GENIE 3850R works very well with my GENIE receiver #315390R2 that I have operating an old Chamberlin opener.
The receiver was not included in the installation instructions but they were the same as the first (A) instructions you sent.
You probably know all this but just in case not I thought I would comment anyway.
Thanks
I needed a logic board for my 3800PLD jack shaft garage door. I was told by my local garage door service center that I would never find a working logic board. They told me if I did find one that it was probably too old from sitting on a shelf somewhere and probably would not work either. I know they wanted to sell me a new motor but for the high cost of a new motor I was willing to take a chance on the new logic board. It arrived quickly and in a box that looked new. A good friend installed the new logic board and now my garage door openers and outdoor key pad work great. Also, my garage door used to shutter about 6 inched from closing and now it closes all the way very smoothly. Again the local garage door service center told me a year ago that the shuttering motion was because I need a new motor. Thanks so much for a great product and great service!