Above, you'll see the schematic for a simple EFHW tuner for the popular 40- and 20-meter CW bands. Dan Tayloe, N7VE; Charlie Lofgren, W6JJZ; Bill Jones, KD7S; and David Bixler, WØCH; share design credit for the tuner and LED-based SWR bridge.
(For an enlarged view, click on the images.)