Not in most cases, since turning on the attenuator significantly reduces the 
MDS (sensitivity) of the RX. IMDDR3 is the difference between the input RX sig 
levels that created the IMD and the MDS of the RX. It may increase IMDDR3 
slightly, or even reduce it, depending on which RX stages go into distortion at 
high levels first. But who wants a deaf RX that can not hear down to the noise 
floor of the band?

What turning on the attenuator (or having a poor sensitivity RX) -does- do is 
artificially increase the iP3 number, rendering it meaningless as a number for 
comparing different receivers which have -different- RX sensitivities for that 
measurement. Some manufacturers have gamed this number for years.

For best comparisons, receivers should be compared at the same sensitivity 
level. 

Eric
elecraft.com
_..._



> On Jul 25, 2015, at 11:17 AM, Joe Subich, W4TV <[email protected]> wrote:
> 
> 
> On 2015-07-25 2:04 PM, XE3/K5ENS via Elecraft wrote:
> > Apples and oranges.
> 
> Nonsense.  The IMDDR3 of a conventional transceiver will improve
> significantly if one turns on the attenuator.  Reducing overall
> input to the Flex series 6 to keep the level below the ADC limit
> is no different than adding an attenuator to a conventional
> transceiver.
> 
> 73,
> 
>   ... Joe, W4TV
> 
> 
>> On 2015-07-25 2:04 PM, XE3/K5ENS via Elecraft wrote:
>> Apples and oranges.
>> 
>> The K3 is still no 2 with the 200 Hz 5-pole filter.  You just can no longer
>> buy the radio with that filter.
>> 
>> I have always found it a little strange that Sherwood never stated that
>> the filters used in his test were optional on the K3?
>> 
>> If the K3 was tested with the stock filter it may make it into the top 10.
>> 
>> Don't get me wrong I have a K3S on order.  I'm just looking at the data.
>> 
>> 
>> 
>> --
>> View this message in context: 
>> http://elecraft.365791.n2.nabble.com/200-Hz-5-pole-filter-tp7605299p7605322.html
>> Sent from the Elecraft mailing list archive at Nabble.com.
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[email protected]
>> 
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [email protected]
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[email protected]
> 
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [email protected]
> 
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[email protected]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [email protected]

Reply via email to