Large Scale Central

What are these 2 items?

What are these 2 items? They are connected to the Soundtraxx sound card in one of my Heislers that TOC installed many years ago? What do they do? They were at one time hot glued to the rear truck right next to the wheels however, they have come off. I’ve tried to hot glue them back on but I believe that the center drive shaft knocks them off when the Heisler runs through the 4 LGB 14000 curves on my indoor layout. I’ve also tried to super glue them back on but again, they don’t stay put.

They look like reed switches of some sort (maybe a hall effect sensor if there are no magnets), probably for the sound card chuff.

Yup. Reed switches for track magnets to activate sound bells and whistles. And in some instances to throw a switch (turnout) for a trolly back and forth, etc.

I think Bob is correct and there should be a small magnet(s) stuck on the back side of the wheel that can pass it with each rotation. Maybe the magnet is missing.

You can probably trace the wires and work out which connections on the sound card they are wired to. Either chuff, whistle or bell.

From the fact that they are right next to the wheels, chuff seems likely. But I don’t know why you’d have 2 of them.
Check the back of the wheel for small round traces where the magnets were glued?

As far as keeping them in place, I usually clamp them, as shown in my r/c thread.

See if the screws holding the rear chassis cover are close enough so that you can put a strip of brass around them.

I heard back from Dave Goodson. He confirmed they are to trigger the whistle and bell. As far as clamping them to the Heisler rear truck, I don’t see anyway I could accomplish that.

Dave did mention that I need to be very careful with glueing them to the front of the truck to not glue the bottom of the truck so I can still take the bottom cover off.

The issue with them coming off is that they are hitting the drive shaft on tight curves when glued to the front of the truck. I wonder how close they need to be to the track magnets. Wonder if I could afix them up above the truck?

Not much further than 1/4" in my experience.

Timmy, my comment on my prior post was to check the screws holding the bottom cover. Often you can take one out, slip a piece of brass with a hole in it, and replace and re-tighten it. May need a longer screw, but it can be done.

You’ll have to make up a piece of brass plate that fits over the screws and then over the relays. Probably an “H” shape?