[Amps] Low Pass Filter capacitor ratings for 1.5kw level

[Tom W8JI]

>    OK, after looking on the internet and doing some 
> reading I decided to use the low pass filter values in the 
> ARRL RF Amplifier Classics book I've got (not the greatest 
> book but they do have 2 projects with LPF values for all 
> the bands).  Problem is that both of these LPF filters are 
> for low power projects (one design uses 6 filters and the 
> other uses 7 filters to cover all bands from 1.8-30mhz). 
> I plan on using the same values but higher power 
> components.
>    Question: For C1, C3, and C5 in each filter what would 
> be recommended voltage ratings for either silver mica or 
> doorknob to get a 1.5kw (plus headroom) rating?

Mike,

The biggest worry is generally current rating, not voltage 
rating. A secondary worry is impedance of leads if you 
intend to reject very high frequency harmonics.
The caps must of course have to have enough voltage, and the 
voltage can be higher than the input and output voltage 
depending on the exact filter design.

You should model the filter if you are not comfortable doing 
calculations the long way.

73 Tom