Anyone know if there are any internal adjustments on a TA-300?

[Tony (Orlando, FL)]

Reason I ask is I met up with a fella that has two and one of them is significantly more sensitive than the other. He bought them both new.

One does an outstanding job, while the other one is so so.

There must be a course sens adj that is not set the same internally as both coils were swapped as well as the batteries and the more sensitive unit still stayed more sensitive with both coils.

I am hoping to find out if there is some control inside I can share with them.

Anyone know?

Thanks,
Tony