[Elecraft] Analog vs. Digital Front Ends

[Alan]

 > Someday they will be, and many of us will be using them.

I think it was back around 1993 that there was a discussion on the 
Internet about using a wide-band ADC to replace the front end of an HF 
receiver.  I commented then that you just couldn't get good enough 
performance with affordable ADCs available at that time, but someday you 
might.

Time marches on and now ADCs are available that give usable performance 
at a reasonable price.  They still can't compete with a state-of-the-art 
receiver like a K3, but they are as good as many analog radios of a few 
decades ago and are quite reasonable for casual operation or even for 
contesting or DXing if you don't have a very high-signal environment.

So how long before ADC technology catches up to the K3?  If Moore's law 
applied (doubling of performance every couple years) it wouldn't be 
long.  Unfortunately Moore's law applies mainly to digital circuitry but 
the key parts of an ADC are analog (the "A" in "ADC").  Unless there is 
a big theoretical breakthrough in ADC architecture, I think we still 
have some years to wait.

Alan N1AL


On 09/15/2015 08:49 PM, Jim Brown wrote:
> On Tue,9/15/2015 5:48 PM, Walter Underwood wrote:
>> This might be an orthogonal opinion, but I think it is awesome that
>> high-end direct sampling receivers are competitive with mid-range
>> superhets.
>
> But they are NOT competitive in strong signal environments! That's the
> point of this discussion -- the measurement system must give them a
> 10-20 dB handicap to make them LOOK competitive.
>
> Someday they will be, and many of us will be using them.
>
> 73, Jim K9YC