SV: [AMPS] Network analysis of suppressors

[measures]

>
>> Tom you said:
>> 
>> "If the tube has enough voltage breakdown to handle the 
>> fundamental RF voltage without problem, we can be sure it will 
>> handle almost any spurious oscillation."
>> 
>> 
>> Is this really true? The unloaded anode rf voltage swings down in an amp
>> that oscillates with a parasitic and may hurt the cathode. 
>
>Well, anything that can be done at 200 MHz can be done at 1 MHz.
>
>The tank Q is higher at HF than it is at VHF in a typical HF PA, 
>and the HF stuff dominates the anode current. Not only that, anode 
>load impedance is generally higher at HF than anyplace in VHF.
>
>You can bet if the tube insulation fails at VHF when the load Z is 
>nowhere near as high as at HF, it will also fail at HF where peak 
>anode voltages can regularly exceed 1.8 times the dc supply 
>voltage. 

Not according to worst case tests performed on the SB-220. 

>Under conditions of mistuning, it can be several times 
>supply at HF because tank Q goes into the dozens or higher.
>
>This parasitic stuff is almost a fetish!
>
Would you like to discuss your assertion that the resistance of nichrome 
wire increases with a decrease in frequency?  

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