[TenTec] Explanations of the Different Types of Filtering on Radios

[Will Jones]

There are a few of us who meet together every Wed. morning at a local restaurant to talk about ham radio and stuff.
Some are new hams. One asked this week a question which I think would be an interesting study in comments.
He asked, "I have an I.F. shift on my radio and I have read about what it does but don't really understand "what" it does. Also how does it compare to the other features I see on radios such as PBT, notch filters, RIT, DSP noise reduction and noise blankers. Without having a radio with these features on them it is hard to explain just what your signal will sound like when these devices are used.
So can anyone give us some ideas how to explain these different types and why we would want one and not another and why radios don't have them all on one radio. 
Bill, N4LB in TN