Using FIRST Choice encoders on Toughbox gearboxes

I’m hoping to use the AMT103-V encoders we recieved from FIRST Choice on a Toughbox Nano gearbox. Unfortunately I am very unfamiliar with using / properly mounting encoders. I am guessing that the “mounting pad” seen in the product picture could bolt onto the back of the Nano gearbox so that the output shaft fits nicely. I assume that the hole pattern on the encoder does not match the hole pattern on the back of the Nano, but I can’t find the specs, does anyone know?

Will the back of the output shaft fit into this encoder? I can’t find acceptable shaft sizes for the encoder in the documentation.

Also, I’m assuming the required data cable doesn’t come with this. Is that correct? I’ll need to know if I should order those as well.

Sorry for coming into this blind, I just want to be absolutely sure before putting money down :o

The AMT103-V comes with a kit with many different size shaft adapters. The snow colored one (I assume they mean white) will fit the 1/4" shaft of the nano gearbox.

The mounting pattern is not the same as the E4P encoders so you will have to figure something out. Either drill small pilot holes and use plastite screw to fasten it down to the pad or use strong 2 sided tape (3M VHB). You may want to fab an alignment bushing to do this to ensure proper alignment, although if you are careful you should be able to skip this step.

I am not sure whether or not it comes with a cable, but I would doubt it. We were planning on ordering these using our $50 FIRST Digikey credit.

I was considering directly mounting it to the gearbox, but this is an even better idea. If we mess up any drilling into the pad, they are only 4 bucks to replace. I think I will buy a couple extra pads and plans to mount the 103’s to the pads and the pads to the Nano.


What are the pads you are referring to? Where can you purchase them?

He’s probably talking about the am-0208. It has holes intended for the US Digital E4P encoders. You can mount them to a Toughbox, and you can mount the CUI AMT103 base on them if you add more holes in the proper places.

We’re finding that the am-0208 is just a teeny bit thicker than we woud like, but it works. The mechanical group is learning the skill of mounting the encoders, and the programming group is learning how to modify the Talon SRX example so that it does what it’s supposed to.

Yeah, that is what we are working on now. It looks straight forward, and I like the ability to have spare pads to mount to instead of needing to mount into the gearbox shell.