As I understand it, the formulas are based on bare wire, so if you use
insulated, you should take into account a little shortening. That was
the only point being made, I believe.

You do want to make it about 5% shorter if you use insulated wire...I built my
full wave 80 meter loop out of 13 gauge copper clad steel wire with a
polyethylene insulator...and it turned out to be too long...I wouldn't figure
the 5% in the equation, you can always trim the extra off.

Steve
kb8viv