[Prev][Next][Index][Thread]

# RCR Filter question, LTR question

```Hey Guys,

I am using the typical Fritz RCR filter with (4) 5K resistors and (2)
1000pF caps.
I am using (2) 12/60 NSTs in parallel, so I assume that I have 120ma.
This works out to .120^2*5000 = 72 watts per resistor.   I really hate
to waste 4*72 watts on heating the resistors...

1)  I have a basic understanding the formulas and schematics for simple
RC filters, but I know that I'm missing some of the details on the RCR.
Other than adding to the overall R of the filter, what do the R's on the
NST side of the filter do?  Does the formula for the high freq cutoff
still work in this case, i.e.  F(h) = 1/(2*pi*R_total*C)?

2) Can someone please review how LTR systems draw more current from the
NSTs than resonant-sized caps?  I try to digest all the "theory" posts,
but somehow missed that one.  I remember that it deals with the energy
stored in the inductance of the NST secondary, but it didn't quite
understand it.

Thanks,
--
Ross Overstreet
Huntington Beach, CA
ICQ 20762411

```