Category Archives: Field Radio Kits

Dean’s Compact KX2 Field Kit in a Pelican 1150

Many thanks to Dean (KG7WGX) for sharing the following article about his portable field radio kit, which will be featured on our Field Kit Gallery page. If you would like to share your field kit with the QRPer community, read this post.


KX2 Field Kit

by Dean (KG7WGX)

I have used Pelican boxes in the 1150 size for years for transporting my KX3, PX3, keys, and a 10Ah battery. A few months ago, I tried to devise something that would let me take just the KX2 for “pack it in” operations, in one of the 1150 boxes.

I wanted the radio, battery, earbuds, paddles and a mini-mike to fit in the waterproof box. Whatever antenna I decided to take could be packed in a stuff bag separately. This would also apply to a kneeboard & chair (if I wasn’t going very far.)

The first picture shows the antenna bag, 20ft mast and the Pelican box:

Tbe second picture shows the components laid out:

The third picture shows how the battery, earbuds, paddles and mini-mic fit inside the Pelican box:

Gear links:

Note: All Amazon links are affiliate links that support QRPer.com at no cost to you.

Notes:

  1. Balun Designs standard RF connectors are SO-239 but a BNC connector is available for small additional charge. The 9130 has a hole for a support line, so I attached approx 10 ft of paracord to lift it above ground level.
  2. Guy line collar attached to Explorer 20 mast at section “overlap” region with epoxy. Guy line ring has 3 paracord lines and is rigged before extending mast. Guy line collar keeps guy line ring from moving down mast. A PVC end cap with a stainless machine screw serves as an “anti-kickout” support for the mast base. Each guy line has a line tightener.
  3. Shure SE112 earbuds have a rt-angle 3.5mm connector.
  4. M0JKS mini-mike has a TRRS connector on the mike, so the user can supply whatever length/connector style he prefers. 3.5mm audio cables are available with a straight TRRS on one end and a rt-angle TRRS on the other (to comply with Elecraft recommendations to reduce lateral force on the connectors.)
  5. Bioenno has changed the BLF-1203AB “shape” from rectangular to rounded edge, but the dimensions remain the same.

The total weight (with the mast and EF Random antenna) is a few ounces over 7 lbs, so this isn’t a Mountain Topper.  😉

73, Dean
KG7WGX

Steve’s MTR3B-V4 Field Kit in a Rothco Shoulder Bag

Many thanks to Steve (KV4AN), who shares the following article about his portable field radio kit, which will be featured on our Field Kit Gallery page.  If you would like to share your field kit with the QRPer community, read this post.


KV4AN’s MTR3B-V4 Field Kit

by Steve (KV4AN)

The convergence of Solar Cycle 25, lots of great new equipment offerings, many active participants in Parks on the Air (POTA), Summits on the Air (SOTA), and compatible family outdoor activities make this a great time to be a portable High Frequency (HF) QRP ham radio operator.  To take advantage of this happy situation, I was recently able to purchase a MTR3B-V4 “Currahee” Mountain Topper transceiver, shown in figure (1).  The MTR3B-V4 is a miniature three band (40, 20, and 15 meters) CW only QRP transceiver made by LNR Precision.

Figure 1.  MTR3B-V4 “Currahee” QRP Transceiver.

Naturally, I had to form a kit around the new radio.  My three goals for the kit were: small size, lightweight, and self-contained.  Let’s see how I did.  You can comment below if I left something out or if there’s a better choice.

The kit consists of the following items, as shown in figure (2)–links to these items are at the bottom of the page:

