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Elecraft K3
COM Port Sharing:
written by, Tony McClenny, N3ME
The K3 has a single RS-232 (COM) port. When you wish to use
the computer to K3 COM port connection for general and/or contest
logging software as well as CW, PSK, and RTTY, the single hardware
COM port on the K3 limits your ability to have multiple COM ports
talking to the K3, thus you need a hardware interface or a software
solution.
Initially, I used a
RIGblaster pro© hardware interface and it worked very nicely.
However, as the K3 is designed to provide PSK and RTTY operation
with the simple installation of two cables from the computer sound
card to the K3 rear panel, it seemed like overkill to use such an
interface. Directions for the use of PSK and RTTY operation are
available in this document.
I use the N1MM
Logger© program when contesting and the DX4Win© logging program for
day-to-day contact logging. I discovered a software solution, which
allows me to operate multiple programs at the same time using
“Virtual” COM ports.
N1MM Logger© Logging software
This software is available from: http://www.qsl.net/w2va/freeware.htm
DX4Win© Logging software
This software is available from: http://www.dx4win.com
Another ham suggested I consider the use of “LP-Bridge” © software
written and supported by Larry M. Phipps, N8LP. The software is
provided as “Freeware” on his website located at:
www.telepostinc.com.
According to
information posted on Larry’s website, the LP-Bridge software is
unique as it creates a mirror K3 in the computer’s memory, with
constantly updated data about the current state of the hardware.”
Your first step
should be to set your K3 to 38400 baud. This is accomplished by
pressing and holding the “Menu” button on the front of the K3 until
the “Config” window is displayed. Turn the VFO “B” knob clockwise
until “RS232” is displayed and then turn the VFO “A” knob clockwise
until “38400 b” is displayed. Finally, press the “Menu” button
again to set these parameters.
Using Microsoft’s
Internet Explorer browser software or your personal choice of
browser, go to where you will find Larry provides a simple “click
and download” capability of a “ZIP” type file so it is easy to
obtain the software via the Internet.
Once the software is
downloaded to your computer, extract the files into a temporary
folder and then run the software to install it on your computer.
The LP-Bridge program will display a screen similar to the one shown
below. Note: Default data has been modified in the picture shown
in order to work on my computer.
This screen shot
shows my current setup and I will comment on the various entries
below the picture.
Note on the
LP-Bridge screen display, you must set the “K3 Com Port” to an
actual hardware COM port of your choice. Set the LP-Bridge software
to the computer COM Port that is directly connected by RS-232 cable
to the K3. The “K3 Com Port” must also be set to the same baud rate
as the K3. The default setting on my computer happens to be COM1 but
you may select any hardware COM port available in your computer by
using the down arrow located on the right side of the “K3 Com Port”
box located directly below the picture of the K3. You will notice
38400 is automatically displayed directly below the hardware COM
port box.
Your next step is to
use your mouse and left click on the “Connect” box, which is also
located directly below the picture of the K3. If your radio is set
properly to 38400 baud and you have selected an actual hardware
COM1, COM2, COM3, etc. the “Connect” window will change to
“Disconnect” and data showing the status of your K3 will be
displayed in the far right column of the LP-Bridge window.
It is now time to
setup up one or more “Virtual” Com Ports using the LP-Bridge
software. During my installation, I setup “Virtual Com Port #1” to
be COM 5 from which I operate my logging programs (DX4Win and N1MM)
and “Virtual Com Port #2” to be COM6 from which I operate various
digital modes via computer software such as:
CW Decoder
XP© Send and receive computer assisted CW
This software is available from:
http://www.ac6v.com/morseprograms.htm
MMTTY©
Send and receive computer assisted RTTY
This software is available from:
http://mmhamsoft.amateur-radio.ca/mmtty/
WinPSK©
Send and receive computer assisted PSK
This software is available from:
http://www.qsl.net/w2va/freeware.htm
Instructions for the
setup of each of these programs is available on my website:
www.n3me.net
http://www.n3me.net/howto.htm
Each program must be
installed on your computer and during the setup of each, select the
“Virtual Com Port” port of your choice. “Virtual Com Port” COM5 and
COM6 are simply the virtual COM ports that I elected to use. You
may select any COM port number as long as it is not an actual
hardware COM port you may have installed in your computer.
Remember, you only need one real hardware COM port in order to use
this software. All the “Virtual Com Port” selections are not real
computer hardware COM ports.
You can enter the
name of the program or function you are using with each “Virtual Com
Port” if you wish in the box labeled “Pgm”. In my installation, I
named the “Virtual Com Port #1” “Pgm” box “Logging” and the “Virtual
Com Port #2” “Pgm” box “Digital Modes”.
