Category Archives: DX

Articles and information about DX or distant stations outside the North American continent. Topics include working DX, DXpeditions, DX Stations, DX related antennas, software, and equipment and more.

Little Pistol DXing

For many years, I enjoyed chasing DX from my NH station with two towers, multiple beams, an 80-meter 2-element quad and a 160-meter Inverted L.  I got spoiled with the AL-1200 hammer I used almost constantly whenever a DXpedition came on the air to bag it quickly.  The setup allowed me to bust a contest pileup in just two or three calls.  Ah, the good ol’ days.

I’ve been in FL now for 18 months in a covenant-restricted retirement community.  I was fortunate to find a place with a fair amount of open property that allowed me to put up a couple of low inverted Vees and a multi-band vertical.  The wire antennas drape off a pole on the back of the house, out of sight of most of my neighbors.  The vertical is enclosed in a PVC flagpole with just the 80-meter “stinger” poking out the top.  It may be an ugly flagpole but it falls within the covenant permissible guidelines and, more importantly, keeps the village aesthetic vigilantes off my back. I have about 32 radials fed from the base of the vertical in a ¾ pie-shaped field with lengths varying from 55 feet to 10 feet.  While this is far from the standard practice of at least 100 radials of 65 feet or more (assuming 80-meter capability), it is better than nothing.

As one might expect, DXing has been a far cry from what I was used to.  Hearing stations is a chore, even with a K3 over my old FT-1000MP.  I often find myself irritated at the juicy spot reports from New England that I cannot hear.  Part of the problem is geography; I am at a lower latitude and I line near Ohio longitudinally so gray-line effects are different.  One might think the high threat of thunderstorms down here also generates a lot of noise but it has been dry and quiet during the fall and winter months when DX is most active.

So what is an old DXer supposed to do?  Answer: Back to the future.  When I got my Novice license back in high school, I put up an end-fed long-wire antenna for 80 meters and a dipole for 40 meters, both of them much lower than 1/4-wavelength above ground.  The long-wire was fed with 300-ohm line.  Why?  Because that is what my Elmer and high school buddy told me to do.  I was clueless about matching, common-mode currents and RF in the shack.  I had a Hallicrafters S-38 reconditioned tube receiver that had a barn door-wide filter for CW.  You can understand why it was a thrill to work states west of the Mississippi.  If nothing else, I learned to appreciate a QSO and to be patient when trying to work someone.

My present station has the advantage of all the technological improvements in signal processing and automation that have mushroomed since the tube days.  Stations are still weak when I do hear them but I can work them if they aren’t too busy.  Contesting is actually better since many stations crank up the amplifier and plead for stations late in the contest.  Using an amplifier here is problematic.  My vertical is about eight feet from the shack so RF saturation would be likely.  Furthermore, I would need to run a 220 VAC line to the shack to avoid brownout when using 110 VAC with an amplifier.  The worse thing, however, would be EMP effects on the neighborhood breaker systems.  It seems building contractors have switched to breakers with a much lower RF tolerance than before.

So what a desperate DXer supposed to do?  The easiest thing I can do is put down more radials.  As I mentioned, my radial field is far from ideal, even if I had moist, loamy soil instead of sand.  An ideal radial field would be a copper sheet surrounding the vertical.  In the climate here, it would turn green in a few weeks so it would look like a California painted lawn if it isn’t stolen first.  I decided to double the radial field I have to provide more return paths for the RF currents.  I have not modeled my antenna to see what kind of radiation pattern I have but it is a good bet that the so-called takeoff angle for bouncing off the ionosphere is 40 degrees or higher.  Conventional theory says that a takeoff angle should be 15 to 20 degrees, values usually achievable with yagis mounted 1/4-wavelengths or higher.  The hope is that I can pull-down my takeoff angle enough to where I fall into the usual DX footprints.

When I installed my original set of radials, it was a time-consuming effort to work each wire down through the thick St. Augustine grass here.  I finally got smart one day when trimming the walkways with my weed-whacker set up vertically.  I found that I can lay out the wire and walk along it with the weed-whacker cutting a narrow slice through the grass.  I then drop the wire down into the cut, add a few staples and close the grass around the cut.  The cut will be completely grown over in about a month.  (This technique will work in New England if you have a manicured lawn; the rocks in a natural lawn tend to mess things up.)  To date, I have added eight radials so it is still a work in progress.

