Marbelite M20 Electromechanical Controller
This is the 5th controller in this collection. It is a 2 phase controller which means it can control a regular intersection with North South traffic and East West cross traffic. It is not set up to do pedestrian signals. There is a video of this controller available on the video page.
This controller has just one dial as seen below unlike the EF-70 which has three.
The cam shaft in this controller is similar to EF series controllers in that there are finger contacts that raise and drop by cams that have lobes broken out. This controller also makes a kerchunk noise similar to that of EF series controllers.
This page was originally posted on 11-27-2008.