The LP-Bridge
software will remember your setup of virtual ports, when used the
next time.
There are a few
steps to take, when using the “LP-Bridge” program.
- Boot up your computer
- Turn On your K3 radio
- Run LP-Bridge
- Once all is running, you can use whichever
ports you have setup.
Power “Gain” Calibration:
The following
comment comes from an e-mail dated February 26, 2009 written by
Wayne, N6KR.
There isn't any "100
W calibration" on the K3. All gain calibration is done at 5 and 50 W
(and optionally 1 mW if you have a KXV3). These are the points we
picked do the cal, and the firmware then extrapolates from there.
So, how accurate the rig is at any setting from 13 to 100 W depends
on whether you've done the 50 W calibration.
There is one
additional form of optional calibration: the K3's wattmeter. See
CONFIG:WMTR in the owner's manual.
PSK and RTTY operation:
- Turn the Elecraft K3 transceiver “Off”.
- Connect “Line In” port on rear of
transceiver to computer “Line Out” using a monaural cable.
- Connect “Line Out” port on rear of
transceiver to computer “Line In” using a stereo cable.
- Turn the Elecraft K3 transceiver “On”.
- Press the “MENU” button briefly and “MAIN”
will display on K3
Turn the “VFO B” dial until “MIC SEL” is
displayed
Turn the “VFO A” dial until “LlnE ln” is
displayed
Press the “MENU” button briefly and the
“MENU” will close
- Press and hold “MENU” button until
“CONFIG” is displayed on K3
Turn the “VFO B” dial until the “RS232”
item is displayed
Turn the “VFO A” dial until the baud rate
is 38400 b
- Set transceiver to ½ maximum transmit
power level
Press the “VOX” button to
Set “VOX”
to On
Press the “MODE” button repeatedly to
Set “MODE” to
Data
Press and hold the “DATA MD” button until
“45 bPS” is displayed on K3
Turn “VFO B” dial until “AFSK A” is
displayed
Press and release the “DATA MD” button
The transceiver is now set for “AFSK RTTY”
operation as long as the “MODE”
remains set to “TX DATA”
- Once you have accomplished steps 1 – 8,
you are ready to load the digital software of your choice for CW,
PSK or RTTY operation.
K3 Breakout
Box:
Bud Governale
provided a wiring diagram for a breakout box that he made to capture
all the possible needed connections that come from the K3 accessory
connector. Using this box, one can use two COM ports with RS232
cables; one for radio control and one for FSK RTTY keying. The
diagram is available as a .pdf file from my website:
www.n3me.net/pdf/K3 Breakout Box wiring diagram.
PSK, AFSK and FSK Mode Programming Information:
These comments are
taken from an e-mail written on April 2, 2009 by Joe Subich, W4TV.
“That depends on how
you define "PSK" mode ... Most Yaesu transceivers and the Elecraft
K3 support audio based data modes useful for PSK.
The Elecraft K3 has separate PSK, AFSK and FSK modes.
The K3 needs to be operated in extended CAT mode (K31 On). The CAT
"data" modes are "normal" (MD6;) and Reverse (MD9;)
The data submode is set with the DT; where:
DATA A = DT0
AFSK A = DT1
FSK D = DT2
PSK D = DT3
note: PSK D is only
useful with the KY; command.
For FSK D and AFSK A, "normal" is LSB and "reverse" is USB.
For Data A and PSK D, "normal" is USB and "reverse" is LSB.
The data submode is indicated in the 35th byte of the IF response.”
Headset Information:
If using the Heil
Pro Headset via the Front Panel connection:
Press and release
the “MENU” button
Turn the “VFO B”
knob to:
Set “MIC SEL”
FP.L
Set “VOX GN”
51
Press and hold the
“MENU” button until “Config” is shown on the K3 display.
Set “AF Gain” High
In an e-mail written on August 1, 2009, Don, W3FPR, provided the
following information:
“If that is a standard Heil headset (with
a dynamic mic element like the HC4 or HC5), then you should *not*
have bias turned on. If you have the Proset K2 (with an electret
mic element) or a Proset with an -iC (Icom) suffix, that also has an
electret element and will require bias.
The "H" or "L" refers to the microphone
gain range and *not* to the bias level. You may want to try the low
range to have more control over your mic gain (your mic level
setting will require higher numbers).”
To temporarily increase the headphone
volume, open the K3 Utility program and choose “Command Tester”.
Enter the following code on the top line and hit “Enter”: !66;
You can do this several times and the
volume will increase slightly each time. This is NOT remembered if
you shutdown and restart the K3.
AGC Discussion:
The following is a quote from an e-mail
written by Wayne, N6KR and Lyle, KK7P on February 25, 2009.
