[angrygoat]

Excellent that there is accessibility support, but at what range can people pick my calls up – especially with a directional antenna?

[commonjcb]

Approximately the same distance as a good microphone can pick up the audio anyway. Read about near-field vs far-field:

https://en.wikipedia.org/wiki/Near_and_far_field

[Johnythree]

Good luck building a directional antenna for the AM broadcast band (especially a portable one).