Thanks, Dave! Lot's of great info. I just bought a mint GD-1B in the
original box with 7 inserts. I understand what freq range the 1st 5
inserts do as they are marked and there is a picture in the manual.
Problem is the last two inserts - they have a lot of wire (looks like
AM antenna micro wire). One has 1 coil of wire, the other 2 coils.

Unlike the regular coils, these are wound inside the plastic form
and sealed. Any idea what they are for? Is that the 341-A coil set?
How do I use them (what range)?

Thanks again....

Ken KG0WX