I found that some cases of high SWR on the output side the voltage on the
detector diodes killed them at 20W but not at below 15W. For matching 3:1
or less it was not an issue. Since most of their low power radios are 12W max
its rarely an issue. Excellent match to my Argonaut 505 and FT817.
However, I've used it to tune end fed half waves, and 8ft whip at 20M and I
firmly believe its able to tune a nail at 40M or at least try. Its quick about it.
As kits go it was a fun build. Lots of toroids!