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Sometimes with DX, it’s better to be lucky than good. Well, I really shouldn’t say that.  I know nothing of being good when it comes to DX, but I sure can relate to lucky.

Band conditions were good today, and I went out to the Jeep at lunchtime to find 15 Meters hopping!  I heard a huge pileup around 21.023 MHz and I think it was for JA7SGV/6V in Senegal.  He was loud here in NJ, so despite the pileup being furious, and despite having worked Senegal on another band, and because I’m an optimist at heart, I decided to give it a go.  I turned on the “Dual Watch” feature on the KX3, hoping that I would be able to figure out where he was listening.  After listening for a goodly bit, it became apparent that I was not hearing the same stations that the DX station was going back to. So I hoped for the best and started throwing out my call at 21.025 MHz. It seemed as good a place as any to start.

Then all of a sudden, my call comes back to me.  But it wasn’t from the ear bud tuned to 21.023 MHz, but instead from someone transmitting on 21.025 MHz.  I quickly turned off “Dual Watch” and deactivated the split function and twirled the main VFO up to 21.025 MHz.  I thought just maybe it was someone who heard my call sign in the pileup, recognized it, and wanted to say “Hello”.  A half second later, when I got up to 21.025 MHz, the station was still calling me and sending out “W2LJ 579 TU BK” waiting for an acknowledgement.  Obviously, this was NOT someone wanting to say “Hello”. So since the station was loud, auto-pilot and habit kicked in and I sent back “DE W2LJ TU 599 NJ BK”.

It turns out that it was MJ0ASP, located on the Island of Jersey.  A DXCC entity that I have never worked before at all, let alone via QRP!  How cool is that!  Tried for Senegal, but got a brandy new one, instead (albeit by accident!). Add to the fact that New Jersey was named for the Island of Jersey, so there’s a little historical connection there, too..  My hat is off to Elecraft, because if it weren’t for the “Dual Watch” feature on the KX3, I might have missed Jersey entirely.  A very good day on 15 Meters, indeed, as a little while later, I also worked Luca IK3VUT in Italy and Pep EA6FG on the Balearic Islands

I was listening for K3WWP and KC2EGL on 40 Meters, as they were scheduled for another Parkpedition today.  I didn’t hear anything on 7.041 MHz, so I broke down, packed up and headed in. Checking e-mail, it appears that it was raining in Kittaning, so John and Mike put lift off on hold for about an hour or so.  Can’t blame them. Who wants their equipment to get wet?

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

Hi all,

The Lydford from Walford

I am in the process of updating radiokitguide.com.  If you can think of any new kit sources that I haven’t covered yet, please leave a comment here.  I am looking for RECEIVER, TRANSMITTER, and TRANSCEIVER  kits.  I will cover accessories at a later date.  If you know of a spectacular source of accessory kits though, send it along anyway.  I am adding a couple of new sources, and making changes to YouKits, Small Wonder Labs (goodbye), TenTec, and several others.  Thanks in advance for your help!

Conditions seem to have been pretty good on 10m over the last day or two. Yesterday, as I was driving back from the convention the band was buzzing! I concentrated on 29MHz AM and was interested to hear N4ZED coming in from Georgia. I called but although Ken could hear a G there he wasn’t able to pull me out. Hardly surprising given my low power. I was surprised he heard anything at all,

This evening AM was quiet as I was heading home, but the SSB portion was lively. I managed a quick fire contact with K8CW which I was happy with, running 10W or so to the whip.

This is really something. Now I can hear actually John N8ZYA my fellow blogger. I am always looking out for well-known hams out there. John is one of them, so far I was not successful. Thanks to NG9D for sharing this video.

10 meter was very good yesterday. I heard Greenland, which I do not hear every day. The JT65A portion of the band was very crowded. Instead of the PSK31 portion. A new trend?

With JT65A I worked TA2EM on 10m which was wide open. With CW I worked: K9LJN, A45XR and VE3EN.

Whilst leaning out of the car window and manually turning my decorators pole (complete with 70cms antenna) and waiting for a break in a UKAC (VHF Contest) QSO I thought that there must be a better way of doing this.

The antenna weights way less that 1Kg and the decorators pole has a perfect coarse thread to it so it shouldn’t be too hard to make up a simple attachment with a stepper motor on it, driven of course by the mighty Arduino and its motor shield

Although I’ve not put one of these together and its a bit of a pipe dream whilst work keeps sending me all over the place I’ve seen more that my fair share of articles that use the motor shield to drive stepper motors (guessing its some kind of H bridge / relay arrangement). So I’m guessing (again) that the bare bones of the system could be pulled together over winter. ready in time for next years UKAC series.

I enjoy the UKAC series but running /P has its unique problems up here in West Cumbria. As I type now the winds are getting stronger and we expect the gale force variety over the weekend. Even when we’re not being blasted with salty Irish Sea venturing out /P means that having a car window open in the winter on the top of a hill is ‘challenging’.