Figure 2.  MTR3B-V4 Kit.
  1. MTR3B-V4 “Currahee” Transceiver – 40, 20, and 15 meter QRP CW Transceiver.
  2. Custom Faceplate Cover – A practical and reasonably priced custom faceplate protective cover.   I accidentally ordered the cover for the previous version of the radio, but Joshua had no problem with me changing the order to the new one.
  3. Morse Code paddle – This is a reasonably priced paddle with a fairly good feel that I had lying around when the capacitive knobs didn’t work out.  I plan to replace it in the future with the CW Morse SP4 POTA/SOTA N0SA design paddle, which is smaller and field proven.
  4. 3.5mm Stereo Cable – A 1.5 foot, 3.5mm to 3.5mm stereo (TRS) cable.
  5. Koss Earbuds – Nice quality stereo earbuds.
  6. Earbud Cord Organizer – I hated to add the extra item, but I got tired of untangling the  wires of my earbuds.  This clever item has solved that problem and is color coordinated with the slick line.
  7. All-Weather Notebook – All-weather notepad for copying QSO information in the field.
  8. Miniature Pen – This is a miniature pen that says it writes on waterproof paper.  It will also write upside down, although that may not be a feature you need during normal activations.
  9. Koss In-line Volume Control – An in-line volume control for use with the earbuds.  The MTR3B-V4 has a rudimentary volume control, primarily used to set the maximum volume level.
  10. Battery Pack Pouch – A small pouch that perfectly holds the battery pack and keeps all the components together and protected.  If you use Icom BP-307 or BP-272 battery packs, they fit perfectly too.
  11. Battery Cell Holder – An eight “AA” cell holder with a 9V-style clip.  Eight “AA” NiMH batteries will provide a nominal 9.6V to the transceiver.
  12. AA NiMH batteries – Eight 1.2V “AA” NiMH 2800 mAh Low Self Discharge (LSD) battery cells.
  13. 9V Snap Clip – These are good quality 9V snap connectors that also have the coaxial power connector required by the MTR3B-V4 already attached.  They are more durable than the ones with exposed thin red and black wires.
  14. Coaxial Adapter – SO-239 to BNC adapter for use when using other antennas with coaxial cables which have a PL-259 connector.
  15. Reliance EFHW “Bugout” Antenna – A very small and sturdy 40, 20, 15, and 10 meter End-Fed Half Wave (EFHW) resonant antenna.
  16. Slick Line – High visibility slick line, which ties to the arborist throw bag to get the antenna into a tree and then suspends it.
  17. Arborist Throw Bag – A well-made arborist throw bag with a good all-around weight.
  18. Gerber Mullet Keychain – An all-in-one minimalist tool kit.  Better than a sharp rock, as they say.
  19. Rothco Shoulder Bag – A military-style shoulder bag, just large enough to hold all the kit components.
  20. Battery Charger – The battery charger (not shown) is an eight cell NiMH charger.  It does not fit in the shoulder bag and is left at home.

Of course, it all had to fit in a tacticool bag.  I selected the small Rothco Excursion Organizer, The shoulder bag, shown in figure (3), has all the items from figure (2) in it (trust me).  Use the orange pen as a reference for the size of the bag.  Clipped to the “D” ring on the left side is the Gerber “tool kit”.  The pocket on the front left has the CW Morse paddle, the pen is in its place, and the zippered pocket on the right has the earbuds.  The back zippered pocket has the antenna and battery pack, and safely nestled in the main area is the MTR3B-V4 and an arborist throw bag.  There is a zippered sleeve in the main pocket that contains the cable for the keyer paddle, an adjustment Allen wrench, and the SO-239 to BNC adapter.

Figure 3.  MTR3B-V4 Shoulder Bag.

Conclusion

One thing you may have asked yourself is why I included a Morse Code paddle when the MTR3B-V4 has a set of capacitive touch knobs.  The answer is simple – they didn’t work for me.  I really wanted them to, but the pad of my thumb will not activate the “dit paddle” without moistening it first.  Even then, I have to press the knob hard at a point almost to the joint, which is not a natural code sending motion or feel and results in very sloppy code.

Another item I purchased, but decided not to use was a pair 9V 500 mAh Lithium Ion rechargeable batteries.  The voltage of this battery right off the charger is below the specified input voltage for the MTR3B-V4.

The battery is the area in which I am most concerned.  I’m concerned that the 9.6V NiMH pack may not provide enough voltage over an activation to keep the voltage above the specified minimum voltage of 9V.  I may have to go to a 12V LiFePO4 battery, but that will not fit in the current shoulder bag.  I may have to go with a larger bag or use a MOLLE system where I can strap together several pouches.

I think I’ve came close to achieving my three goals of: small size, lightweight, and self-contained.  I’ve not completed an activation with this kit yet, so I’ll see how it all works together in a few weeks.  I’m also looking forward to reading your comments and suggestions.

72,

Steve

KV4AN

Gear List Links

[Note: Most Amazon and CW Morse links are affiliate links that support QRPer.com at no cost to you.]

  1. MTR3B-V4 “Currahee” Transceiver (MTR3B V4 Currahee Mountain Topper)
  2. Custom Faceplate Cover (LNR MTR-3B-v4 Currahee Magnetic Protective Cover – Tufteln)
  3. Morse Code paddle (Black Pocket Double Paddle Morse Code Key – cwmorse.us)
  4. 3.5mm Stereo Cable (Amazon.com: Aux Cord 1.5ft, 3.5mm Aux Cable – Nylon Braided Audio Cable 3.5mm Male to Male AUX Cord Compatible with Car,Headphones, iPods, iPhones, iPads,Tablets,Laptops,Android Smart Phones& More (1.5FT) : Electronics)
  5. Koss Stereo Earbuds (Amazon.com: Koss 191651 KE5 Earbuds (Black) : Electronics)
  6. Earbud Cord Organizer (Amazon.com: ELFRhino Cord Organizer Earbuds Holder Earphone Wrap Earphones Organizer Headset Headphone Earphone Wrap Winder Cord Manager Cable Winder Green : Electronics)
  7. All-Weather Notebook (Amazon.com : GLORYFIRE Waterproof Notebook Tactical All-Weather Spiral Memo Paper Notepad with Waterproof Grid Paper for Outdoor Activities Recording 3″x5″ (5pcs) : Office Products)
  8. Miniature Pen (Amazon.com : Tombow BC-AP54 Pressurized Permanent Ballpoint Pen (Can Write on Wet Paper/Back), Air Press to Squeeze Ink Ink, 0.7, Orange : Rollerball Pens : Office Products)
  9. Koss In-line Volume Control (Amazon.com: Koss 155954 VC20 Volume Control, Standard Packaging, 39-Inch Cord, Compatible with Cell Phones and Headphones : Volume Control: Electronics)
  10. Battery Pack Pouch (Amazon.com : TRIWONDER Tactical Cigarette Pouch Molle Small Military Bag Battery Cigarette Case EDC Utility Card Holder Lighter Slot Mini Cigar Waist Pack (01 Green – 2 Pack) : Sports & Outdoors)
  11. Battery Cell Holder (Amazon.com: QTEATAK 2Set 8 x AA Thicken Battery Holder with I Type Wired Battery Clip Standard Snap Connector : Electronics)
  12. AA NiMH Batteries (Amazon.com: WENJOOP Rechargeable AA Batteries, 2800mAh High-Capacity NiMH AA Rechargeable Battery Long-Lasting Power, 8 Pack Double A Batteries Size for Household and Office Devices – 1.2 Volt Low Self Discharge : Health & Household)
  13. 9V Snap Clip (Amazon.com: CHANZON UL Wire 9V Battery I-Type Power Supply with Center Positive 2.1mm x 5.5mm Male DC Connector Holder Clip Converter, 5 Pack for Arduino, LED Strip : Electronics)
  14. Coaxial Adapter (Amazon.com: Ahoaepy 2PCS UHF to BNC Adapter, Low Loss SO239 Female to BNC Male Coaxial Cable Connector Adapter for CB Radio,Radio,Antennas.Extension Coax Cable : Electronics)
  15. Reliance EFHW Antenna (EFHW Bugout 56:1 40-10M Antenna – Reliance Antennas)
  16. Slick Line (Amazon.com : LiteOutdoors Guyline & Tensioner Kit – 1.8mm Diameter – 60 or 100 feet – Ultralight Reflective Tent Cord, Lightweight Non-Slip Cord Adjusters. Camping, Hiking, Paracord : Sports & Outdoors)
  17. Arborist Throw Bag (Amazon.com : SOB Outdoor Throw Weight Bag 250g Arborist Durable Climbing Rope Bag Multi Throw Bag Tree Rock Spelunking : Sports & Outdoors)
  18. Gerber Mullet Keychain (Gerber Gear Mullet Keychain – Multi-Tool Keychain with Pry Bar, Bottle Opener, and Wire Stripper – EDC Gear and Equipment – Stonewash – Amazon.com)
  19. Rothco Shoulder Bag (Amazon.com: Rothco Excursion Organizer Shoulder Bag, Olive Drab : Clothing, Shoes & Jewelry)
  20. Battery Charger (Amazon.com: EBL AA AAA Battery Charger, 8-Bay Individual Charger for NiMH NiCD Rechargeable Batteries with AC Plug Fast Charging : Electronics)

 

A Strong Case for the (tr)uSDX: Jamie’s Perspective

Readers, there’s a bit of a backstory to this guest post by my friend Jamie (AA4K). During the W4SOTA campout in October 2023, Jamie showed me his favorite field radio: the (tr)uSDX. I’ve used the (tr)uSDX for a couple of activations, but I’ll be honest—I haven’t exactly shown it a lot of love. I’ve even complained about its audio and receiver performance in the past. Jamie, on the other hand, really enjoys using his and makes a solid case for it as a field radio.

