[Elecraft] Width of AM filter

[Wes Stewart]

I was going to suggest an LC filter for non-critical work.  If Elecraft would supply "replacement" carrier boards with the pin sockets either mounted or available it would be nice.

--- On Thu, 3/26/09, VE3NFK <john.turgoose at gmail.com> wrote:

> From: VE3NFK <john.turgoose at gmail.com>
> Subject: Re: [Elecraft] Width of AM filter
> To: elecraft at mailman.qth.net
> Date: Thursday, March 26, 2009, 7:42 PM
> I hope I am not stepping on any toes - but I found someone
> who had designed a 13Khz +/- filter with some toroids and
> caps - incl variables to adjust and built two and they work
> great in main KRX3 -
> just confirmed again they give nice fidelity on AM  - and I
> can hear the 6khz filter click in when I reduce BW to 3... 
> low cost - fair bit of labour :-)
> 
> 73 John VE3NFK
> 
> 
> Jerry,
> 
> The WIDTH control sets the final audio bandwidth, which is
> limited to 5 
> kHz in AM mode. But in AM mode, the crystal filter
> bandwidth needed is 
> 2x the audio bandwidth, or 10 kHz in this case, because it
> has to pass 
> both sidebands. To obtain this full bandwidth, you'd
> have to have the 
> 13 kHz FM filter installed. The AM filter is only 6 kHz
> wide (an 
> industry standard), and if that's the widest filter you
> have, you're 
> actually getting only a little over 3 kHz of audio
> bandwidth even if 
> you set the WIDTH control to max (5 kHz).
> 
> 73,
> Wayne
> N6KR
> 
> On Mar 26, 2009, at 11:23 AM, Gerard Jendraszkiewicz wrote:
> 
> > Hello,
> >
> > I have K3 with KFLA-6K. I can only adjust the width to
> 5.0 using the
> > width knob on the K3. I use AM to listen to the AM BCB
> and some SW. I
> > remember getting a wider width in the past ?? Any
> suggestions ?
> >
> > Thanks
> > Jerry, KE9I
> >
> >
> ______________________________________________________________
> > 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
> >
> >
> 
> ---
> 
> http://www.elecraft.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
> 
> 
> 
> -- 
> View this message in context:
> http://n2.nabble.com/Width-of-AM-filter-tp2540204p2542146.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