Conventional transformer does not activate bell or whistle

Well, the TW transformer has no bell function, so it won't activate the bell.

That makes sense but I was hoping the transformer would at least blow the whistle.

It should blow the whistle if the whistle control is working correctly.

The whistle control on postwar transformers go through two states as the control is operated.
First a rectifier (diode) and booster winding is cut into the circuit, making the power 1/2 wave DC.
Then a rectifier is added in parallel to the rectifier to make the power AC with some DC bias.

It's not a solution, but the modern era unit usually will sound with the control in the first state.
But as the lever continues to move to it's final position, the unit goes silent because there isn't enough DC bias.
This is because the amount of bias is dependent upon the load, and modern era locos often don't draw enough.

One solution is to add more load in the form of incandescent light bulbs connected to the track power.
Sometimes running a longer trains makes the train work harder, and draw enough power.

As far as I know, whether it's the horn or the bell is dependent upon the direction of the DC bias.

There is always the possibility that the whistle control on your TW is out of spec, and not generating the DC / DC bias correctly.

Thanks, that is good info. This transformer works perfectly with traditional Lionel. Looks like we need to get a modern unit to run a modern unit.