Jamie showing me his (tr)uSDX during the W4SOTA campout.

I asked if he’d be willing to write a guest post for QRPer, and he agreed (eventually!). When I saw him at Hamvention this year, he told me the article was ready—and in true form, he sent it to me via Winlink… using his (tr)uSDX.


A Case for the (tr)USDX

by Jamie (AA4K)

Introduction

There are many factors that must be considered when choosing a field radio. How big and heavy is the radio? How hard is it to repair or replace the radio if it becomes damaged or lost? How hard is the radio to operate? How power-efficient is the radio? Does the radio have the desired/required modes and features? Of course, the most fundamental question is, “Does the radio work?” I will try to answer these questions as I lay out… a case for the (tr)USDX as perhaps an almost perfect field radio.

The last two contacts on this page were with my friends Carlos (KB4CO, now AE2W) and Thomas (K4SWL).

How big and heavy is it?

The first question is an easy one. Aside from small home-brew radios such as K6ARK’s “Choking Hazard”, there isn’t a smaller or lighter commercially available radio out there that I am aware of. The (tr)USDX measures 112 x 61 x 50 mm (I trimmed the encoder post and used a lower profile knob), and weighs 5.3 oz, or 151 g. The next closest currently available commercial radio is perhaps the QRP Labs QMX. This radio is very comparable in size (110 x 64 x 38 mm) and cost, but it does weigh more at 7.3 oz, or 207 g. The more rugged metal case probably plays a big part in the weight difference.

(tr)USDX with a modified case I designed to use the radio as the antenna winder.

How hard is it to replace or repair it?

The (tr)USDX is often sold as a kit for about US$86 (+$20 for the case) [QRPer affiliate links]. Any repairs should simply involve desoldering affected components and replacing, or possibly just updating the firmware. I am a relative noob when it comes to kit building and this kit is honestly not very difficult to build… about one day. The instructions and support videos provided by the hardware developer, Manuel DL2MAN, are very thorough. I learned a lot about radios from building the kit. If you have no interest in kit building, the assembled radio can currently be purchased from Amazon for US$138, complete with a case. Whether purchased as a kit, or already built, the band pass filters on the radio board will need to be tweaked to get the most out of your radio.

How hard is it to operate?

The (tr)USDX only has 4 buttons including the rotary encoder: Menu, Encoder, Enter, and PTT. The Menu and Encoder cover the majority of the adjustments, and most of the time I don’t use the Enter and PTT buttons. The PTT functions only as a ptt or cw key depending on the mode (yes, if your key breaks mid activation, you have a built-in backup key). The single-layer menu system is simple to scroll through, and the most commonly used items are near the front of the menu.

The most challenging aspect of operation for some people is the tiny OLED screen which gets obliterated in bright light. Reading glasses do help, although when you become familiar with the menu are not as important. I would love to see a version with an e-ink display and, more importantly, a push-button wheel rotary encoder (to remove the protruding knob).

How power-efficient is it?

This radio sips power. I tested the radio I built using a LiFePO4 battery that supplied 13.56v. The current draw on receive is 66.1 mA, and 570 mA on CW keydown into a dummy load. A properly tuned (tr)USDX delivers about 5w on each of the five bands when fed ~12v. A set of three 18650s in series will provide the proper voltage and power the radio through many activations.

Does the radio have the desired/required modes and features?

The (tr)USDX is not for princesses. It is a minimalist’s radio. But if you start from the perspective of an ultralight backpacker who has to justify every gram in their kit, this radio checks all of the boxes. It is a five band radio (Low, Classic, and High band models available). It is capable of doing voice, cw and digital modes. Thanks to a beta update from the firmware developer, Guido PE1NNZ, this radio will interface with a computer without requiring a soundcard. One of my favorite features of the radio is the built-in SWR meter. With the SWR feature enabled in the menu, just put the radio in CW mode and press the PTT to find out if your radio is happy with the current antenna arrangement.

This photo was taken while sending the text of this article via Winlink to Thomas, K4SWL.

Does the radio work?

Although my total activation count is nowhere near as high as many of you, I have used the (tr)USDX for a majority of my successful POTA (156 as of this writing) and SOTA (72 as of this writing) activations. My confidence in this little radio was demonstrated when I used it on an ATNO activation of Admiralty Island National Monument (US-4537) in Alaska.

Conclusion

One reason why I like to participate in SOTA and POTA is that it gives me an opportunity to practice field radio deployment and operation with the goal of being ready to communicate anywhere and anytime. This level of readiness means that I have the necessary equipment with me all the time. For me, the (tr)USDX is my EDC (every day carry) radio. It can bounce around in my backpack (in its protective case, of course) and be ready to deploy if needed. If it were to get lost or broken, I can fix or replace it easily. And I find it to be easy enough to use with the understanding that it isn’t a luxury radio.

The author at ~11,000’ in Uncompahgre National Forest.

Video

Click here to view on YouTube.

(tr)uSDX Winder Case:

Click here to download the print file for Jamie’s the modified (tr)uSDX case.

Field Radio Kit Gallery: KO6BYB’s Compact Watertight Elecraft KX2 Kit

Many thanks to Cameron (KO6BYB), for sharing the following article about his portable field radio kit, which will be featured on our Field Kit Gallery page. If you would like to share your field kit with the QRPer community, read this post.


Elecraft KX2 Field Kit

by Cameron (KO6BYB)

I wanted to share a tiny KX2 kit I made to fit the Seahorse SE56 (QRPer affiliate link) case. Just upgraded to my General and finally got the HF transceiver of my dreams. Haven’t made it out to the field since I got it last weekend, but I had some spare time (that I should have been sleeping) and whipped this up. Fits basically a whole station in the case:

Components:

  1. Seahorse SE56 watertight case
  2. Elecraft KX2
  3. KXPD2 paddles
  4. Microphone
  5. KXBT2 Battery
  6. AX2 antenna + 40m extender
  7. Ground wire
  8. Pen

If you’re only going to do CW, maybe there’s something clever to put in the place of the mic, but I am still working on my Morse. Slowly but surely.

Inserts can be downloaded on Thingiverse:
https://www.thingiverse.com/thing:7010681

W8TMI’s Elecraft KH1 Field Kit

Many thanks to Tim (W8TMI), who shares the following article about his portable field radio kit, which will be featured on our Field Kit Gallery page.  If you would like to share your field kit with the QRPer community, read this post.


W8TMI’s Elecraft KH1 Field Kit

by Time (W8TMI)

My Elecraft KH1 field kit is split into two parts: the bag provided with the Edgewood package and a separate bag for added functionality. The Elecraft bag is set up to venture out by itself without anything else required for an activation. The additional bag provides a longer random wire antenna and the ability to get it up into a tree, which increases its gain over the stock whip antenna.

[Note: Most Amazon links are affiliate links that support QRPer.com at no cost to you.]

Additional Photos

2mm bullet adapters for counterpoise wires

Primary KH1 bag

Storage setup

Antenna bag

Eric’s Go-To Low-Cost, Self-Supporting Antenna System for POTA

Recently, @JasonMartinRF left a comment on my YouTube channel mentioning his excitement about getting on the air with CW but also his concern about the high cost of antennas—especially self-supporting options that don’t require trees. His comment resonated with me because many operators face the same challenge when setting up a portable station, particularly for POTA or other field operations.

I immediately thought of my friend Eric McFadden (WD8RIF), who has extensive experience with lightweight, affordable wire antennas that don’t rely on trees for support. Eric has long used a homemade end-fed random wire (EFRW) antenna paired with cost-effective mast solutions, making it a great choice for portable activations. I asked him if he’d be willing to share the details of his setup, and he generously wrote up the following guide.


A Budget-Friendly Self-Supporting Antenna System for POTA

by Eric (WD8RIF)

Because I’ve long used low-cost homemade wire antennas for POTA, and since I usually don’t rely on trees to support these antennas, Thomas asked me to describe an antenna and support systems I often use for my POTA activations.

My “Go-To” antenna for POTA is a 28½’ end-fed random wire (EFRW) antenna with three 17’ counterpoise wires. This antenna covers 40m through 6m (and sometimes 80m) and is constructed from inexpensive speaker wire which can be purchased at big box stores in 50’ and 100’ spools. This two-conductor cable can easily be split into two conductors and the thick insulation helps prevent the finished antenna from tangling.

