[Kenwood] Aligning Noise Blanker on TS-940

[Don Winn]

I have two TS-940 and the noise blanker works great on one and has no 
effect on the other.  I'm betting someone has made some adjustments to it 
and  it's mis-adjusted.  I bought it used several years ago.

The service manual says to align the noise blanker, use a  Noise Generator 
which generates noise containing harmonics beyond 30MHz.

Is there a simple circuit that will generate a signal or do I need to pull 
a spark plug wire on my car and let it arc to ground?

Has anyone had any luck with using powerline noise as the source?  That's 
the main noise source I need to reject.

Don  AF4Z