Rafal,
You're probably right, the impedance mismatch at the product detector is a good issue to look into. ?Check crystal filter response carefully before and after making any changes to impedance there, the shape will likely get better. ?Perhaps borrow the transformer scheme from the uBitx: ?/g/BITX20/message/22888? ?I'll likely be borrowing the entire uBitx design someday, addresses most of Allison's criticisms and gives multiple bands with a minimum of band specific filter switching. ?I' plan to use the uBitx with a resonant EFHW antenna tuner to limit out of band signals on rx, further reduce harmonics on tx.
Jerry, KE7ER
On Fri, Mar 17, 2017 at 01:45 am, Rafa? Lichwa?a wrote:
The bug found (in my opinion) is just wrong Zin/Zout attenuator between 3rd amp and product detector...
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