Re: KPA1500 and FT8

Posted by David Woolley (E.L) on Mar 05, 2018; 10:03am
URL: http://elecraft.85.s1.nabble.com/KPA1500-and-FT8-tp7638861p7638897.html

I believe at least some of the DSP filters in the K3 are FIR (Finite
Impulse Response) ones, which should be phase linear.  The roofing
filters will not be phase linear, so I would think you could get away
with using a narrow DSP filter, as long as you used a relatively wide
roofing filter.

This will still leave the ADC, and the analogue circuitry between the
roofing filter and it, open to overloads, but will protect the sound card.

On 04/03/18 21:15, Jim Brown wrote:
> There is a VERY good reason why WSJT developer, K1JT, advises users to
> use wide IF bandwidth, and it's NOT the panoramic display. The reason is
> that filters introduce phase shift in the passband, and phase shift is
> the enemy of good decoding. The same physics, by

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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