I was out and about running errands when I stopped at an oil change place along the Parkway here in Huntsville, which happened to be located right next to Firehouse Antiques. So I decided to wander around the antique store while my car's oil was being changed. Shortly before I was about to leave, I happened to spot some Harmon 12x24 inch lights from Madison Boulevard's crossing right outside of a pair of doors. After taking a look at them, I was about to head back inside when I spotted this bell, so I went ahead and bought it, thinking is was a WRRS Motor-bell. When I got home and opened it up, however, it turns out it was actually a WRRS 1203 bell, something I hadn't seen before! These bells, while they have a similar box on the back as a motor-bell, the box is used to mount a rectifier rather than to make room for a motor. Also, unlike motor-bells, which are designed to run off of 110VAC, these bells are designed to run off of 8V to 12V, in either AC or DC. However, if it's being run off of DC, the positive and negative wires have to be swapped from how they'd be positioned when running the bell on AC power. The bell is pretty much a standard WRRS bell for the most part for the rest of it, it appears.
It appears that there's a couple of differences that you could use to tell them apart without seeing the insides. First off is that a WRRS 1203 bell has a bolt sticking out of the back of the back, with no branding on it either. However, a WRRS motor bell, since it doesn't have anything mounted in the box, would lack this bolt and also has a branding on the back of the box. WRRS 1203 bells stop normally like other bells, while it sounds like WRRS motor-bells will have the bell slow down a bit as it stops, from what I can tell in this video:
WRRS motor-bells also likely wouldn't get use on crossings due to them requiring 110VAC power, while most crossings operate off of DC power. As such, I have a good feeling that most, if not all, of the WRRS "motor-bells" we've found in use on crossings may actually be WRRS 1203 bells. Anyways, here's the pictures and videos of the bell:








A "walk-around" video showing the various parts of the bell, and goes into a bit more detail about them (and when I think the bell was made):
The bell operating: