>Why are the most of you talking of HV resistors ???? Be realistic and
>that this is to avoid the current during arc.
>I Always put those current limiting devices at the LOW voltage potential.
>A few ex. could be : at the center to GND of the HV trafo,
> In the - HV lead just between this and
>This is GD construction design, and you get the exact same kind of protection
>AND avoid HV resistors or HV fuses.
That's not true - and it can be dangerous!
If the resistor is where you describe it, in a +3kV supply, a current
surge from the HV+ rail will push the center-tap towards -3kV with
respect to chassis. The voltage across the resistor is EXACTLY THE SAME
as if it was in the HV+ line.
Also the center-tap is designed to be grounded (or very close) so the
insulation at that point may not stand 3kV.
There is a range of commercial amplifiers where they do this. The glitch
resistor and a 1-inch mains-type fuse are in the negative lead, just
mounted on the PC board with all the other low-voltage components. The
HV-minus connection is ordinary hookup wire, and it goes back to the
bottom of the capacitor stack through an un-insulated hole in the
chassis. This is all FB when the amp is operating OK, and it saves the
extra cost of mounting a resistor and fuse in the HV+ rail. But what
happens if there's a current surge, I dread to think - it could side-
flash to anywhere!
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
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