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Published 20 hours ago • verified publisher icon kamocat

PA tx and rx values

Open kamocat opened this issue 4 years ago • 2 comments

We need a set of values for the low-pass filter on the power amplifier board, as well as the band-pass filter for the receiver. A separate of values for each ham band is needed.

kamocat avatar Jun 27 '20 01:06 kamocat

I set up a simulation project in KiCad for testing filter values. I'm not sure about the drain capacitance of the BS170 or what effect the Miller capacitance will have, so it will probably need some tweaking.

kamocat avatar Jun 27 '20 02:06 kamocat

Cees (PE1DDA) mentioned this nice little calculator: htts://rf-tools.com/lc-filter/ It looks like a 7th order elliptic would completely eliminate our first harmonic, but a 5th order would fit well to our current design.

kamocat avatar Jul 18 '20 18:07 kamocat