Richard Clark wrote:
"You make a loop."

There is a difference. The small whip has a high capacitive reactance.
The small loop has a high inductive reacvtance. Both have low radiation
resistance. But, the loop is more often used to determine EM field
strength. You just need the right "fudge factor" to convert antenna
voltage tto field strength or vice versa.

Best regards, Richard Harrison, KB5WZI