Finally got this figured out, I think. The cheaper mic has fewer useable channels and is a line of sight mic....the transmitter can't get too far away from the receiver.
The EW 100 series is radio frequency with more useable channels and no line of sight issues. I got quite a deal on the E935 and EW 100 series so glad I went with the EW series. The EW 100 series is an 835 capsule but the capsule can be replaced.