Tag Archives: Portable Radio

Dennis reminds us how much times have changed for portable ops

Many thanks to Dennis (WQ7O) who shares the following article:

POTA – Getting There

by Dennis (WQ7O)

POTA activity seems to be popular and growing. I have been a ham since the 60s and I am excited by how fun POTA hunting and activating this “new” radio sport can be. I have heard it called “Field Day” every day.

Drawing on decades of hamming experience, I contemplated how we got here. I remember my first field day and the effort required. Basically, equipment meant to be used in an indoor and fixed environment was adapted for portable use. Let’s take a look at what that might mean.

Power supplies that operated on DC were available but expensive. Looking at say, a Drake

TR-4, a popular transceiver at the time, the rig cost $700 in 1968 dollars. The power supply and speaker ran another $200 or so. You’ll need a mic and key, which were not included. Few tuners were available. You could go for a Johnson Matchbox. Drake made the MN-4 and

MN-2000 to match your TR-4. Count on another $200 or so. If you are a CW op and you want a keyer, the Hallicrafters TO keyer and a Vibroplex paddle were another $200. The gear described here would just fit on an office sized desk and don’t ask about the weight.

Now just gather that up and take it to the park, right? Well for starters the DC supply was for mobile use not portable use. You won’t operate for long off a battery with the amperage needed to warm all those tubes. So, bring along a generator and that’s what we did. BTW, we used a truck to transport it all because we needed it. Backpacks weren’t useful.

Antennas were all for fixed use as well. We brought a tri-band yagi and lashed it on a mast to the truck. We ran some wire antennas and we were on the air. Antenna analyzers simply did not exist, we tuned around and graphed it by hand.

Image Source: RigReference.com

This may sound much like a modern field day but hardly the “light and fast” deployment of a SOTA/POTA activation. Also, take it from me, running tube gear in the field is tough. I had a Gonset Communicator (2 meters) issued to me by our ARES group. It was about 100 times the displacement of your trusty handheld and many times the weight.

So since the 60s, the microprocessor, large scale integration and SDR technology have reduced the size and power requirements for all the gear we use. Today a radio that fits in a pocket can include a rechargeable power source, an antenna tuner and run from 160 meters through UHF offering all modes.

From lead acid, NiCads, NiMH, Lithium Ion and now LiPO batteries, the availability of reliable and portable power sources to power rigs and accessories is a fairly recent development. The increased efficiency coupled with decreased power demand have set us free. How many of us have quick deployment solar panels to keep those batteries topped off during extended operation? It beats the noise, smell and mess of gas cans and a generator. Also, you do not want to backpack a lead acid battery for a SOTA activation. Too much weight and not enough power.

Then there is the internet. If you do POTA like I do POTA, you go to the web page and look for spots. How many would you find without the spots and the RBN? When an activation is deployed one of the first actions is to spot it on the POTA app. Thus, as with other digital modes, the internet becomes an integral part. We could do POTA without the internet, but it would be a whole lot harder. And our taken for granted cell phone brings the internet right to the picnic table.

Image Source: Universal Radio

What about the gear? What should we use and how available is it? Early rigs for portable and QRP use were not plentiful or feature rich. The styling of the popular Penntek TR-45 is reminiscent of the Heathkit “Benton Harbor Lunchbox.” At the risk of understatement, the features do not compare.

The manufacturers responded. We weren’t all going to home brew our QRP rigs. So came the Yaesu FT-817. In 2001, Yaesu introduced the 817 which did all modes, 160 through UHF, ran on batteries, fit in your backpack and was affordably priced. Suddenly, portable operation was possible, versatile, affordable, reliable, practical and fun. We were freed from attics, basements and garages and embraced nature.

I recently built a QRPLabs QCX mini. This tiny rig has more features than we ever knew we needed when we were operating that Drake TR-4. If you want more bands the LNR Mountain Toppers are wildly popular. Other manufacturers, large and small, increased the offerings with different form factors and features.

This included antennas. An early entry was the Buddipole. Many cottage industry entrepreneurs followed and today the selection of quick and easy deployment antennas is broad and deep. From a whip antenna to attach to the rig itself to wire antennas for 160, there are a lot from which to choose. Don’t forget that 3D printing also accounts for a lot of our accessories like keys, cages, stands and winders.

Want to add a tuner to your station? The Elecraft T1, I built mine as a kit, is a superb, self contained tuner and offers broad, automatic matching running on a 9 volt battery. Since the T-1, LDG, MAT MFJ, Icom and others have offered great tuner choices that travel easily as part of your kit.

