On 21Mhz rather than a band pass/high/low filter what about 23mhz
trap(s) also called notch filter. Even high Q should be wide
enough to cover whole 23.8 to 23.55Mhz.?? Similar for? 24Mhz??
needs to cover 20.17 to 20.01Mhz
Cheers,
Will
ZL1TAO
On 23/06/18 13:33, Jerry Gaffke via
Groups.Io wrote:
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Table two of the
arrl.org filter reference shows that the 21 mhz bandpass filter?
has 15db of attenuation at 28mhz, that's 7mhz away.
We need something like 20 dB of attenuation at 2mhz away.
As Allison says, that's a tough nut to crack.
And I have my doubts about the filter I pointed to.
Jerry
On Fri, Jun 22, 2018 at 04:31 pm, Gordon Gibby wrote:
Forgot to put the link.
?
?
