[hpsdr] Odyssey Active QSD Rev. A Schematic

[Alberto I2PHD]

Steven Bible wrote:
> 
> Gang,
> 
> Here it is, revision A version of the schematic using Ahti's active QSD circuit connected to a TI Codec.
 > The TI codec will be connected to a dsPIC33FJ256GP710.
> 
> You will notice that I added some extra components and labeled them with ? values. 
 > These parts are just a guess as to weither they are needed or not.  I thought to place the foot prints for 
prototyping purposes.
 > However, I do know the circuit well, so I'll allow the group to comment.  If they are not needed at all, I'll 
removing them.
> 
> Comments please.
> 
> - Steve N7HPR

Maybe mine is a naive comment, but the two opamps have their inputs biased at 2.5V and the supply voltage is 5V, 
single-rail. Given that good sound cards can happily accepts up to 4V and more of signal, isn't a design that limits its 
output to 2.5Vp incapable of fully exploiting the dynamic offered by the sound card itself ?
Wouldn't a ±15V as supply voltage be more adequate for an uncompromised design ?

73  Alberto  I2PHD


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