All the Tamiya compatible apples have some level of functionality, but if you are fighting with a club, it's easier if you have the TBU.
At it's heart, you just need sensors, a cap, resistor and emitter. The one below is just some components installed in a Tiger I cupola. It has the exact functionality and range of the TBU.
https://www.youtube.com/watch?v=CQpSZzFiF6I