Norman Hockler wrote:
>
> Wondering about the harmonic attenuation of a Pi L tank vs a standard
> Pi tank followed by a good quality low pass filter.
>
> I am interested in building an amp using a tune and load cap with a good
> roller inductor in between to eliminate the band switching mess and adding
> a good low pass filter.
I presume that means you're thinking about a single TVI-type lowpass filter.
Such filters have cutoffs around 30 or 50 MHz. That would do nothing to reduce
the low-order harmonics of the low bands -- for example, all harmonics of 1.8
MHz up to the 16th would fly right through!
I suggest a PI-L network using the roller inductor with a fixed L switched in on
160 and 80 meters.
73
Vic K2VCO
Fresno CA
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