Continuing the discussion from New Elecraft Rig: KH1 (Part 2) - #100 by LZ1WF.
Previous discussions:
Does anyone know why the KH-1 has not been designed to work on the 28 MHz band as well?
73 Karel
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I’ve heard Wayne saying on some interviews that it’s a compromise. They couldn’t fit more bands in this small design considering all constraints such as having a tuner and keeping the same batteries as in the KX2. Wayne also claims they built the smallest ATU ever to make it fit in the KH1.
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Thank you, that makes sense.
The main reason to choose exactly these KH1 bands, in the words of Wayne, N6KR:
As for the KH1, its five bands must be adjacent to each other given the band-pass and low-pass topology we used.
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So the bandpass and low pass filters span two or more adjacent bands to minimise parts count (build cost), size and weight. 40 to 15m is a 14MHz span (21-7). Adding 28MHz would make it a 21MHz span, must have been to much of a stretch. And it would have added parts to the ATU as well. Bit of a pity, but they’ve done a remarkable job as it is.
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