[AMPS] Henry 2K2

[Rich Measures]

>
>Picking up on one of Rich's remarks:
>
>>Henry's glitch-R in the neg. HV 
>>lead is a mistake.   A glitch R should be added to the pos. HV circuit.  
>
>It doesn't really matter which end of the HV circuit the glitch resistor
>and HV fuse are - unless the designer thinks that putting them in the
>negative return rail requires less insulation. In fact it requires
>*more* insulation, because a "crowbar" short from HV+ to chassis will
>tend to push the return rail down to *minus* the normal HV. 

>To avoid breakdown, the negative rail and the negative end of the
>capacitor stack therefore need to be insulated to the same standard as
>the positive end.
>
€  The sticky wicket with putting the glitch-R in the neg. hv circuitry 
is that the filament transformer/cathode circuitry must be insulated for 
several kV.  However, allowing the cathode to rise to several neg. kV 
during a HV+ short to chassis is likely to cause an arc to the 
grounded-grid.  Thus, it is my opinion that it matters which end of the 
HV circuit the glitch-R is in.  

-  cheers,  Ian


Rich...

R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures  


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