Re: RF Power #chat
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I don’t understand the 30 dB of return loss in the stopband. These filters should reflect energy back to the source away from the passband, and how come the reflected plots have the same shape regardless of which frequency band you are testing? If you spread the turns on the 20 m filter, does the passband response change? Use the reflected S11 plot to tune the filters (once they are correct) – much easier than using the S21 plots…
From: QRPLabs@groups.io [mailto:QRPLabs@groups.io] On Behalf Of Andrew Lenton
Sent: Saturday, September 2, 2017 12:52 PM
Subject: Re: [QRPLabs] RF Power #chat
Just Rechecked that post 11th Aug, the LPF was not the QRP kit version, but one I made earlier, for the Raspberry PI, which does work rather well.
On 02/09/2017 20:14, Andrew Lenton wrote:
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