So the challenge is on me now to come up with something now that my work project is attempting to shift from ‘Madness’ to simply ‘Frenetic’ between now and November and possibly simply ‘Stressful’ in December.

Once that’s done…hah ha…I’ll concentrate on the single boom  6m / 2m /70cms antenna I’ve been thinking about that means I don’t have to crawl around in the dark with loads of bits in the car.

Still if someone’s done it already, please put me out of my suspense.

It’s always nice to find that other people’s findings match your own. PA0RDT is famous for his design of the mini-whip, a very small but effective long- and medium wave antenna. Roelof found that the magnetic component of a radio wave could more easily go through obstacles, while the electrical component was more contained within a closed space, like a house. This means that the electrical component of noise generated by appliances in the house stays inside – mostly – while the magnetic part travels outside the walls. Thus his mini-whip design picks up the electrical component only and amplifies that. If the antenna is placed some distance from interfering obstacles it will result in a strong, but relatively noiseless signal. I build one and can say it really works.

But amplification comes at a price: IM and overload. Passive loop antennas have non of the afore mentioned problems. Since the beginning of my radio days I have always had a one metre square loop antenna for MW and LW and deep in my heart I longed for one. So I build one again, but this time bigger: 180 cm square with the corners clipped. Tuning is done remote with a BB112 varicap. The circuit was once published by the Benelux DX Club and I’ve had it for over 25 years, but never build it to this day.

Because of bad weather I could only put it up last weekend and boy, what was I disappointed. It seems it picks up all the television noise from the whole neighbourhood, with added noise from within my own house. The mini-whip is clearly better than the loop, so PA0RDT is right. But using another laptop power brick helped a bit and after firing up Argo it seemed that despite the noise the loop was still proving itself useful.

The loop tunes from 136 kHz to just above 400 kHz, which covers most of the NDB frequencies. Even though long wave beacons are on the decline there are still a lot of them. I heard some 30 new ones over the weekend, both in the daytime and at night. Argo is a great tool, sometimes beating my ears in picking up signals. Here some screen shots.

Locator “O” on 201 kHz and PQ on 202 kHz, both unidentified.

An odd one heard on 220 kHz: BRBA5. Notice that the dash in the letter “R” is longer than the other dashes. Ears won’t notice this, but with Argo you can see it.

Three beacons on the same frequency of 380 kHz: LM, OB and sandwiched in between YU from Hualien (Taiwan’s east coast).

NDBs are fun to DX, but my goal is to do some 2200m DX. Without any voltage applied to the varicap the loop is tuned to 136 kHz, which means I can leave it on all night and hope that I can detect some signals from Japanese hams, or maybe the Philippines. Unfortunately Chinese hams are not allowed to use 2200 meters and I don’t know of any Taiwanese hams operating this low. Help! I think I am becoming “low-nely.

Here’s a design for a 1 MHz amplitude modulated (AM) transmitter. I’ve been looking a while for something like this, a simple short range AM transmitter for the medium wave band, as I needed something for demonstration of my collection of old radios.

The result is the AM transmitter shown here in an Altoids tin on top of a Radionette Kurér radio. This is a portable tube radio from the 1950’s. Several hundred thousands were produced, and it was exported from Norway to 60 countries. It is still popular among collectors.

The transmitter is as simple as it gets. The heart of it is a 1 MHz crystal oscillator in a can. Its 5 Volt power is modulated via an audio transformer, one taken from the output of a transistor amplifier (primary 147 ohms – secondary 3 ohms). I drive the modulator from my cell phone into the low resistance side of the transformer and get good audio when the phone’s volume is set to maximum.

The design was inspired by one from Instructables, but mine also has a 78L05 5 Volt voltage regulator and a red LED in series with the power supply. It indicates that the battery is plugged in. In total the transmitter draws 4.4 mA at 9 Volts. The input power to the oscillator is less than 5 Volts * 4.4 mA or in the order of 20 mW. The power output is just a fraction of that. I have tested it with a 1.5 m wire hanging down behind the built-in frame antenna in the back of the radio with good results.

This is really just a modulated marker transmitter as I have briefly described on this blog before, and the square wave will have harmonics of 1 MHz over the entire short wave band. Some of these frequencies may propagate really well, so if used with a longer antenna, it should really have an output low pass filter to prevent that.

I’m not totally happy with this design, despite its simplicity, though. If I could, I would rather like to transmit in the long wave band at 216 kHz. This is the old frequency of the Oslo transmitter which ceased operation in 1995. As a member of the Norwegian Radio Historical Society, I am allowed to use that frequency with a transmitter input of 0.5 W for demonstration purposes.

For other frequencies, one simple alternative is a standard canned oscillator at 1.288 MHz. I also believe some of the Silicon Labs oscillators can be used in order to get an adjustable frequency, but I haven’t tried that myself.

But until I find a suitable frequency source at 216 kHz, I’ll stay with the 1 MHz alternative at a mere 20 mW. It is in line with the best principles of KISS (keep it simple stupid) or with Occam’s principle : “It is vain to do with more what can be done with less“, i.e. the QRP philosophy.