[Elecraft] K3 FIRMWARE, Rev. 3.25: Improved NR, 10-Hz SHIFT steps, Received CW WPM display, VFO noise reduction, etc.

[Hector Padron]

Installed already this morning the new Beta FW 3.25 in my K3 # 2192 and the difference is day and night,not only the NR works great now but also the low freq end on Rx audio extended down to 40Hz on SSB and AM as well.When NR is enabled now  the audio remains with the same quality,only reduce the level a little bid but the noise is gone more than 50 percent at least,and the best of all is that I don't hear anymore the hollow sound that all NR has in other radios,it sounds natural,great job Wayne,day by day we all like this radio more and more,73 to all

AD4C



"The difference between genius and stupidity is that genius has its limits".. -- Albert Einstein

--- On Wed, 8/12/09, wayne burdick <n6kr at elecraft.com> wrote:

From: wayne burdick <n6kr at elecraft.com>
Subject: [Elecraft] K3 FIRMWARE, Rev. 3.25:  Improved NR, 10-Hz SHIFT steps, Received CW WPM display, VFO noise reduction, etc.
To: "Elecraft Reflector" <elecraft at mailman.qth.net>
Cc: elecraft_k3 at yahoogroups.com, elecraft at yahoogroups.com
Date: Wednesday, August 12, 2009, 7:49 PM

K3 beta-test firmware revision 3.25 (with DSP rev. 2.21) is now  
available. There are several new features and significant improvements  
in this revision; see release notes below.

Please send problem reports to k3support at elecraft.com. Beta firmware  
load instructions can be found at

         http://www.elecraft.com/K3/k3_software.htm

73,
Wayne
N6KR

* * *

MCU 3.25 / DSP 2.21, 8-11-2009

New Features:

* NOISE REDUCTION (NR) IMPROVEMENTS: Our new NR
algorithm has less impact on signal strength, and should no
longer make some weak signals “disappear” due to over-processing.
We may fine-tune the algorithm in future releases, based on
operator evaluation, but we’ve have good reports from early testers..

* VFO TUNING NOISE REDUCTION: Some operators have reported
hearing noise on 60, 10, or 6 meters when tuning the VFO under
very quiet conditions. If you experience this, try the following:
In the CONFIG:VCO MD menu entry, tap ‘1’ until you see “SPI 2”
(the default is “SPI 1”). This alters the timing of data sent to the
synthesizer, which in turn changes the spectrum of SPI-bus
signal noise. It has no impact on performance. You will also need to
add two resistors and two diodes to the bottom of the RF board
(see application note on our K3 modifications web page).

* AUTOMATIC RECEIVER FRONT END PROTECTION:  If the K3 is
operated too close to high-power transmitters, it’s possible to damage
some receiver components. While this rarely happens, we’ve taken
steps to prevent it by sensing a high-current condition at the mixer
post-amplifier (Q8/Q9) and automatically turning off the preamp and,
if necessary, turning on the attenuator. You will need to add one
jumper wire on the bottom of the RF board (see application note
on our K3 modifications web page). If you don’t add the jumper,
operation will be unchanged; firmware can sense whether or not
you’ve installed the jumper.

* 10-HZ PASSBAND SHIFT STEPS (EXPERIMENTAL):
If CONFIG:PB CTRL is set to SHIFT=.01 for a given operating mode,
the SHIFT control will provide .01 kHz (10 Hz) steps rather than the
original .05 kHz (50 Hz). Especially useful with narrow filter  
bandwidths.
This feature is experimental and has some limitations at present:
Applies to CW and DATA only; LOCUT/HICUT cannot be used when
10-Hz SHIFT steps are in effect; WIDTH steps remain 50 Hz in all cases.
Not compatible with spur removal function yet (CONFIG: SIG RMV);
signals mapped out may reappear.

* CW SPEED DISPLAYED WITH DECODED CW TEXT: If the TEXT
DEC switch parameter is set to WPM CHK (using VFO B), the speed of
on-air CW signals will be shown, along with a small window of CW text.
You might see “18w.  CQ…”, where “18w.” means 18 WPM. Both text
decode and WPM display accuracy can be improved by using narrow
filtering and by careful adjustment of the “THR” (threshold) parameter
(set with VFO A when the TEXT DEC switch is pressed).

* RF GAIN CALIBRATION: The K3’s hardware AGC circuitry can now be
calibrated. This may improve both S-meter and RF GAIN control accuracy.
To do RF GAIN calibration, use revision 1.2.7.24 or later of K3  
Utility (use the
RF GAIN calibration function, under Configuration). This procedure  
calibrates
both main and sub receivers. A signal source is required. Future  
firmware
revisions will further improve accuracy, using the calibration data  
stored
by this procedure.

Misc. Improvements:

* "SK" IS NO LONGER DISPLAYED IN RESPONSE TO NOISE
DURING CW DECODE. Incorrect characters are now displayed as ‘*’.

* 6 METER SCANNING NO LONGER PROHIBITED. Scanning is limited
to the 6-m U.S. ham band (50-54). Exception: In some countries the K3  
won’t
operate on 6 m at all.

* TTY CENTER FREQ NOW DISPLAYED CORRECTLY: In FSK-D
and AFSK-A modes, rotating SHIFT now shows the exact center
pitch (when indicated by an asterisk). The four available center
pitches are 1000, 1360, 1530, and 2210 Hz. Previously the pitch was
rounded down to the nearest 50 Hz.

For Software Developers:

* "RO" COMMAND (RIT/XIT OFFSET READ/SET) ADDED. This
command provides a more direct way to set up the RIT/XIT offset,
as an alternative to “RU” and “RD”. Set/Response format:
ROsxxxx; where s is +/-, and xxxx is 0000-9999.


---

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