[Elecraft] Sherwood Receiver Test Data - K3S Added Today

[Barry LaZar]

Fred,
     When you have a 24 bit A/D and not looking at the entire spectrum, 
this should not be as big a problem as you imply, if gain distribution 
is correct.  24 bits should yield a great enough dynamic range to cover 
greater than ~ 95% of time; that last ~5% covers your friend next door 
with a KW or that thunderstorm over head. 24 bits also allows for some 
amplification to overcome the down stream noise figure that may be 
greater than ambient.
     On the other hand, the Flex uses a really high speed A/D, but it is 
only 16 bits, if memory serves. That architecture is far more sensitive 
to gain distribution. Those who have suggested that the Flex may have a 
problem with all the bits going to 1 in a stress environment may be very 
correct. IMHO: With the state of the A/D art as it is, I believe 
Elecraft has the better practical architecture. As soon as low noise, 
high speed A/Ds become available with greater than 16 bits, my opinion 
may change.

73,
Barry
K3NDM


------ Original Message ------
From: "Fred Jensen" <k6dgw at foothill.net>
To: elecraft at mailman.qth.net
Sent: 11/10/2015 7:32:56 PM
Subject: Re: [Elecraft] Sherwood Receiver Test Data - K3S Added Today

>Question from a mathematics major [whose parents wanted him to be a 
>EE]:
>
>In a direct-sampling receiver, how do you control the input level to 
>the ADC to achieve maximum available dynamic range without clipping at 
>the ADC?
>
>73,
>
>Fred K6DGW
>- Northern California Contest Club
>- CU in the Cal QSO Party 1-2 Oct 2016
>- www.cqp.org
>
>On 11/10/2015 3:58 PM, Steve Ellington wrote:
>>Looks like the K3S should be above the Flex because the Flex achieved 
>>2DB
>>higher due to:
>>
>>Footnote Y --- "This is a testing anomaly of a direct-sampling 
>>receiver."
>>
>>Congratulations K3S
>>Steve N4LQ
>
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