Bands 6-10 (Roman numerals VI-X) can be read across the top of this second calibration chart located next to the first calibration chart on the top of the E381S HF receiver. The calibration charts were used for coarse/rough tuning. The desired
frequency was found on one or the other calibration chart, the required coil was read at the top of the column, and that coil was selected using the coarse tuning step (band) switch.
-Photo by Bruce Culp
-Photo by permission of www.Horst-Beck-Collection.com