed and the spread rate was a simple calculation involving the number of slots and rpm. This would mean that only one disk needs to be monitored to calculate the spread rate. The complication is detecting missed seeds for which each disk has to have a detector. So the question is what form does the existing detector take does it count seeds or missed seeds? I would have thought the latter and if that is the case then the application becomes easier.