The idea behind the EFRW antenna is that the length of the antenna is not close to a ½-wavelength on any frequency for which it will be used. The EFRW is not resonant on any band of interest and, thus,  it requires the use of an antenna tuner (ATU).

The benefit of the EFRW is that it can be stealthy and lightweight, it can be relatively short when compared to simple resonant antennas, and it can support operation on multiple bands. It is true that this antenna requires the use of an ATU, but even an inexpensive manual tuner can be used for this purpose.

To construct my version of the EFRW, split the speaker wire into two separate conductors. Cut one conductor to a length between 28½’ and 29’ to create the radiator. Cut three more conductors approximately 17’ long. Strip a ½” or so of insulation off of one end of each of the four wires. If you wish, install banana-plugs on the stripped end; I put a green, red, or orange banana plug on the radiator and “stackable” black banana plugs on the three 17’ counterpoise wires so I can easily attach all three of them to a single “ground” post. Install an insulator of some sort on the far end of the radiator wire, or create a small loop on the far end of the wire using a knot or a nylon wire-tie for hanging the antenna. (I use military buttons as  insulators on my field antennas, and I often use large paper clips to hang the wire to the top of my mast.)

The speaker-wire end-fed random wire antenna
The speaker-wire end-fed random (EFRW) wire antenna. The three 17′ counterpoise wires are on the left; the 28½’ radiator is on the right.

 

You can connect the radiator and counterpoise wires directly to your ATU-equipped transceiver or external ATU using a simple binding-post adapter or, preferably, a 4:1 unun. No coaxial feedline is needed or, in fact, recommended.

LDG 4 to 1 unun and simple binding-post adapter
An LDG 4:1 unun (left) and a simple binding-post adapter (right).

I regularly use a simple binding-post adapter when I’m in the field with my Elecraft KH1 or KX2 field kits. I use a homebrew 4:1 unun when I’m in the field with with my Elecraft KX3 field kit. I use a commercial LDG 4:1 unun (link) when I’m in the field with my Yaesu FT-817ND field kit. (I should note that my KH1, KX2, and KX3 are each equipped with internal ATUs. The FT-817ND doesn’t have an internal ATU but I use a no-longer-available LDG Z-11 ATU with it when I deploy a non-resonant antenna.)

In the field, I suspend the 28½’ radiator as a vertical, as a sloper, or as an inverted-vee, and I lay the three 17’ counterpoise wires directly on the ground, arranged as symmetrically as possible while trying to avoid trip-hazards. (If space is limited, I might lay down only two counterpoise wires or, maybe, even just a single counterpoise wire.)

I usually support the EFRW with a 31’ Jackite telescoping fiberglass mast  (affiliate link) or an inexpensive Goture Red Fox Super Hard 720 carbon-fiber fishing pole (available from multiple sellers on Amazon) from which I’ve removed the top three sections to create a sturdy 18’ pole that collapses to less that 30″. (If you order a Goture 720, be sure to order the “7.2m” version because the top three sections are far too whippy to support a wire.)

I’ve supported the 31’ Jackite mast using a drive-on base (more on this below), bungied to a fence-post or sign-post found on-site, and bungied to my folding camp-chair.

I’ve supported the Goture Red Fox 720 on a custom stake (more on this below) and bungied to my bicycle.

Goture Red Fox 720 bungied to a bicycle and supporting a wire antenna
The Goture Red Fox 720 mast bungied to my bicycle and supporting a wire antenna as a sloper; the KH1 station is on the picnic table.

 

a loop bungie
The sort of bungie I use to strap a mast to a post, my bicycle, or a folding chair.

I often support my 31’ Jackite mast using a homemade drive-on base. This base is constructed from a scrap of 2”x10” pine about 23” long,  a 4″ black plastic toilet flange, a 2’ length of white PVC chosen to provide a friction-fit in the toilet flange, and a PVC reducer at the top. The photos below should provide enough information for you to build your own. I don’t glue any of the plastic items together; I rely on friction to hold the pieces together and I slip the 2’ pipe out of the toilet flange for easier transport in my car. (Disclaimer: I drive a small Honda Fit; I don’t know how well a 2”x10” pine board would survive repeated abuse by a large SUV or pick-up truck.)