Details:
Some operators described a "merging" of
multiple, close-spaced signals when listening to pileups, making
individual signals hard to copy.
Assuming that a narrow crystal filter is
in use (close to the DSP bandwidth), this is not "desense". In most
cases, we've discovered, the cause is IMD (intermodulation
distortion) related to the AGC algorithm.
To simulate what happens under pileup
conditions, we combined four crystal oscillators with gaps between
them of 5, 6, and 7 Hz (a total spread of 18 Hz for the four
signals). We then injected the signals into the K3 at an equal level
of about S5 and used spectral analysis to examine what happens to
the passband. With AGC-F turned on (AGC fast, set to the K3's
factory defaults), IMD products came up some 20-25 dB as compared to
AGC OFF. The situation could be far worse in an actual on-air
situation with more signals, noise, and key clicks. (AGC-S makes
only a small improvement.) We ran the same test on several other
radios, and verified the AGC-induced IMD characteristics are
similar.
IMD is generated because AGC can cause
mixing between the tones and their harmonics. The faster the decay
rate, in general, the more products will be generated. With just one
or two signals, most products will be outside the DSP's narrow IF or
AF passband. But in a pileup, where signals are greater in number
and can be nearly on top of each other, there are many more
opportunities for signals to combine. This results in IMD products
spaced at 1 to 20 Hz, depending on the time constants, location of
the signals, etc.
Turning AGC off is one strategy that
operators have traditionally used to combat the effects of AGC
modulation. It then becomes necessary to "ride" the gain controls.
Neither Lyle nor I have that much patience :)
So we took a different approach: keep the
AGC on, but reduce its modulation effects to negligible levels by
adding a very long "hold" time.
In the field-test firmware, two changes
have been made. First, the AGC HLD menu setting, which used to apply
only to voice modes, now applies to CW as well. (It still only
affects AGC-S, the slow AGC setting.) Second, we increased the range
of AGC HLD to facilitate experimentation. What we found is that an
AGC hold time of about 1 second, combined with a slower AGC-S decay
time, reduces in-band IMD with closely spaced signals by 20-25 dB,
making it very similar to turning AGC off. The *attack* time is
unaffected, so there is no "thumping" as you might have with
audio-derived AGC. Any new signal peak above the one that starts the
"hold" timer will restart the timer.
This "hold" AGC appears to be useful in
many listening situations. It can make voice signals sound cleaner,
as well; after all, a voice signal can have many components, and AGC-induced
modulation can add IMD products. It also helps with noisy band
conditions.
The down side to AGC "hold" is that large
signals can charge it up to a high level, reducing gain for the
duration of the hold time. But in many cases this is far preferable
to the AGC IMD effects, especially if you're listening to many
signals at similar amplitudes -- as in a pileup.
AGC Settings:
To modify the
factory default AGC settings, press and hold the “Menu” button until
“Config” is shown on the K3 display. Turn the “VFO B” knob until
“AGC DCY” is displayed. Then turn the “VFO A” knob to the setting
you prefer.
Dave, K6LL, and
Ignacy, NO9E made the following suggestions for AGC settings for
general use in e-mail messages.
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Dave, K6LL |
Ignacy, NO9E |
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DCY |
Soft |
Nor |
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|
HLD |
0.20 |
0.50 |
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PLS |
nor |
Nor |
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SLP |
0 |
010 |
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THR |
8 |
005 |
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F |
200 |
150 |
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S |
020 |
020 |
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Carrying Case:
It has been
suggested that a Pelican 1520 would be appropriate perhaps with the
optional 1527 nylon travel bag. TSA-compliant locks should be used.
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Spurious Signal Removal:
In an e-mail written on May 26, 2009,
Wayne, N6KR, addressed this with the following.
“The K3 is a very high-dynamic range,
down-conversion superhet. It's nearly impossible to remove all
birdies in such a design. But we think we did a pretty good job of
it :)
If you have any left (that you can hear
with an antenna connected), you can "remove" them using the SIG RMV
menu entry in the CONFIG menu.
Below are the instructions for SIG RMV,
from the latest owner's manual (not released yet).”
SPURIOUS SIGNAL REMOVAL: Fast-tuning
“birdies” can in some cases be eliminated using the SIG RMV menu
entry. We recommend that this be attempted only on birdies that can
be heard with an antenna connected.
(In SSB modes, simply leaving auto-notch
on may be effective.)
STEPS:
(1) Set up the receiver for a desired
band, and select the mode you’d normally use in the target band
segment. Also set the DSP passband controls to the settings you use
most often (e.g., NORMalized by holding NORM).