Anyone who owns a Baofeng knows that the Chinese have entered the ham radio market. While the quality and availability of these rigs can be an issue, they are quite affordable. This brings in new users who learn the hobby and progress to greater things. I have heard hams criticize the quality of MFJ products. MFJ makes the accessories the major manufacturers don’t and at popular prices. When there are more licensed operators, the manufacturers can offer more products at better prices as markets expand. Xiegu HF radios have powered many activations with its built-in battery, tuner and microphone. If POTA and QRP were not driving activity would Icom have brought out the IC-705? The Elecraft KX-2 and 3, the Lab 599 TX-500 and these types of boutique radios answer market demands.

The “Prepper” movement evolved from natural disaster “EmComm” and operating “off the grid” has increased the demand and thus the supply of gear. Building a portable kit has gotten easier and more affordable with a broad selection of choices and options. More is better.

Lots of other simple things have come together to bring us to the “10 minute setup” of the QRP SOTA/POTA activation of today. A whole room full of heavy, power hungry gear has been reduced to a device that literally fits in a pocket. Add a wire and you are on the air. My ham career began as a boy with a tube driven Heathkit transmitter with crystal control fixed frequency in the attic of our family home. I don’t think anybody appreciates more than me opening a backpack and in a few minutes setting up a modern station, wherever I am. QSOs around the country and around the world roll in with a few watts and a wire.

CQ POTA…73 de WQ7O

Rich’s easy-to-build and incredibly affordable Field Clip Board V 1.0

Many thanks to Rich (KQ9L) who writes:

Hello Thomas,

I’ve attached couple pictures of V1.0 of my field clip board. I’ve been searching for the perfect clipboard to use in the field. The main requirements of the design include: lightweight, low cost and the flexibility to allow a comfortable operating position while securely holding a radio.

What I came up with is a based on an inexpensive fiber board clip board:

I chose to set it up somewhat unconventionally and designed it to use the clipboard “upside down”.  Setting it up this way provided ample space at the top to mount the radio while still providing room to attach a metal pad mounting point for paddles.

The radio is held securely in place with craft 3mm elastic bands. The bands were made with metal “toggles” so I can easily add more holes to the clipboard to accommodate varying rigs.

The metal pad is just a stick-on metal plate purchased from Amazon. I plan to add a leg strap in the future and will do so once I’m sure no other major modifications need to me made.

I’m pretty happy with the way the clipboard came out and would appreciate any comments or suggestions!


This is brilliant, Rich! I love both how affordable this board is and how easy it is to build. Having the clip at the bottom of the board is a fantastic way to secure your logging notebook as well. 

Thank you for sharing!

Paul’s potentially explosive portable ops in St. Elmo, Colorado

Many thanks to Paul (W0RW) who shares the following guest post:

Operating in St. Elmo Ghost Town, Colorado

by Paul (W0RW)

I have operated in St Elmo (Ghost Town) several times with my PRC319 Pedestrian Mobile.  St. Elmo is at 11,000 feet in a deep canyon so it was hard to make contacts.

My PRC319 runs 50 Watts and I use a 10 foot whip so I had some success to the East on CW. I use a Whiterook MK-33 for a hand held single lever paddle.


Right after my last visit,  July 2015, members of St. Elmo and Chalk Creek Canyon Historical group  cleaned out the outhouse behind the Home Comfort Hotel in St. Elmo, they found a potentially explosive surprise. On the floor of the outhouse, they found what they believed to be dynamite. Later in the day the bomb squad found blasting caps rather than dynamite.

St Elmo Outhouse

[Per the Historical Society] there were only 6 Blasting Caps found at St Elmo’s. They called Ft. Carson US Army EOD and they blew them up right there in the center of town.

While the electric blasting caps are usually shorted and would not be effected by a QRP radio, my 50W radio was  at a dangerously high level to be transmitting near a box of blasting caps.

It would be a smart idea to avoid operating in any old mining areas where unexploded dynamite might exist.

Paul    W0RW

St Elmo, Colorado

Scott’s Elecraft KX3 Go-Box

[Note: this article was originally posted on my shortwave radio blog, The SWLing Post.]

Many thanks to Scott (AK5SD) who shares the following photos and bill of materials for his custom Elecraft KX3 go-box:

IMG_0531 IMG_0534

IMG_0532 IMG_0535 IMG_0537 IMG_0536

Bill of materials

The panel was custom laser cut by Front Panel Express. I have the CAD
file and I’m willing to share it with anyone who wants to reproduce my effort.

Case B&W Type 1000 Outdoor Case with SI Foam
You won’t use the foam, so you can buy the version without it if you can find it cheaper.

