[Elecraft] Dual Pass Band

[Joe Subich, W4TV]

That information is based on input from K7AY (cocoaModem) and G3YYD
(2-Tone).  The software decoders do a better job when supplied with
audio at least 400 Hz wide without frequency shaping from the IF (DSP)
filter.  The Dual Band Pass filters in general introduce significant
phase delays and amplitude inequality which results in poorer decoding
accuracy in modern FFT based demodulators - although the frequency
shaping may be of value in older amplitude (filter/detector) style
demodulators.


73,

    ... Joe, W4TV


On 1/6/2014 1:26 PM, Mike K8CN wrote:
> Lee,
>
> Ed, W0YK, has a commentary on this very subject in the current issue of NCJ
> (subscription required).  Perhaps he will weigh in directly here, but his
> recommendation was to use the normal filter rather than dual passband. This
> is not an issue unique to the K3.
>
> 73,
> Mike, K8CN
>
>
>
> --
> View this message in context: http://elecraft.365791.n2.nabble.com/Dual-Pass-Band-tp7582564p7582570.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:Elecraft at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>