[Elecraft] [K3] Anyone Interested in A 750 Hz, 8-Pole (INRAD) Roofing Filter?

[Joe Subich, W4TV]

 > I would prefer to see some sort of add-on board that would allow for
 > more filters to be installed so I could have at least one more or
 > perhaps 2 more filters in my K3.

This is a good idea but might not be practical if the KRX3 is
installed or for use in the KRX3.  An alternative would be the
hinted at dual bandwidth (switchable) filters from Elecraft.

 > I would love to toss out the 2.7 as it is too broad for SSB but for
 > an unclear reason, we cannot use the 2.1 to transmit through.

I would prefer a 2.4 KHz replacement for the normal 2.7/2.8 KHz
filters on both transmit and receive which could the be coupled
with the 1.8 or 1.5 KHz "narrow" filters).  It also frustrates me
that we can not use the 13 KHz (FM) filter for AM/ESSB transmit
without resorting to setting the bandwidth to 6 KHz in the filter
configuration.

73,

    ... Joe, W4TV

On 6/19/2010 8:20 AM, Bob Naumann wrote:
> I would prefer to see some sort of add-on board that would allow for
> more filters to be installed so I could have at least one more or
> perhaps 2 more filters in my K3.
>
> The 750 would be too wide for CW and would not replace the 500 in my
> radio.
>
> I own the following;
>
> 200Hz, 500Hz, 1k, 2.1k, 2.7k, 6kHz.
>
> They all work well and have their own purposes. I would love to toss
> out the 2.7 as it is too broad for SSB but for an unclear reason, we
> cannot use the 2.1 to transmit through.
>
> So, one of my 6 filters cannot be used because there are only 5
> slots.
>
> I want all 6. I would love to add a 12kHz for FM if there was space
> for it too as a 7th filter.
>
> W5OV
>
> -----Original Message----- From: elecraft-bounces at mailman.qth.net
> [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Gary Hvizdak
> Sent: Saturday, June 19, 2010 3:39 AM To: elecraft at mailman.qth.net
> Cc: support at unpcbs.com Subject: [Elecraft] [K3] Anyone Interested in
> A 750 Hz, 8-Pole (INRAD) Roofing Filter?
>
> As I see it, some benefits of a 750 Hz width filter are that ...
>
> o   It's about the optimal width if you are only getting one CW
> filter for general (i.e. non-contest) use.
>
> o   For all but the most serious CW contesters, it would make a
> perfect one/two combination along with either the INRAD 400 or 250 Hz
> filter.
>
> o   In most applications it can replace both the 1 kHz and the 500 Hz
> 8-pole filters, thus freeing an existing slot or saving on an initial
> purchase.
>
> Please email webmaster at unpcbs.com to express your interest in
> purchasing a 750 Hz 8-pole INRAD roofing filter for your K3.  If
> there is sufficient demand, then we will special order them in
> batches of ten, and offer them at $125 plus our standard shipping and
> handling charges.  We do not intend to stock these filters, although
> if demand turns out to be "astronomical" then we would certainly
> reconsider.
>
> TNX&  73, Gary  KI4GGX  K3 #2724 webmaster, http://www.unpcbs.com/
>