WOW!! I had no idea that story connected to Norcal and Wilderness radios! I have a couple of their kits and love them! Especially that watt meter. What I'd like is a new kit especially made for the worthless heathkit HW-7. Imagine something fitted or maxed out for that large box but using mostly the OEM appearance.
Wayne's comment about a future terminal connector accessory for the whip mounting jack inspired me to make a crude EZNEC model of the KH1 with 4' whip and 13' counterpoise. For this configuration, the value of loading coil inductance at 14mHz is about 10uH. With the counterpoise length and loading coil kept constant, I found that about 10' of vertical wire will resonant at 10.1mHz, and about 30' at 7.1mHz. Of course, a vertical 30' wire may not be practical, but the far end could be attached to a 20' sotabeams pole or tree, at about a 45 degree angle. If you double the counterpoise length to 26' and keep the loading coil constant, then the antenna wire length shrinks to about 16' for resonance on 7.1mHz.
That RF near field mode on the KX2 was going off last weekend at the park with the club when the next guy was using FT8 @100w. I heard the audio lower and saw “RF” come on the screen and said “WOW”, that’s neat.
