Antenna adjusting

[Pro-95]

Ok we've all seen it. Someone is adjusting the rabbit ear antenna on the old TV and everyone yells hold it right there.... and as soon as they let go, no picture.

What is going on here and why can the signal never be as good as if someone is holding on to the antenna?

Surely the body although conductive is also resistive. Is this a capacitor effect like gamma matching?

 

[loumaag]

Surely the body although conductive is also resistive. Is this a capacitor effect like gamma matching?

Umm, short answer is yes (sort of). An antenna is a resistive load to a RF source (receiving is the same theory but easier to explain in reference to Tx'ing). If the antenna did not present a load to the source, nothing would be radiated and nothing would go out into the ether ( :roll: ) as they used to say. The RF source circuits expect to see a resistive load of a certain value at the output of the circuit. The closer the load is to the expected value, the better the radiation.

Antenna theory in free space is tough enough to understand, when you start introducing real world items into the picture (couldn't resist) you get that, Okay, don't move effect. See the response I sent you on the Log Periodic thread.

 

[LarrySC]

Another idea: Some people are better at being an antenna than a human being.