Components of the drive-on mast support
The components of the drive-on mast support: a piece of wood, a toilet flange, and some PVC.
drive-on mast base assembled
The drive-on mast base, assembled.
drive-on mast base in use
The drive-on mast base in use at Burr Oak State Park. The 31′ Jackite mast is supporting the 28½’ EFRW as a vertical and three 17′ counterpoise wires extend out from the bottom of the front passenger door. The station is inside the car.

 

 

 

The spike for the Goture Red Fox 720 is simply a 7” length of white PCV just big enough to slip the large end of the mast into, with a matching PVC cap on one end drilled to accept a 3/8” diameter, 8” long spike. Originally, I tried using epoxy to secure the spike in the cap, but this failed, and now I’m using an appropriately-sized push-nut to hold the spike in place. (The PVC and the 8” spike were found at the local big-box store; the push-nut was found at a local well-equipped hardware store.)

Goture Red Fox 720 and custom spike
The Goture Red Fox 720 and the custom spike.
close-up view of the push-on nut securing the metal spike
A close-up view of the push-on nut securing the metal spike to the PVC cap.

 

I hope this article gives you some ideas for your own field operations!

73,
Eric McFadden, WD8RIF
https://wd8rif.com/radio.htm


A huge thanks to Eric (WD8RIF) for taking the time to document his antenna setup in such detail! His approach demonstrates that you don’t have to spend a fortune to get on the air with an effective self-supporting antenna system.

Personally, I believe that using an arborist throw line, a tree, and a simple wire antenna is often the most affordable and effective way to get on the air. However, depending on where you live or where you activate, trees may not always be an option. That’s why having a self-supporting antenna system in your toolkit is always a good idea—it gives you the flexibility to operate anywhere.

If you’ve built an affordable self-supporting antenna system that works well for your field operations, I’d love to hear about it! Feel free to share your experiences, designs, or recommendations in the comments or in a guest post. The more we exchange ideas, the more we can help fellow operators—especially those just getting started—find practical, budget-friendly solutions for getting on the air.

Field Radio Kit Gallery: N5YCO’s Lightweight CFT1 SOTA Kit

Many thanks to Corey (N5YCO), for sharing the following article about his portable field radio kit, which will be featured on our Field Kit Gallery page. If you would like to share your field kit with the QRPer community, read this post.


CFT1 Field Kit

by Corey McDonald (N5YCO)

I thought I would supply the field kit that I use for my CFT1. I prefer SOTA activations when I can, so my kit is on the lightweight minimal side.

All of the 3d printed parts are carbon fiber PETG for strength.

Not pictured: Small log notebook, SOTABeams Carbon6, guy ring and lines.

My kit consists of the following:

Note: All Amazon links are affiliate/partner links that support QRPer.com at no cost to you.

72,

– Corey N5YCO

Snow, Sand, and Solar Storms: Tim’s New Year’s Eve Radio Adventure

New Year’s Eve Sand Dune SOTA & POTA

by Tim (W8TMI)

My wife and I head to Northern Michigan over the New Year’s holiday almost every year. It’s a nice way to wrap up the year and the busy holiday season. Most of our friends and family obligations are met, and we can spend time unwinding and exploring the wonderful things that Michigan has to offer.

This year was no exception. We found a nice place to stay in Frankfort, Michigan. Several breweries, eateries, coffee houses, hiking trails, miles of shoreline, and a local bookstore made this an ideal location for a few days with nothing pressing to accomplish.

Being a ham, I always take a peek around to see what POTA and SOTA entities may be nearby wherever we end up staying. I was in luck, there was a SOTA within a POTA just north of where we were staying. Along the Sleeping Bear Dunes National Lakeshore (US-0767) is Empire Bluffs sand dunes (W8M/LP-019). This was too much to resist.

Sleeping Bear Dune National Lakeshore

As the plans firmed up around our timeline and bookings, my mind began to imagine the activation. I am well versed in POTA activations and have many tricks to overcome beaches, snow, lack of picnic tables, lack of trees, and many other things that can come my way. My mind began to question if I had the right gear to make this happen and I began to plan for a setup that could be deployed and operated in harsh conditions with little assistance from the environment around me.

I have learned from my previous experiences on the sand dunes of the Great Lakes that  conditions can be challenging. I knew I would more than likely face snow on the ground, new snow in the air, wind, cold temps, sand, narrow dune peaks, local vegetation, and the challenge to hike all of my gear to the spot. Now it was time to take what I had and turn it into the SOTA/POTA setup that could get the job done.