For those of you with a modest station, take heart.  With today’s transceivers, propagation predictions, and worldwide spotting it is possible to achieve DXCC on several bands in less than a year.  I have been fortunate to work them all when I was a “big gun”.  As a “little pistol”, I’ve managed to work 176 countries with 144 confirmed.

The chase continues…

Ed (K2TE)

The DX Alarm Clock – Part 1: Raspberry Pi Software

I have been an Amateur Radio Operator for 5 years and my favorite thing to do is chase DX. As a new Ham, it was always a thrill to work a new DXCC, but now that I have over 280 DXCCs and over 1000 band points, it is a little more difficult to find a new one. Add to that the fact that I am trying to get a DXCC in 80m and 160m., which are usually open when I am asleep. I created the DX Alarm Clock as a way to get notified that there is something new on the air when I am not down in the shack.  This article will talk about how I developed the software for the DX Alarm Clock.  Part 2 will talk about building the Raspberry Pi-based Hardware and loading the OS.

DX Alarm Clock Architecture

The DX Alarm Clock is a Python software program running on a Raspberry Pi that gathers data online about my log and what is on the spotting network and uses that data to alert me when there is a “new one” on the air.

Ham Radio Raspberry Pi Project - DX Alarm Clock Architecture
DX Alarm Clock Architecture

The ClubLog website provides a light DX Cluster website called DXLite, which has an XML Interface. The DX Alarm Clock uses this interface to get the current spots. The software uses the Developer API from ClubLog to get a JSON matrix of all DXCC entities by band indicating whether I have worked, confirmed, or verified each band entity. The software loops through all of the spots returned by DXLite and looks each DXCC up in the JSON ClubLog matrix. I also use the QRZ.com XML Interface to get additional information for each callsign that is spotted, like the state.

User Interface

Ham Radio Raspberry Pi Project - DXCC Configuration Screen
DXCC Configuration Screen

The DX Alarm Clock uses Tkinter/TTK for the GUI.  I used the Notebook widget to create a multi-tab GUI.  There is a tab for configuring filters for DX Entity. The user can choose all New DXCCs, as well as specific bands and nodes to provide alerts for.

Ham Radio Raspberry Pi Project - WAS Configuration Screen
WAS Configuration Screen

There is another tab for configuring filters for WAS. ClubLog has no log look-up capability based on US State so the WAS filter lets you create a list of States and associated bands to provide alerts for.

Ham Radio Raspberry Pi Project - Notification Configuration Screen
Notification Configuration Screen

The Notification tab allows the configuration of what notifications the user would like to receive. The user can specify a separate email address for New DXCCs, New Band Points, and New US States. This allows alerts to be sent to email accounts or as SMS texts. You can also configure the sounds the DX Alarm Clock itself makes to “wake you up” when that ATNO or new Band Point is spotted.

DX Alarm Clock Alerting

The DXAlarm clock wakes up every 5 minutes and gets the latest spots from the DXLite Cluster. It checks each spot against the ClubLog log and if there is a match based on the configure filters, it sounds the alert, and then speaks the alarm, giving you the Callsign, DXCC Entity, Band, and Mode.   A simple text-to-speech package called flite (festival-lite) was used to implement the speech on the Raspberry Pi.

Ham Radio Raspberry Pi Project - Alert Screen
Alert Screen

It also puts a message with these details and the Frequency, UTC Date/Time, Spotter and Comment on the display.

Ham Radio Raspberry Pi Project - Text Notification to iPhone
Text Notification to iPhone

Additionally, it sends this information as an email to the configured email address, which results in a text or email.

 

Ham Radio Raspberry Pi Project - Apple Watch Alert
Apple Watch Alert

I can even get the alert on my Apple Watch.

Ham Radio Raspberry Pi Project - Filtered Spots Display
Filtered Spots Display

Once all spots are processed, it keeps a running list of all spots that resulted in alerts on the main screen. Spots are aged out if they do not recur over time.

Ham Radio Raspberry Pi Project - DX Alarm Clock Hardware
DX Alarm Clock Hardware

The DX Alarm Clock just alerted me that ZC4SB is on 20m – that’s an ATNO!  Got to go down to the shack and work him!    Stay tuned for Part 2 of this post on the DXAlarm Clock Raspberry Pi-based hardware and on setting up the Raspberry Pi OS.

