Craig says:
>it offers 60 db attenuation of the second harmonic. It offers
much >greater performance than the 7 element chebyshev design
You get about 30dB of second harmonic attenuation in a pi with Q =12,
another 30dB is all you need at the most. This means a fairly simple filter
will do....such as a n=3 Chebyshev with .01dB ripple.....that's 2 caps and
one inductor, or 2 inductors and one capacitor. Which one depends on the
availability of the caps - they'll have to handle a lot of current, and for
1500 watts, really need rating at 500v AC at the frequency of operation.
(More if you use two inductors and one capacitor)
73
Peter G3RZP
--
FAQ on WWW: http://www.contesting.com/ampsfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|