[Elecraft] K1 Audio Problem after fitting KNB1 Noise Blanker

[Ray Spreadbury]

Hi All

I've just completed the Noise Blanker to retrofit into existing my 4-band
K1, # 3020. 

Part of the installation is to remove C22 from the K1 RF Board & fit the
female 8 pin connector at J1 which seemed to go OK. 

I then fitted the KNB1 to the K1 & went through the initial tests. There was
immediately a fairly strong audio whine on all frequencies, all bands but
there were no error messages & the menu for the NB (Off/Hi/Lo) worked with
no problem. 

The whine is present with/without an antenna connected and after removing
the NB board, the whine is now still present. CW signals can be tuned in
fine so the problem appears to be just in the audio.

Ant ideas please guys?

73

Ray, G3XLG