The B&W 850A was designed to be used 80-10 meters I modified this one for use on 160-10 meters. Inductances are as follows: 10M .69 uh, 15M 1.07 uh, 20M 1.75 uh, 40M 4.12 uh, 80M 9.2 uh, 160M 18.4 uh (with 4 1/4 turns of 3033 miniductor added). this coil was designed for a higher RL than my 2300 ohm ( .85 A & 3000V) so the original  13.5 uh almost covers down to 160 instead  of 80. The 3033 coil adds another 5 uh. I had a spare B&W switch contact in my junkbox for the 80M tap.

40M tap moved 2 turns, an 80M tap added 3 turns beyond old 40M tap (1 turn shown here, later changed to 3)
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