[Elecraft] Effect of "Level" Control

[Doc K0EVZ]

Gang:

I just accidentally switched the "Level" Control from "LO THR" to "HI
THR".....and WOW what a *huge* difference in background noise.  All of a
sudden the desired signals are just there, with almost no band noise.  When
I switch back to "Lo Thr" the noise level comes up dramatically and the
signals seem to be about the same as with the other setting.  Wow, all of a
sudden the band is very much quieter.  This effect is there--the quieter
background--whether the NB is on or off, as far as I can tell.  This is not
a subtle difference, IMHO.

What has happened here?  I have read the manual on page 87, but am still
confused.  Gotta tell ya, sure wish I had stumbled on this setting change
before.  Have apparently been listening to loads of band noise for years
[g].  Anyway, can anyone enlighten me on this?  Thanks in advance.

73,
--Doc/K0EVz