Tag Archives: Guest Posts

Antennas, Field Reports, Guest Posts, Morse Code, News, Portable, POTA, QRP

KO4WFP: The Dipole Does It for Wheeler NWR

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Many thanks to Teri (KO4WFP) for the following guest post:

The Dipole Does It for Wheeler NWR (K-0161)

by Teri (KO4WFP) 

After my last activation, I was hankering to try the AX1 and Pacific Antenna 2040 trap dipole during the same activation for a comparison. Now, I know some of you are saying, “Well Teri, there would be no contest!” Yes, however, in the interest of learning first-hand, I headed to K-0161, Wheeler National Wildlife Refuge while visiting a friend, Glenn W4YES, and his wife in Decatur, Alabama.

Wheeler National Wildlife Refuge was established in 1938 as a wintering area for ducks, geese, and other migratory birds. It is a 35,000 acre refuge located along the Tennessee River near Decatur, Alabama. Today, the refuge attracts thousands of wintering waterfowl and cranes each year and is a winter home to the endangered whooping crane who first arrived in 2004.

I opted to set up in a parking lot on the north side of US Highway 67 which runs through a small portion of the refuge. As there were no picnic tables present, I chose a spot where the trees would shade me from the early morning sun while sitting in my Subaru Crosstrek. Since the last activation, I had given some thought as to how to set up better in the car. My code buddy Caryn KD2GUT sits in the backseat for POTA with one seat flipped down providing a ready-made table for equipment. Even better, I discovered the back of the rear seat in the Crosstrek has a rubber surface and I could secure the key to it with fun-tak!

Since the last activation, the more I worked with the Mini Palm Paddle, the more I realized I did not like it. It just felt too “squishy” for my taste and I had difficulty feeling the characters. Glenn has a solid state CW paddle by 9A5N he was not using. I worked with it a bit and really liked the stiffer feel. He removed the heavy base in which it was mounted and built a lighter base out of the back of a old diskette so I could take the key with me to Nova Scotia. (True ham radio – making use of whatever we have on hand to solve a problem!) I find the more I use this key, the more I like the feel of it.

This was Glenn’s first POTA activation and I was happy to have him along. We arrived around 8:05 AM and began setting up, first putting the AX1 on the roof of the car and then the trap dipole on a mast on a hitch mount given to me by Jack NW4TF of my local club. Continue reading KO4WFP: The Dipole Does It for Wheeler NWR →

Field Reports, Morse Code, News, Portable, POTA, QRP

A Rock Leads Teri on an Unexpected POTA Activation!

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Many thanks to Teri (KO4WFP) for the following guest post:

A Rock Leads to an Unexpected POTA Activation

by Teri (KO4WFP)

Sticks and stones may break my bones, but a rock can change the trajectory of one’s week.

Monday, while driving to the barn, a rock landed on my windshield leaving a chip in the glass. The soonest and closest appointment was in Bluffton, South Carolina. But having to work the appointment into my week, nixed my planned POTA activation for Wednesday at Wormsloe K-3725. However, I thought to check for any parks near Bluffton and yes, Victoria Bluff Heritage Preserve, K-9197, was within 15 minutes of my appointment. I could fit in an early activation before the appointment and put the AX1 to use for the first time. (Score!)

The drive Tuesday morning from Savannah, Georgia to Bluffton, South Carolina was scenic – lush, green foliage along the road interspersed with salt marsh and freshwater views.

The Victoria Bluff Heritage Preserve is 977 acres and has four miles of easy hiking trails. The warning on the SC Trails website about protective clothing & insect repellent for the large number of ticks that flourish in the preserve’s forest encouraged me to set-up in the parking lot. There were no picnic tables (my usual set-up) present so I planned on operating out of my car, a first for me.

However, how was I to mount the AX1 while sitting in my car since I had no tripod? I was still puzzling over this the morning of the activation when I remembered the Joby Gorillapod stand I purchased last year. Would the tripod mount for the AX1 work with it? Yes! It did. Continue reading A Rock Leads Teri on an Unexpected POTA Activation! →

Articles, Field Reports, Guest Posts, Morse Code, News, Portable, QRP, QRP Radios, QRPp

Guest Post: Lake Thunderbird (K-2792) with a homebrew transmitter!

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Activating (sort of) Lake Thunderbird (K-2792) with a homebrew transmitter

Sam Duwe WN5C

When I dove into radio a couple years ago a few sub-hobbies caught my attention: QRP, portable ops, CW, and homebrew. Of course, these all fit nicely together, but in my mind there was a huge leap between soldering an unun and a building a radio. But why not try? What’s the worst that could happen by melting solder and then sitting at a picnic table? This is how I built a simple transmitter and kind of activated a park.

The Michigan Mighty Mite

Nearly everyone has heard about the Michigan Mighty Mite (MMM), a QRPp transmitter popularized by the Solder Smoke blog. There are countless YouTube videos and posts across the internet. It’s very simple: a single transistor, a variable cap, a coil, a crystal and some resistors and a cap. Supposedly one can get up to half a watt of output (I couldn’t). But with a small purchase from Mouser one can oscillate. That seemed pretty cool.

I hadn’t touched an iron until I started playing radio. But I’ve been drawn to homebrew projects. I built a regenerative receiver last year which was very rewarding. I’ve also put together kits (a QCX mini and a TR-35). But my dream has always been to construct a transmitter/receiver combo, or a transceiver. I thought a good place to start was the MMM.

I built the transmitter based on the common schematic for the 40-meter band. The MMM is crystal controlled but I opted to solder in a socket and buy a handful of crystals, so I have the luxury of operating on 7056, 7040, and 7030 kHz. I made a few other improvements, too. The first was to build a low pass filter to attenuate harmonics. Second, although I haven’t finished it yet, the switch on the right will be to choose between multiple crystals. And third, I added a BNC jack to connect a receiver, with a transmit switch. When not in use the transmitter will dump into a dummy load. This receiver switching idea was lifted from the design of the MMM that QRP Guys produces.

When I tested the transmitter at home the best I could get with my charged Bioenno 3 Ah battery was about 300 mW output. The filter is reducing things somewhat, but maybe I need to look into a different transistor or rewind the coil. But I was able to get a 339 signal report from Illinois (no sked) in the midst of distance lightning crashes, so I had a little confidence going forwards. School is out for me this summer, so I decided to head to the park. Continue reading Guest Post: Lake Thunderbird (K-2792) with a homebrew transmitter! →

Accessories, Articles, Guest Posts, News

Guest Post: EmComm and FunComm!

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Many thanks to Scott (KK4Z) who shares the following post from his blog KK4Z.com:

EmComm and FunComm

by Scott (KK4Z)

As I have said earlier, I practice EmComm to prepare for natural or man-made disasters when normal means of communication fail. FunComm is pretty self-explanatory, it’s things I do for fun. Fun things may include POTA, Field Days (winter and summer), supporting bike rides, and other club activities. I always like it when I can blend the two together. When I participate in POTA either for a weekend camp-out or a day activation, isn’t it kind of a practice run for an EmComm event? I use the same antennas and most of the time the same radios. My equipment gets a good exercise and I learn more about how they operate under different conditions.

Recently, I bought a new camper, the old one wasn’t working well for the things I like to do. The new camper is so much better but not without its growing pains. I had to find a better way to use the radios inside the camper. To save words, here is a picture of what I have been using. It works okay but because it uses part of the bed, it made sleeping uncomfortable. After this last camp out when I woke up all sore and twisted feeling, I decided it was time to find a better way.

The new desk stacks the radio and power supply above the computer. This reduces the overhang on the mattress. The desk area for the paddle does overhang a little but sliding the desk to the right when not in use alleviates that.

The other thing I did was make a cut-out on the door side to make it easier to get my legs out. This works really well and does not impair the stability of the desk.

The last thing is the main desk is 30″ deep and the shelf is 20″ deep. This leaves plenty of room for the radios and enough room to slide the computer under the shelf if I need the desk space for something else.

Sitting behind the desk, the radio controls were easy to get to.

The desk is made from one sheet of 3/4″ plywood with (2) 1×3″x8″ boards. The stain was a can of Minwax I had laying around, I think it was Golden Oak.

Construction was simple, using hand tools found in most garages. It is not a piece of art, I don’t have the time. My philosophy is that “Perfection is the enemy of good enough”. The desk is glued, screwed, and nailed without any fancy joinery. If I waited until I had time to do a better job, the wood would still be at Lowe s.

I tried it out in the driveway and everything works and feels good. The radio is easy to get to and the computer is a little high but not uncomfortable. With the cut-out, it is easy to get in and out of the camper. The next test will be at the end of the month during my next camping trip. Hope to hear you out there. 73 – Scott

Articles, Field Reports, Guest Posts, POTA, QRP, SOTA

Getting To France With Detours: A SOTA/POTA/WWFF Triple Activation

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by Thomas (DM1TBE)

As I have written in my activation report for Klínovec, a summit in the Czech Republic, I am trying to activate places outside my home region DM, Germany – Low Mountains in SOTA or DA in POTA. With the May 1st being a public holiday, the long weekend provided a perfect opportunity for an activation a bit further away.

After a while looking around, I chose Brissetish Kopf (FL/VO-126) in France. The summit was close to the German border, hasn’t received much love with only 8 SOTA activations and was also a POTA spot for F-1697 Vosges du Nord Regional Park and WWFF Parc Regional des Vosges du Nord, FFF-0035. That promised enough QSOs for me and provided chances for chasers.

The small cluster to which the arrow points are the Vosges, actually the northern Vosges (Vosges du Nord). The cluster south of it are the higher part of the Vosges. The Vosges are a range of low mountains in Eastern France, which continues as Palatinate Forest on the German side of the border, with the highest summit being 1,424 m / 4,672 ft.

I started my journey quite early, leaving around 8am. During the drive I could not help but had to tease Thomas (K4SWL), who spent quite some time in France and, as far as I know, enjoyed it.

The French region Alsace, through which I had to drive to the Vosges, is quite interesting. The region was disputed over several hundred years between Germany and France and changed back and forth between the two. Many place names are still German, or sometimes a mix of French and German. After the World War II, the region returned to France – hopefully the last change.

I used Google Maps to drive to a parking place close to the summit, but my first attempt ended here:

Not sure why Google meant to show me this – thanks for the 30 minutes detour.

Roughly a half hour later, I arrived at Climbach, the small village next to the summit. Based on findings, the area is populated since the Middle Stone Age, that ranged from 280,000 to 25,000 years ago.

Continue reading Getting To France With Detours: A SOTA/POTA/WWFF Triple Activation →

Articles, Field Reports, Guest Posts, QRP, SOTA

Two SOTA activations in the Swabian Alb – And a broken JPC-7 antenna

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by Thomas (DM1TBE)

Intro

I live very close to the Swabian Alb (also known as Swabian Jura or Schwäbische Alb in German). The Swabian Alb is a mountain range in German region Swabia. It ranges from Bavaria in the northeast 200 km / 140 mi to the Swiss border in the southwest.

Thomas Römer, CC BY-SA 3.0, via Wikimedia Commons

The Swabian Alb is a high plateau, which falls slowly to the southeast but with steep cliff-like edges to the northwest. You can follow the northwest edge of the Swabian Alb by looking at the map of the SOTA summits at sotl.as.

The topology limits the possibilities to cross the Swabian Alb, so the course of the routes are more or less unchanged since thousands of years. I live close to an old Roman road. And where an important road was, there isn’t a castle too far away, since the medieval noblemen were quite keen to get its share from passing people and goods.

During the Cold War, important passes received mechanisms to place explosive charges. In case of an advance of the Soviets and its allies, it was planned to blow these roads up, as there was usually no alternative way around.

First Activation: Plettenberg

The Plettenberg (DM/BW-046) is a summit at the edge of the mentioned Swabian Alb, about halfway between Stuttgart and the Swiss border. It’s 1002 m / 3287 ft tall and has a quarry on top.

The quarry uses a ropeway…..

… to transport the stones to the plant.

The way from the parking place to the activation zone was rather short with 300 m /  1000 ft. Continue reading Two SOTA activations in the Swabian Alb – And a broken JPC-7 antenna →

Antennas, Articles, Guest Posts, News, QRP

Dale uses WSPR to test counterpoise orientation

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The CHA MPAS Lite

Many thanks to Dale (N3HXZ) who shares the following guest post:

Does your antenna counterpoise orientation matter?

by Dale (N3HXZ)

I am an avid SOTA and POTA activator and love field operation. I use a portable vertical whip antenna with a single counterpoise for my antenna system and have always wondered if orienting my counterpoise would provide some signal strength gain in a particular direction.  I decided to run a series of tests using WSPR to gather field data, and use statistics to answer the question:

Does one counterpoise orientation favor another in terms of average signal strength?

WSPR is a great tool for antenna testing. You can study various antenna configurations by making some WSPR transmissions and then checking the data on the WSPRnet database to see how well the signal was received at various stations located all over the world. You have to be careful in interpreting WSPR data though as receiving stations have different antenna and radio configurations, and the band propagation can vary rapidly at times. So how do you take advantage of all the data you receive from stations and draw some meaningful conclusions? I have found that using proven statistical theory in analyzing the transmitted signal strength received from individual stations can provide you results that you can confidently trust.

So what statistical algorithm is helpful?

For antenna signal strength comparison between two configurations, you can use an independent two-sample t-test with a one-tailed t-test evaluation. It sounds like a mouth-full, but it is quite simple. For our purposes, the t-test compares the average signal strength at a given receiving station from two different antenna configurations. The one-tailed test validates or invalidates the hypothesis that one antenna configuration produces an average signal strength greater or less than the other antenna configuration.

The testing requires that you run WSPR long enough to gather multiple reports at a single receiving station for both antenna configurations. Using the signal strength reports, you compute the average signal strength and the standard deviation of the signal strength over the sampled data points. Excel can easily provide that data.  With this information and the number of sample points for each antenna configuration (they can be different), you then run a calculation by hand or in Excel to compute the ‘t’ value.

This ‘t’ value is then compared to a critical value for the number of sampling points from a ‘Students t table”. If the ‘t’ value is less than the critical value you can confidently conclude that the hypothesis is false and therefore conclude that there is no significant difference in the mean value of the signal strengths between the two.  If the ‘t’ value is greater than the critical value you can accept the hypotheses that one antenna configuration produces a greater or less average signal strength than the other configuration. Continue reading Dale uses WSPR to test counterpoise orientation →

Accessories, Articles, Guest Posts, Portable, Reviews

Coax cables I used for SOTA/POTA – A horror story

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by Thomas (DM1TBE)

I think every portable operator thinks about their coax cables and how to use more light and flexible types. During the last few activations, I have switched from my rigid Aircell 5 to the lightweight and flexible RG316. I have bought a couple of different lengths, mainly from Chinese online sellers at AliExpress.

However, I had some hard to define issues like the vague feeling that I am not getting out as good as I should, or a changing SWR during an activation. So I thought I should check my cables before looking at other parts of my equipment.

My professional and educational background does not have anything to do with electronics, and I don’t have the equipment to measure the cable loss directly. But my goal was to check if the cables were faulty, not to measure the exact attenuation.

I have an SWR and Power meter from DJ9PK as per image below. It can measure PEP and has, according to the seller, an accuracy of +/-4 percent.   You can find more details about it here in German or here in English (Google / auto translated).

My KX3 with a CW paddle served as signal source. As large differences are easier to spot than smaller, I switched to the 10-meter band as the HF band with the highest attenuation.

I then measured a short cable with a very low loss, a 1 m / 3.3 ft RG213, which should have an attenuation of less than 0.1dB (excluding plugs).

I simply checked how much power came out at the other end of the cable. That value I have used as reference. This cable (and all others) was plugged directly between the KX3 and the power meter, no ATU involved anywhere. The power meter was set to measure PEP. Continue reading Coax cables I used for SOTA/POTA – A horror story →

Articles, Field Reports, Guest Posts, QRP, SOTA

SOTA in the Czech Republic – When everything goes wrong

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by Thomas (DM1TBE)

As I have mentioned in my two previous posts, I have visited my family on the other side of Germany. On the way back, I wanted to make a “tiny detour” and activate a summit in the Czech Republic. I like all kinds of numbers and statistics, and that includes my SOTA stats. My goal is not being number one or be in the top region somewhere, but seeing it progressing and developing satisfies me. Until July last year, the upper right pie chart was only light blue, i.e. I had only activated summits in region DM, Germany – Low Mountains. So I use every chance to push the light blue back.

sotl.as

After some concessions, my family agreed and the way back increased from 6 hours and 583 km / 362 mi to 8:30 hours and 732 km / 455 mi.

