On 2025-12-06 2:34 PM, Rick NK7I via Elecraft wrote:
2.7 can be used in all modes but FM (not wide enough).
2.7 can not be used in AM (not wide enough)
AM requires either the 6 or 13 KHz. FM requires the 13 KHz.
Factory default is to use 2.7 or 2.8 KHz for SSB, data and CW
transmit. Bandwidth is defined by the DSP modulator - the only
need for the IF filters in transmit is to remove the mixer image
at 8245 KHz.
73,
... Joe, W4TV
On 2025-12-06 2:34 PM, Rick NK7I via Elecraft wrote:
2.7 can be used in all modes but FM (not wide enough). As you narrow the
bandwidth control, the filters will switch (if in place and enabled). (Also
from memory, now using K4s).
To answer the OP, I suppose someone might want to hear a 2.7 KHz wide CW
spectrum but that’s a lot of abuse to the ears; 500 (even in a contest) would
make more sense. If other narrower filters were installed, I wouldn’t use 2.7
on CW.
(250, is really about 325, it’s not that sharp. Most found it not worth the
expense.)
73,
Rick nk7i
On Dec 6, 2025, at 11:21 AM, Rich Newbould via Elecraft
<[email protected]> wrote:
If memory serves my correctly the 2.7 filter is used for TX on all modes,
except AM
I could be wrong
Rich
On 12/6/2025 1:35 PM, Tony Casciato via Elecraft wrote:
Was poking around in the K3 Utility this morning and noticed in the
Configuration tab/Crystal Filter Configuration panel there are Radio Button
choices for a TX CW filter to use Filters 1 thru 5; mine defaults to Filter
3 which is the 2.7Khz 5-pole standard one. I also have Filter 4 (500Hz
5-pole) and Filter 5 (250Hz 8-pole) available. Should it be set to
something different for CW?
I looked in the "Help" text, asked Google and didn't see an option to
search these Mailman messages. I figured it was ok to ask here once and
it's mostly a curiosity.
Thanks and 73,
Tony, KX3H
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[email protected]
This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to [email protected]
