Can a ghost cause a voice activated transmitter to send a signal to a receiver ?

They are electrical charged and I don't know much about them but I would say probably

Here are some links you might like

Nature of EVP (http://www.aaevp.com/articles/articles_about_evp4.htm)

About Energy (http://www.aaevp.com/articles/articles_about_energy.htm)

It's all to do with energy... yes

Can a ghost cause a voice activated transmitter to send a signal to a receiver ?

No. A "ghost" is essentially a spirit, and a voice activated microphone uses audio power to turn on the transmitter. The audio is in the physical, not spiritual realm.

I am an electrical engineer and a ham radio operator who happens to have a voice operated microphone on my radio.