Understanding Digital Radios

Alan WA9IRS writes: 

Hi Bill,

Thought I would drop you a brief note.  I have been catching up on my listening to past issues of Soldersmoke podcasts and was particularly interested in the discussion between you and Pete concerning the simplicity associated with non-digital, integrated circuits and microprocessors and all of the rest of the very small miniaturized circuit elements.  You rightly pointed out that you desired (along with a lot of the rest of us) to fully understand what was going on in a circuit and for that reason desired to maintain the simplicity of transistor and discrete components in your design and build projects. 

 I agree with you completely but offer the alternative to the simple circuits in the form of the attached simple diagram of the signal flow path in a digital radio. I found this some time ago in a digital electronics magazine and thought you and Pete would find it interesting.  Perhaps this might be something to spring on Pete on 4-1-2018.

Take care and thanks to both of you for many pleasant and thoughtful hours of enjoyment listening to Soldersmoke!

All for now, 73,

Allan,  WA9IRS

My response: 

Thanks Allan, Very illuminating.   It is all clear to me now.   I feel so much better.  FB OM.   73  Bill