The antenna would be the GabilGRA-7350  [QRPer.com affiliate link] with three 13’ radials deployed out as far as I could get them. Gabil recommends setting the antenna to the general resonance area marked on the coil and using a wide range tuner to finish the job. I have found this to be true, especially analyzing the antenna on the soil in my backyard where I can get a 1:1 SWR match versus the sandy beaches of Lake Michigan.

Gabil GRA-7350, spare whip, and three 13′ counterpoises attached via 2mm banana plugs

I chose the CFT1 as my radio. It covers the bands that I would more than likely operate and with the Tufteln face cover it weighs around 8 oz.

20 meters being the primary band because with the wind and cold, I knew speed would be paramount. For the tuner and battery, I chose the mAT-10 ATU and the Talentcell 3000 mA Li-Ion [QRPer.com affiliate link]. Finally, the N0SA M7 iambic paddle.

CFT1, mAT-10 tuner, Talentcell battery, N0SA M7, Rite in the Rain book and pencil

To bring this kit together in a way that I could operate standing up, I needed some kind of bag or pouch to wear that would allow access to the tune button on the tuner, the volume and VFO on the radio, ability to log, and key without having to hold on to the paddle. As a fly fisherman I thought about a sling pack or a chest pack, but neither would work with any of my backpacks I planned to haul the antenna.

My friend Erik (WS3D) recommended a waist pack. At first glance I wasn’t sure this could meet my needs. Off to the local shopping center I went to see if I could find some options that could accommodate my SOTA kit. After going into five different stores that had some forms of waist packs, my local athletics sporting goods store had one that I thought might work with some minor modifications.

It was small, which meant it could easily fit into the backpack I planned to use. Once I got home, I was able to stuff each component into one of the several pockets provided on the pack. The question remained: how do I key without holding the paddle?

Following the tip provided by N0SA who designed and made the M7, Velcro attached to the bottom of the key would allow adhesion to the pack. I was able to purchase some of the “loop” material from JoAnn and got to work with my sewing machine. A small 2”x3” portion on the right side of the pack would allow for right hand keying while I kept the logger in my left hand. Keeping my right hand free to operate the message functions, volume, and VFO of the radio if needed.

Outdoor Gear fanny pack with sewn on hook and loop patch

I had a kit and a plan, now to get to it. Continue reading Snow, Sand, and Solar Storms: Tim’s New Year’s Eve Radio Adventure

Field Radio Kit Gallery: Pedro’s (tr)uSDX Field Kit

Many thanks to Pedro (PP2PB), who shares the following article about his portable field radio kit, which will be featured on our Field Kit Gallery page.


Pedro’s (tr)uSDX Compact and Affordable Field Kit

by Pedro (PP2PB)

Here’s my new kit.

This kit weighs just under 1,2kg and has phone and CW operations in mind. I might add some cables for digital modes, but I haven’t tested this rig with digital modes, just yet.

The (tr)uSDX was bought assembled with the LO bands RF board, and I assembled the HI RF board myself. I got Adam’s alternative case printed out for easy band switching and did a minor mod to the RF boards soldering a Zener diode reverse polarized as a high SWR protection.

I also added a USB port to the battery pack because the (tr)uSDX can operate with around 0,5W directly from USB and that’s a great way to test for SWR and fine tune the antenna without stressing the finals.

The manual antenna coupler is also my creation and even though it doesn’t appear on the exploded view it does fit in there no problem (it was added after I took the pictures).

Gear List:

72 DE PP2PB

Field Radio Kit Gallery: KM4CFT’s CFT1 Field Kit

Many thanks to Jonathan (KM4CFT), for sharing the following article about his portable field radio kit, which will be featured on our Field Kit Gallery page. If you would like to share your field kit with the QRPer community, read this post


CFT1 Field Kit

by Jonathan (KM4CFT)

I thought I would supply my own field kit I recently put together for my CFT1.

This will also be the official announcement of my newest product, which is a CW Key leg strap. The leg strap is something I originally got my dad to fabricate for me out of some scrap metal a while back, and now that I have the version 2 iambic paddles, I thought it would be nice to mass-produce them. They are compatible with any magnetically mounted paddle.

This is my CFT1 Go Bag. It contains everything I need to activate my CFT1 except for a mast or throwline.

The kit consists of the following:

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72,
-Jonathan KM4CFT