Is there anyone left who is familiar with calibration of a Millen 90651 grid
dip meter? ....

The Millen grid dipper was never a calibrated ,or accurate device, to
get an accurate reading ,tune a receiver to the desired frequency and
set the dipper to the receiver ,You will be anble to get "in the ball
park" Good Luck W4PQW

Hmmmn. Never calibrated?

I have a chart from "James Millen Mfg. Co., Inc" dated 1-31-50 and
titled "Calibration of low frequency inductors for James Millen
#90651 or #90661 Grid Dip Meter".

--Myron, W0PBV.
--
--Myron A. Calhoun.
Five boxes preserve our freedoms: soap, ballot, witness, jury, and cartridge
PhD EE (retired). "Barbershop" tenor. CDL(PTXS). W0PBV. (785) 539-4448
NRA Life Member and Certified Instructor (Home Firearm Safety, Rifle, Pistol)