TC-14E II / Minimum Aperture Signal Post

Hi folks -

I just received my first Nikon teleconverter ... the TC-14E II. I have a question about a component the literature identifies as a "minimum aperture signal post".

Is that component supposed to be loose (to move freely), or should it move with some resistance (like to have a spring attached to it)?

I will be coupling this TC to the Nikon 300mm f/4. Can someone clue me in as to exactly what this "minimum aperture signal post" does. The name is pretty obvious - just want to understand it better.

Thanks!

Kevin

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Kevin Childress