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Nouveau 75 Distorted Audio

Bill VanKirk
 

I just completed a Nouveau 75 kit. Everything seems to function as it should however the receive audio is distorted to the point you can not understand the receiving station. I have completed all the usual checks for parts placement etc. and as far as I can tell everything is correct. I do not have the skill to work with SMD parts. Would someone from the 4states group be willing to take a look at this for me? Please email me direct with any questions etc.

73
Bill
W0PT

nm0s_qrp
 

This rig uses a TA7642 IC for the AM detector and AGC.  It combines many functions in a three-pin package.  It is also known for its distinctive audio characteristic, as builders of the Murania can attest.  The audio quality is somewhat determined by bias levels.  Much of the harshness of the audio can be rolled off in the speaker driver bu adding some additional capacitance to C12, in the 0.001 to 0.01u range.