On Friday 17 May 2002 10:17, Tom Rauch wrote:
> > >Ahh. That's the best explanation I've heard for what causes
> >
> > sub-harmonics.
> >
> > >Thank you.
> > >
> > >Now where's the nonlinearity in the solid state PA's? from the
> > >nonlinear junction capacitance or the nonlinear ferrites?
> >
> > In the devices, I think. The effect happens in VHF PAs without any
> > ferrite in them.
>
> Are you sure about that Steve? How often do you see it?73, Tom W8JI
> W8JI@contesting.com
Sorry for the delayed reply.
Haven't seen it much since I moved away from Milcomms. VHF handheld and pouch
radios used to drive us nuts - the output stage was driven hard to maximise
efficiency, then subjected to 3:1 VSWR in operation.
I'm not saying that division was certainly the starting point for what we saw
- it's quite possible that the spurious started life as an oscillation that
ended up 'locked' at f/2, 3f/2 etc.
Steve
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