Wonderful ! A better answer I could not imagine. Thanks Don. Most excellent information.
73, Mike VE9AA Mike, Coreen & Corey Keswick Ridge, NB -----Original Message----- From: Don Wilhelm [mailto:donw...@embarqmail.com] Sent: January 8, 2017 12:45 PM To: Mike Smith VE9AA; Elecraft@mailman.qth.net Subject: Re: [Elecraft] K2 Filter question Mike, The K2 has a built-in 5 pole filter on the RF board that you can set to variable widths using the CAL FIL menu - you must have the internal counter probe to change the filter settings. There are 4 filter settings for each mode. These are not "roofing filters" as used in the K3, but IF crystal filters. The filter type in the base K2 is of a Cohn design and the width can be changed as I stated above. Its design width is about 500Hz and gives a nice passband from about 1.5kHz down to about 200Hz. It can be widened out to SSB listening levels, but the passband becomes quite ragged at those wider widths. It is however suitable for SSB listening. The filter on the KSB2 option board has a nice flat passband. The KSB2 option (for SSB) has a fixed width 7 pole filter. The early filters were 2.1kHz width, but more recent filters are 2.4kHz. Elecraft has a capacitor kit which will allow you to change the filter width. The crystals used in the K2 filter were upgraded to better speced crystals at SN 2560. I would recommend that K2s below that SN be upgraded with the new crystals. Elecraft sells a kit of matched crystals at a very reasonable price a set of 7 for the base K2 or a set of 14 for both the base K2 and the KSB2 option. 73, Don W3FPR On 1/8/2017 11:10 AM, Mike Smith VE9AA wrote: > It's Mike, VE9AA...I own a K3 but almost never use it (only for FD and > portable ops -I've used it twice in my year of ownership) > > I am thinking about maybe buying a used K2/10 with many options,(no DSP > board I don't think) but as I don't know a thing about the K2 (and after > reviewing the Elecraft website) I had this hopefully simple question. (I > have not yet contacted the seller) > > > > Are there optional CW filters still available for the K2 or does it come > with them all built in ? > > > > I do mostly CW so was looking at doing most of my operating with a 200-300Hz > filter.(and perhaps with a 1.8kHz SSB filter when I am on phone) > > > > I apologize if the answer is overly obvious ! > > > > Thanks much, > > > > dit dit Mike VE9AA > > > > Mike, Coreen & Corey > > Keswick Ridge, NB > > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to donw...@embarqmail.com > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