Anita, AB1QB

N1FD Enters The CQ Worldwide DX Contest In A Quest To Earn DXCC!

The CQ Worldwide DX SSB Contest has just completed and we made a big step toward our goal of earning an ARRL DXCC Award for our club call, N1FD.

DXCC - N1FD Operator QSOs and Bands
N1FD Operator QSOs and Bands

The following club members operated as N1FD in the contest:

The N1FD Team operated from our station (AB1QB/AB1OC).

DXCC - Joe KB1RLC in CQ Worldwide DX at AB1OC
Joe KB1RLC Operating  in CQ Worldwide DX at AB1OC

Many of the club members who joined us had not previously had the opportunity to operate in a major DX contest. Our approach to the contest included a significant amount of time spent to help folks learn how to operate in a major DX contest such as CQ WW DX. All of the members of the N1FD Operator Team did a great job and we worked a lot of DX given the relatively poor band conditions throughout the contest period.

Hard at work on our DXCC - Our N1FD Multi-op Teams In Action (KC1ENX, KC1FFX, and KC1HHX)
One Of Our N1FD Multi-op Teams In Action (THe Funchum Team – KC1ENX, KC1FFX, and KC1HHX)

We entered the contest as N1FD in the Multi-Op, One Transmitter category and we operated in the High Power, Assisted class. This category allowed us to have two transmitters on the air on different bands simultaneously. One transmitter was the “run” station from which we could call CQ and contact any new callsigns on a given band. The other transmitter was a multiplier only station which was only allowed to work new multipliers (new DXCCs and CQ Zones) on a given band. We had both stations on the air simultaneously for a good portion of the contest period.

DXCC Progress for N1FD During The Contest Period
N1FD QSOs During The Contest Period

We operated on all of the contest bands from 160m through 10m during the contest. We mostly operated in Search and Pounce mode to focus on maximizing the number of DXCCs and CQ Zones worked. Search and Pounce mode also made it easier for the less experienced folks on our team to learn about contesting. We used a mix of data from the spotting cluster and tuning the bands to find and work stations. We did a bit of operating in Run mode (calling CQ) as well to help put additional QSOs in our log to boost our final score and to learn how to operate by calling CQ in a contest.

N1MM+ Logger Setup For Our DXCC Quest
N1MM+ Logger Setup For Our Contest Operation

We used the N1MM+ logger in a multi-op, networked configuration during the contest. This allowed us to share a single log between our two stations and to keep track of the multipliers (DXCCs and CQ Zones) that the combination of the two stations worked during the contest.

Final DXCCs Worked By The N1FD Team
Final DXCCs Worked By The N1FD Team (DXCCs worked are in Blue)

We worked a total of 108 countries in the contest and brought the total DXCCs worked by the N1FD callsign to 121.  This means that we worked a complete DXCC during a single weekend! We added 40 new DXCCs worked as a result of our contest operation.  Before the contest, our club call had 62 confirmed countries. We will need 38 more confirmations to qualify for the ARRL DXCC Award. We have received a total of 16 of the needed 38 new DXCC confirmations via LoTW as of the end of today!

We also gave our club a good start toward earning future 5-Band DXCC and DXCC Challenge Awards as we worked a total of 283 band-points during the contest.

Final CQ Zones Worked By The N1FD Team
Final CQ Zones Worked By The N1FD Team (Zones worked are in Blue)

We also made progress toward earning our CQ WAZ (Worked All CQ Zones) Award – we now have 33 our of 40 zones worked and 28 confirmed.

Our Final Claimed Score Summary
Our Final Claimed Score Summary For The Contest

We made a total of 607 QSOs during the contest for a claimed score of 588,208.  The actual score may be lower than this after the contest adjudication process completes in several months as deductions will be taken for any incorrect calls or exchanges. You can also see our results at the 3830 Score Rumor website.

Mike Rush, KU1V Working On Our DXCC In The Contest
Mike Rush, KU1V Operating In The Contest

Everyone involved had a lot of fun and learned some new skills. We are thinking about operating again as N1FD in the ARRL Sweepstakes Contest in November (Nov. 19-21). Please let us know if you’d be interested in joining the N1FD Team for this contest.

73,

Anita, AB1QB and Fred, AB1OC

Radio Amateurs Developing Skills Worldwide