>Rich says:
>
> > how come all PA's don't show spurious non harmonically related
> >>outputs?
>> >
>>? HF PAs do.
>
>
>Not this side of the pond, they don't - unless the design is crap and they
>are oscillating.
? With the tube not in a state of regeneration, a spectrum analyzer can
see trains of damped vhf waves coming from the anode-resonant circuit.
The only requisite is that DC current transients be passing through the
resonant circuit. The same phenomenon can be simulated on the workbench
with a vibroplex key, a vhf resonant circuit, a resistor and a LV source.
> Nor in the ARRL lab reports published in QST.
? The ARRL Lab tech. who tested the Ameritron AL-1200 told me that he
observed intermittent tank spitting that he suspected was caused by an
intermittent parasite. This information was not published in QST.
>
>> One can put a conductance of10mSiemens in parallel with a susceptance
>>
>And it's still a conductance 10mS or a resistance of 100ohms. The only way
>to increase the resistance (or decrease the conductance) is to put a
>negative conductance in parallel.
? It might be worthwhile to look over Wes' measurements.
>Since negative conductances require active
>devices, it doesn'r apply. Mind you, if you can find a passive negative
>conductance, your fortune is made...........you won't need PG & E.
>
>>>Rubbish! That's the definition of admittance - the reciprocal of impedance
>> >
>>? Try it. Take heed that ye beware of the snare.
>
>No snare if you do your sums right.
>
? "nothing is as easy as it looks"
>
- cheers, Peter
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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