Re: Trial to control CW power (and reduce harmonics as a result) by unbalancing the 2nd mixer #ubitx

Jerry Gaffke
 

Signal level into the D1,2 mixer can be a bit higher than it is into the D3,4 mixer
when transmitting SSB.  But not by much.

Assume the D3,4 mixer has a signal loss of 6dB, the 45mhz crystal has a loss of 4dB,
and that the 2n3904 based v3,v4 uBitx 45mhz IF amp has a gain of 10dB.
(Gain is less than the designed for 16dB because the 2n3904's
can't give that much gain at 45mhz.  I have no idea what v5 does.)
We wind up with the same level of SSB signal into the D1,2 mixer
as we had going into the D3,4 mixer.  


On Thu, Apr 18, 2019 at 08:15 PM, John (vk2eta) wrote:
Yes that gives me good reference points. So assuming the clocks #1 and #2 are at the same level, it looks like after this mod the signal at T2 (3,5) could be around 10 to 16dB too high.

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