Battery Anker Astro Pro2 20000mAh Multi-Voltage (5V 12V 16V 19V)
Portable Charger External Battery Power Bank
Avoid look alike batteries and the next generation model from Anker. The newer Anker
battery is only capable of delivering 1.5A from the 12V supply. Two look alike batteries
I tried did not have the auto-off feature that the Anker does.

ACC2 and I/Q Jacks 2 x 2.5mm Stereo Jack Panel Mount (PH-666J-B)
Phone, Key, and ACC1 3 x 3.5mm Stereo Jack Panel Mount (High Quality) (PH-504KB)
Mic Jack 1 x 3.5mm 4 Conductor Jack Panel Mount (PH-70-088B)
12V IN and CHG IN 2 x 2.1mm DC Power Panel Mount Jack (PH-2112)
12V OUT 1 x 2.5mm DC Power Panel Mount Jack (PH-2512)

You also need plugs and wire for interconnects. I bought some 2.5mm (CES-11-5502)
and 3.5mm (PH-44-468 for stereo, PH-44-470 for 4-conductor) audio cables with right
angle plugs and just cut them to use for the signal lines going to the KX3. I did the same
thing for the 2.5mm (PH-TC250) and 2.1mm (PH-TC210) power cables. A couple of
caveats are in order. The Phone, Key, and ACC1 interconnects require low profile
right angle connectors. The cables I listed above won’t work. Vetco part number
VUPN10338 will work. The power cables I’ve listed above use 24 gauge wire. This
is a little light, but the runs are small so I think it is OK. You can use higher gauge
cables if you can find a source.

USB OUT USB 2.0 Right Angle Extension Cable (RR-AAR04P-20G)

L Brackets 8 x Bracket Rt Ang Mount 4-40 Steel (612K-ND)
These L brackets are used to mount the KX3 to the panel and the panel to the case.
For mounting the KX3, I use a little piece of stick on felt on the bracket to protect the
KX3’s cabinet from damage. Replace the KX3’s screws with #4-40 Thread Size, 1/4”
Length Steel Pan Head Machine Screw, Black Oxide Finish (see below). For the panel
mounting, use #6-32 Thread Size, 3/16” Length self tapping sheet metal screw. You
may need to cut the tip off in order to not puncture the outside of the case.

RG316 BNC Male Angle to BNC Female SM Bulkhead Coaxial RF Pigtail Cable (6”)
This is not the original interconnect I used for connecting the KX3’s antenna output to
the panel. However, I think it is a better option for new designs. The caveat is that you
will need to verify the hole in the panel matches the bulkhead connector on this cable.
There will be a little loop in the cable when you are done, but that is fine.

Screws for Sound Card 2 x FMSP2510 – M 2.5 x .45 x 10mm
Screws for KX3 Bracket Mount 4 x MSPPK0404 – 4-40 x 1/4
Screws for Countersunk Panel Holes 8 x FMPPK0403 – 4-40 x 3/16
Screws for USB Connector *** 2 x FMPPK0406 – 4-40 x 3/8

I’m pretty sure these are the right length for the USB connector. I am doing it from memory.

Amazon.com or eBay.com
Soundmatters foxL DASH A Wireless Bluetooth Soundbar (OPTIONAL)

Sonoma Wire Works GJ2USB GuitarJack 2 USB Portable Audio Interface (OPTIONAL)
(Make sure you get the USB model, not the 30-pin model.)

This is optional if you want a built-in sound card interface for a waterfall display using iSDR. Make sure to eliminate the holes in the upper left corner of the panel if you are not installing. You will also need 2.5mm x 10mm screws to mount this to the bottom of the panel (see below).

bhi Compact In-Line Noise Eliminating Module (OPTIONAL)

In my opinion, the KX3’s noise reduction is totally ineffective for SSB communications. This external noise reducing DSP is one solution, albeit an expensive one, to that problem. It is only for SSB, not CW or digital modes. It is also available from GAP Antenna Products.


Scott: you have done a beautiful job here and have spared no expense to make a wonderfully-engineered and rugged go-box. No doubt, you’re ready to take your KX3 to the field and enjoy world-class performance on a moment’s notice. 

Though I’ve never used them personally, I’ve noticed others who have taken advantage of the Front Panel Express engraving service–certainly makes for a polished and professional front panel.

Again, many thanks for not only sharing your photos, but also your bill of materials which will make it much easier for others to draw inspiration from your design!


Speaking of designs, when I looked up Scott on QRZ.com, I noticed that he also sports a QSL card (above) designed by my good friend, Jeff Murray (K1NSS). Obviously, Scott is a man with good taste!