(2) Locate a birdie to be removed. A
birdie is considered “fast-tuning” if a small change in the SHIFT
control (e.g. 50 Hz) moves the birdie about 400 Hz or more (with a
narrow filter selected, this small shift may move it completely out
of the passband). Such birdies result from UHF harmonics of the VFO.
If you test a birdie using SHIFT, be sure to return SHIFT to its
normal setting before continuing, because the value of SHIFT affects
the birdie frequency.
(3) Change the SIG RMV parameter to 0.
This will save necessary information about the birdie, including the
present VFO frequency, mode, filter, and SHIFT value.
(4) Try different parameter values,
starting with -1 or 1, to see if the birdie can be removed (shifted
out of the audible passband). Use the smallest effective value.
Important: If you change the parameter,
exit the menu and see if the birdie has disappeared. Each SIG RMV
value applies to a single 100-Hz VFO segment, e.g. from 28135.30to
28135.39, so you’ll have to tune slowly through that 100-Hz range
using 10-Hz steps to make sure the birdie has been completely
removed. You may hear a slight tuning artifact as you tune in and
out of the mapped-out segment.
Note: In many cases, you’ll need to apply
SIG RMV to at least two adjacent 100-Hz VFO segments. Also, if you
use more than one filter bandwidth or SHIFT setting in the present
operating mode, you’ll probably need to map out the birdie more than
one time. If you change your CW sidetone pitch, you may need to
re-do the procedure.
To undo SIG RMV:
If you tapCLR while you’re in the SIG RMV
menu entry, all birdie information for the present band will be
permanently deleted.
Limitations:
SIG RMV applies only to CW/SSB/DATA
modes, and only to the main receiver (at present). Do not remove
birdies on transverter bands; instead, remove them on the I.F. band.
On each band from 160-6 m, up to 60 birdies can be removed. But as
mentioned above, each one may have to be mapped out from adjacent
VFO segments as well as for different filter and SHIFT settings. So
the number of birdies that can be completely removed is around 5 to
20 per band.”
Ten-Tec Titan Amplifier Connection:
Connect a line with
an RCA connector to the K3 “Key Out” and an RCA connector to the
Titan “Push To Talk/Vox”.
This provides RF
generation before keying the amp relay and keeps the relay closed
until RF ceases.
K3 Crystal Filter Setup:
The following text
is copied from an e-mail written by Wayne, N6KR on February 13,
2009.
Taken from Offset (FLx FRQ)
----------------
There are many considerations that go
into the positioning of the K3's crystal filters with respect to the
I.F. center frequency. We shift them upward if the filter is too
wide to be centered at Fc/2 + 200 Hz, thus preserving the lower edge
of the filter around 200 Hz. This usually happens only in CW mode,
typically with lower sidetone pitches.
The result is optimization for
opposite-sideband rejection. You can argue for a different approach,
but the K3's success in CW DXing and contesting suggests that this
approach is just as valid as any other.
I don't recommend trying to fool the
firmware by adjusting the crystal filter offsets; I'd use the marked
values. Changing them is likely to cause unwanted side-effects,
since the filter passband is inverted for complimentary modes (CW/CW
REV, LSB/USB, DATA/DATA-REV). The exception to this rule is when
fine-tuning the offsets of 5-pole filters on the main and
sub-receivers in order to provide best performance in diversity
mode. These adjustments will rarely be larger than +/- 20 Hz anyway.
Bandwidth (FLx BW)
------------------
It's OK (but not necessary) to fudge the
bandwidth of specific filters (FLx BW). For example, INRAD's 8-pole
"400 Hz" filter can be declared as 0.4, 0.45, or 0.5 kHz, depending
on where you want this filter to be kicked in as WIDTH is rotated.
The audible effect is subtle. Ed Muns, W0YK, has described this
technique in detail elsewhere.
Gain (FLx GN)
-------------
Regarding filter loss compensation: I
recommend simply sticking with what's on page 46 of the owner's
manual (1 to 2 dB compensation for 400-500 Hz filters, 3 to 4 dB
compensation for 200-250 Hz filters, and 0 for all others) unless
you have a very specialized application and lots of time on your
hands.
There are three reasons for this.
(1) The *perceived* loss of a crystal
filter is a function of both actual loss and S/N ratio. If a
narrower filter has a little more loss, you may not notice it.
(2) Most signals are flattened slightly
by AGC anyway.
(3) Adding a lot of gain to filters can
again cause side-effects, such as interaction with RX EQ settings
and variations in gain between main and sub if the filter
complements are different (e.g., during diversity use).
In fact we recently issued new guidelines
for factory-assembled K3s: all crystal filters' FLx GN numbers
will be to 0 except for 400-500 Hz (1 dB) and 200-250 Hz (2 dB).
Customers are free to optimize these
further, of course -- but most won't need to.
73,
Wayne, N6KR
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