[Elecraft] Noise from LEDs

[johnpierce]

My kitchen, under cabinet lights, are LEDs.  With those lights turned on my
noise floor changes from -128db to -102db.  If the circuit is changed to a
different phase the noise improves by 6db.  All of this at 7mhz and other
higher bands.  Needless to say the AM broadcast band is highly affected by
the LEDs.

 

Placing a type 31 core with three turn of the AC line feeding the LED power
supply and a clamp on 31 core on the LED side of the power supply provides
no improvement!  I do not have an oscilloscope to look at the waveforms.
But given what I have done, why is there no improvement?  I was following
recommendations provided by NK7Z.

 

AD2F,  John