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Series Five Episode Twenty-Five of the ICQ Amateur / Ham Radio Podcast has been released. The latest news, listener mailbag and Martin interviews Robert Chipperfield (M0VFC) about the Tristan da Cunha DXpedition

• The BBC broadcast morse code for 90th anniversary
• ReconRobotics to use 70cm band
• New Chinese Data Mode CP-16
• White Space Devices Consultation
• New owner for Linear Amp UK
• Call to urgent action on 5 MHz
• Buddies in the Caribbean heading back to St. Lucia
• Radio Hams first to discover disappearance of Sandy Island
• N0D special event station celebrating the End of the World
• ZL9HR - They're on their way!

In mid November I sold my Kenwood TS-590 to finance the purchase of an Elecraft KX3 and become a full time QRP operator.  One of the advantages of the KX3 is SDR I/Q output, which can be used to drive a panadapter.  After some fidling around, I have a configuration that works with the popular NaP3 software and thought I would share the highlights in hope of saving you some effort.  This is by no means an exhaustive setup and configuration guide for NaP3, but it should be enough to get you started.  Remember you can click on the images to enlarge them.

For this example I have used the integrated sound card in my PC and have not yet put a ground loop isolator inline which are both opportunities for improvement.

NaP3 Audio In Advanced Tab

We begin by manipulating the input sound card port configuration as shown above.  This will vary somewhat from sound card to sound card, but we want to be sure that we are capturing two channels and that the sampling rate is set at the maximum your card supports, which may take some experimentation and is not necessarily the highest sampling rate shown in the drop down.

NaP3 Setup Tab

Here on the setup tab of the NaP3 configuration, we need to select the sound card input we are using and where we would like NaP3 to output decoded audio.  Once again we have the option to manipulate the sampling rate, which as you can see is 48k for my sound card.  In addition, we need to select “Elecraft K3” for the Rig Type and specify our CAT parameters.  I began this adventure trying to use the “Elecraft KX3” Rig Type, but I found it to not work very well.

NaP3 IF Tab

Here is the “fun” part, at least it was for me until I started banging my head on the desk.  Be sure to set your “Global Offset” to 0 and select “Swap I/Q Channels”.  The “IF Frequency Offsets” is where you will have to spend some time playing.  The method I used was to tune to WWV in CW mode on the KX3 and determine the differential between the frequency displayed on the KX3 and the panadapter display.  I then set the offset to compensate.  To configure the offset for USB and LSB modes, I reduced the offset by the amount equal to my CW sidetone.  This should get you pretty close, but may still require a little tweaking.  Feel free to try my numbers, but I am unsure if they are valid from KX3 to KX3.

If you determine some other method to set the offsets, please let me know as this is the most time consuming portion of the configuration.

NaP3 Spanadapter View

When it is all over, this is similar to what you will end up with, a nice broad view of the spectrum centered on your rigs current frequency!

Series Five Episode Twenty-Five of the ICQ Podcast has been released. News Stories include :-

• The BBC broadcast morse code for 90th anniversary
• ReconRobotics to use 70cm band
• New Chinese Data Mode CP-16
• White Space Devices Consultation
• New owner for Linear Amp UK
• Call to urgent action on 5 MHz
• Buddies in the Caribbean heading back to St. Lucia
• Radio Hams first to discover disappearance of Sandy Island
• N0D special event station celebrating the End of the World
• ZL9HR - They're on their way!

Listener mailbag and Martin interviews Robert Chipperfield (M0VFC) about the Tristan da Cunha DXpedition

At the urging of my friend Bob W3BBO during our weekly Saturday Echolink BS session, after we were done, I went down the basement shack and removed the Butternut from my K3. In “Antenna 1”, I hooked up the 88′ EDZ and in “Antenna 2” I hooked up the W3EDP.

I then proceeded to go to 160 Meters to go listen to the contest traffic there.

Switching between “Antenna 1” and “Antenna 2”, I was able to make some comparisons between the two.  First off, there was virtually no noticeable difference in the receive quality of any of the signals I heard.  Both antennas gave me loud, strong signals to listen to.  Neither was noticeably weaker or quieter than the other, and switching back and forth was instantaneous. The comparison in reception was easy to make.

On transmit, it was a different story.  The best match I was able to get with the EDZ on 160 Meters was between 2:1 to about 1.6:1.  And to get that match, the K3’s autotuner took it’s good sweet time – I’d say about 5 seconds or longer to achieve that match (seems like much longer while those relays are chattering away!).  The W3EDP?  A quick little “brrp” lasting about a second or two at the most, and a match that was 1.0:1.

In the space of a matter of a few minutes, I made contest QSOs with K8NVL in Ohio, WA1BXY in Rhode Island and NX2X in New York. All of them with the W3EDP.

Is this the solution I am looking for for 160 Meters?  No, I’m not that stupid.  But it will allow me to have some 160 Meter fun this winter until I get something dedicated built. Of course, that project has been on my radio project horizon for two years now.  Next spring/summer I am really going to have to follow through.  But for now, this will do.

72 de Larry W2LJ
QRP – When you care to send the very least!