Regarding Nox/EMI, I've run into two scenarios now where EMI was unbearable at anything over 19 sensitivity and switching to a stable single frequency allowed me to run the sensitivity up to 25 with silence. One was next to a radar tower where I had to use 15 kHz and up, which was silent. Second was this morning around a water tower, which was equipped with some sort of radio dishes or something, where again 15 kHz and up was silent. Multi-freq was unbearable, even after noise cancel at both. Just shows me that in those rare instances where EMI is crazy, you still have options to run high sensitivity, if needed, with the Nox. I mentioned it before in another thread, but I would love to see an update where we can omit frequencies vs using all or one. This could be extremely handy.
Calabash, out of curiosity you should see what frequencies are effected at your test garden by cycling through them at higher sensitivity.