There you hit the word I was looking for, "rumble". I have the narrow
250 Hz filter in a 706 and a 718. That sums up the difference between
them in the K2. With those filters there is more rumble, and sometimes
the signals blow right by the filters and blast you if you have the
volume up. With the filters in the K2, I find that I can use the wider
bandwidths more than expected, and that the effects of the filter on the
received audio is "softer". If that makes any sense, where the received
audio with the other units with narrow filters is harsher.
David Wilburn
[EMAIL PROTECTED]
K4DGW
K2 #5982
Brett gazdzinski wrote:
I did some comparisons between my 756 pro and the K2
on 40 meters tonight, only CW, SSB always hurts my ears
so I cant say about that, plus I don't have the ssb option
added to the K2.
I used headphones, the same antenna, and tuned in strong
and weak signals, some had very close qso's going on, and
others had ssb splatter, and lots of atmospheric noise,
static crashes, etc. I have a station control setup that allows
me to select any antenna, receiver, transmitter, etc, so
doing A/B comparisons is easy.
I got to say, I never really spent a lot of time comparing the
two radios before, but the 756 pro sounds HORRIBLE!
There was a lot of weird things coming out of the 756, much more
noise and rumble, I suspect the early stages are being
subjected to all sorts of interference, and while its filtered
out, the results still come through somehow.
Static crashes came through as massive rolling waves of rumble
and other noise. CW sometimes sounded fuzzy and weak on the
756 yet its clear on the K2.
I cant even hear the static crashes on the K2, the close in ssb
splatter I can barely hear on the K2, and I don't hear close cw if I
narrow the filter on the K2.
I dislike narrow filters, but the 200hz filter setting I have
on the K2 sounds much better than the 400 hz 756 pro filter setting.
If I had to listen to the 756 on CW or ssb for long under conditions
like what was on 40 tonight, I think I would rather turn it off.
I played around setting the filters up a bit when I got the K2 done,
but did not really get critical, I just tried a few different settings,
BFO pitches, filter widths, etc.
I did manage to get the tone to stay the same when switching between
filters, and using the spectrogram software put the bfo pitch in the
center of the filter bandwidth.
I find it kind of amazing that the expensive in its day 756 pro
sounds so poor.
I used to do a lot of CW on a heathkit HW7, then an HW101, listened
to CW on lots of vintage gear, and the emtech kit, and while some of it
had a lot of built in background noise, or poor filters, I don't
think it sounded as bad as the 756 pro.
Not that the copy is bad on the 756, it just seems to sound very poor.
Maybe that's something that dsp does? combined with all those
conversions?
I would venture to guess, on CW anyway, that if you find ANY rig that
sounds better than the K2 on receive, you have something wrong with your K2.
Brett
N2DTS
I'm a new used K2 owner. I have been getting use to the rig
the last week.
In another thread this was said:
<quote>
I have used Spectrogram to align the filters, and I'll be
doing that again with a
bit more experience. That made a significant difference in
the "feel/sound" of
the radio. Like you, I intend to do some more "measurement"
in addition to just
setting things up and starting to operate.
Compared to the FT990, a rig that I have really enjoyed for
many reasons, the K2
is much quieter and more flexible.
</quote>
I have noticed I'm having the opposite experience. I have a
noise floor of S9 on
40m. With my TS-430S and the ssb filter I can listen to the
rig all day. But
with the K2 after a half hour or so I have to turn the sound
down to give my
ears a break. There seems to be so many highs in the
background noise that it
really gets on my nerves in a short time. This is even with
the MFJ DSP filter
inline after the K2.
I don't have the dead tree manuals yet, maybe later this
week. So I haven't
wanted to really get into checking all the adjustments until then.
The rig is dead on frequency, when replying to a cw station.
On ssb I am told my
transmitted signal has great audio, MC42 hand mike. Power out
is good. So, I'm
jumping to the conclusion that it's all set up well. What
gives with all the
annoying highs even when using the cw narrow filters? Only
relief I get is when
I turn the AF1 on.
I did use the spectrogram to move the cw center frequency
from 500hz to 600hz.
When I did this, I happened to set it up on the wrong side of
the passband. A
couple of folks got me straightened out on that. But the
thing I remember was
how wonderfully quiet the rig was when I was on the wrong
side. Signals just
popped up from the quiet and it was a pleasure to hear.
Any suggestions why I'm hearing so many highs? And how I
might could shift
things around to change it when I get the manuals.
TIA
--
GB & 73's
KA5OAI
Sam Morgan
_______________________________________________
Elecraft mailing list
Post to: [email protected]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
_______________________________________________
Elecraft mailing list
Post to: [email protected]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
_______________________________________________
Elecraft mailing list
Post to: [email protected]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com
