Is my coil bad?

[Qwix]

X-Terra 70 with the 9 inch concentric MF coil.

I set up a test garden to practice my pinpointing and noticed this. Every target will give me a tone when the coin passes under the outside ring of the coil and then another tone when the coin passes under the inner ring, no tone when the coin is under the center of the coil. Now here's the strange part (at least to me) the tones only sound off under the left half of the coil. No response at all from the right side of the coil.

Is this normal?

 

[Old Longhair]

Are you running any DISC, or are you in All Metal? Does the machine null or have a break in the threshold when you come at the target from the left?
How deep/shallow are the targets in your garden? Where is your Sensitivity set?