[TenTec] PBT and other issues.

[Rick - DJ0IP / NJ0IP]

Yes, and we can also add in insertion loss as another factor.

As for the Elecraft K2 filter, well we don't want to criticize it too much;
after all, they did copy Ten-Tec's patented Jones Filter for that radio.
;-)

73 - Rick, DJ0IP
(Nr. Frankfurt am Main)


-----Original Message-----
From: TenTec [mailto:tentec-bounces at contesting.com] On Behalf Of Jim Brown
Sent: Wednesday, October 29, 2014 5:03 PM
To: tentec at contesting.com
Subject: Re: [TenTec] PBT and other issues.

On 10/29/2014 8:24 AM, Rick - DJ0IP / NJ0IP wrote:
> Although we speak of filters as being 2.4 kHz or 500 Hz bandwidth, that is
only a small part of the story.
> The bandwidth we state here is the "6dB bandwidth".  Perhaps more
important is the "60dB bandwidth".

Also important is the amplitude and phase response WITHIN the passband. 
Poor design can produce poor phase response, which degrades speech
intelligibility. This was a major shortcoming of the Elecraft K2 -- it
sounded fine listening through the full bandwidth TX filter, but when the
multipole CW filter was realigned for narrow SSB it was hard to listen to.

73, Jim K9YC

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