Route on Google Maps

On the drive to visit my family, I noticed that I forgot my wallet, so I had neither an ID card nor my driving license. In many regions of the world, it would be probably very difficult to cross an international border two times without papers. However, many countries in Europe have signed the so-called Schengen-Treaty, which led to the creation of Europe’s Schengen Area.

Camoka4, CC BY-SA 3.0, via Wikimedia Commons

The Schengen Area consists of 27 European countries with a population of over 400 million, who have abolished border checks. However, random inspections still happen. The worst case would be a control in the Czech Republic and the official requirement to go to the German embassy in Prague for new papers.
As expected, the border crossing was easy and it could easily been overseen.

If you missed that sign in the photo, you only note that the town names have changed to Czech, as Czech names are quite different. After the border crossing, the summit is just minutes away, and you can drive up to the very top – pretty convenient for a 10+3 points summit.

Derived from User:Rdc, Public domain, via Wikimedia Commons

The summit Klínovec (OK/KA-001), also known as Keilberg, is the highest mountain in the Ore Mountains, located on the border between the Czech Republic and Germany. With a peak reaching 1,244 me / 4,081 ft above sea level, Klínovec has been a popular destination for outdoor enthusiasts and tourists, and is the most important winter sports area in the region. The mountain has a rich history that includes mining activities for silver, lead, and tin in the dating back to 2500 BC, and it has evolved into a popular skiing and hiking destination in recent years, attracting visitors from both countries. According to reports, the peak has attracted people for hundreds of years, with the earliest observation tower erected in 1817. Continue reading SOTA in the Czech Republic – When everything goes wrong →

Accessories, Guest Posts, How To, Mobile, News

Scott builds a mobile desk for HF park-roving

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Many thanks to Scott (KK4Z) who shares the following post from his blog KK4Z.com:

Necessity is the mother of invention

by Scott (KK4Z)

Plato’s Republic he said that *our need will be the real creator* or the proverb as we know it today *necessity is the mother of invention*.  Recently, my friend Thomas K4SWL acquired a Yaesu FT-891.  During his YouTube video, he expounded on how much fun he had with it. It did indeed look like fun. During this time I was pondering about doing more day activations instead of overnights.  With the cost of everything still climbing, the need to conserve becomes apparent.  I thought an FT-891 might really be a great radio for these day activations. Then reality set in.

I already have a number of projects I am working on and misc things like maybe having to replace my old 33′ push-up pole, it was not in the stars nor was there a twinkle in my wife’s eye when I mentioned it. In reality, the IC-7300 is a great radio and does everything I need to do especially in the field. I don’t need another radio, I have three 100 watt radios and three QRP radios. I still wanted an easy setup for these one-day activations. I want to drive to a park, set up in a few minutes, operate, tear-down in a couple of minutes, and head for home or another park. I also wanted to make my day activations park ranger friendly. To me, that means trying to be inconspicuous.

I have two projects planned. The first is a desk for my truck. I am making a desk to sit over the center console and front passenger seat big enough to hold my IC-7300, a laptop and a CW paddle. My plan is to secure the desk to the truck and the radio to the desk. I also wanted to make this as cheaply as possible. I used stuff I had on the property such as a half sheet of plywood and some construction lumber. The only things I had to buy were some screws and eye-bolts, about 14 dollars worth.


The plywood was cut to 24 x 38.5 inches. The length covers the center console and front seat while still allowing me to get to the heat/AC controls. I gave the corners a generous radius and I broke the edges with a router. On the underside, I used a 2 x 12 to make a spacer for the center console where the cup holder is and a leg for the other side over the passenger seat. The spacer is glued and screwed to the desktop but the leg is not attached. This is to make it easier to store. I made a socket for the leg using 2 x 2’s. It’s probably easier to look at a picture than me to try to explain. I added eye rings to the rear of the desk and use a bungee cord to secure the desk to the passenger seat. The only other thing I did, sprayed the top with polyurethane. Note. I am not a carpenter or cabinet maker. I use rough hand tools to get the job done and I am often making do with what’s on hand or what’s the cheapest way to do it.

Continue reading Scott builds a mobile desk for HF park-roving →