All posts by Thomas Witherspoon

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

POTA Plan C: Swapping antennas and rigs at Tuttle Educational State Forest

9 Comments

After the success of my previous day’s activation at Fort Dobbs State Historic Site, I decided to take the Icom IC-703 Plus out for yet another activation.

As I mentioned in the previous post, the IC-703 has not gotten a lot of outdoor time this year because I’ve had issues with the electronic keyer locking up when using the radio with end-fed antennas.

Of course, there are a number of ways to mitigate or radiate the RF that could be coming back to the radio, so at Fort Dobbs, the previous day, I used a simple common mode choke. It seemed to do the trick.

I was curious if using a common mode choke might be the only solution needed to solve this problem, or if I’d need to perform a mod to my IC-703.

I was ready to test the IC-703 again.

I had a fair amount of antenna options in the trunk of my car, so on the way to Tuttle Educational State Forest (on Friday, October 7, 2022), I considered a few options to shake things up a bit.

Since I was feeling comfortable that the common mode choke was taking care of things, I decided to push the limit a bit and deploy an end-fed random wire antenna. I didn’t have any of my mini portable 9:1 random wire antennas in the car (PackTenna, Tufteln, etc.), but I did have another solution: the Chameleon MPAS Lite.

The cool thing about the CHA MPAS Lite is that while it’s primarily designed to be a vertical antenna with counterpoise, it can be reconfigured and deployed a number of ways including as a simple end-fed random wire antenna.

After giving it some thought, I decided it might be fun to deploy it as an inverted V random wire. In fact, here’s a diagram from the MPAS Lite manual of exactly what I planned to do.

I’d be using the MPAS Lite counterpoise as the radiator, so I wouldn’t have the optional second counterpoise as seen in the illustration above. That’s okay, though, because I was feeding the antenna with Chameleon’s 50′ RG-58C/U cable with in-line choke; the shield of the coax would act as the antenna counterpoise.

This is the same coax cable I used the previous day. Continue reading POTA Plan C: Swapping antennas and rigs at Tuttle Educational State Forest →

Accessories, FT8, How To, News, QRP

How Joe keeps his Icom IC-705 cool during long FT8 sessions

6 Comments

Many thanks to Joe (KD2QBK) who writes:

Hi Thomas:

I’ve recently discovered QRP FT8, which I’ve been working with my Icom IC-705. I run with an end-fed sloper that runs out of my 2nd floor shack window using a 49:1 unun and a length of RG-58. I’m also using an Emtech ZM-2 tuner between the antenna and the radio when needed.

The set up works really nicely, except for the way FT8 heats up and overtaxes the radio after a while. Searching around a bit, I’ve found just the right solution for that issue. The AC Infinity MULTIFAN S1 USB-powered table fan.

https://amzn.to/3DvqemJ (affiliate link)

It’s basically just a 3-inch square fan like you’d find in a computer or some other electronic devices, with rubber “feet” attached. It can stand upright or lay flat depending on your need. it’s stated purpose is to cool or ventilate routers, game consoles, audio equipment, etc.

The AC Infinity MULTIFAN S1 includes a speed control switch and an inline USB socket to daisy-chain other devices. One caveat with the inline socket: because it’s placed in the line between the fan and the speed control switch, the switch must be set to high speed else the socket won’t have adequate power for the attached device.

All I do is plug the fan into a USB socket and place it at the rear of the radio, sans battery, to keep it cool. I have it set up to blow onto the radio. Obviously I need to power the radio with an external source when the battery isn’t attached. I’ve not tried to use the fan with the battery attached, but I don’t think it would help much. The ventilation slots next to the battery compartment don’t seem wide enough to let much air in. Continue reading How Joe keeps his Icom IC-705 cool during long FT8 sessions →

Field Reports, Guest Posts, News, Portable, POTA, QRP

Rich’s Triple Activation Day!

4 Comments

Many thanks to Rich (KQ9L) for sharing the following field report:

Triple Activation Day

by Rich (KQ9L)

I decided to build on the momentum and lessons learned from my last two POTA outings and yesterday [October 29, 2022] completed x3 Activations in one day— a first for me. I wrote a brief description of the day and I hope you enjoy reading about the activations.

Well the weather has been pretty good here in Chicago and Old Man Winter hasn’t made it around to these parts yet and being on a POTA kick lately, I decided see if I could complete several activations in one day. Previously I had completed x2 in one day, but felt that after all that I learned from my last couple activations, I should practice what I learned and go for three.

In my area, there are several POTA sites, but one area to the south of me seemed to be the best location to accomplish my goal. The area has a unique geographic feature and historically interesting landmark which added to the lure of the area. The region centers around the Illinois and Michigan Canal.

Here is a quick history lesson courtesy of Wikipedia:

The Illinois and Michigan canal was build in 1848 and served as a connection between the Great Lakes and the Mississippi River. Running 96 miles, it connects Bridgeport in Chicago to LaSalle-Peru. Why was this important? This connect helped establish Chicago as the transportation hub of the US and linked by water the East coast to the Mississippi River and from there the Gulf of Mexico. Before the railroad era in the US, this water way dominated transportation.

Pretty cool!

Along the canal are numerous little hamlets and one in particular, Morris, Illinois had x3 State Parks all within about a 5 mile radius. Perfect!

First stop was Gebhard Woods State Part (K-0995). The park is only 30 acres, but affords activities for hikers, fisherman, campers and picnickers. There is even an eBike rental facility so the park has broad appeal to many people, including hams!

I arrived pretty much right after sunrise and was greeted by fog and a thin layer of frost on the grass and picnic tables. Though beautiful this frost and fog, did not make for a fun activation. Temps were in the upper 30’s F, but with the fog the air felt damp and overall much cooler.

I hurriedly set up my PackTenna 9:1 antenna on my collapsible mast and leaned it up against a nearby tree. I had a separate counterpoise and feed line with a choke built into it…more on this later.

Continue reading Rich’s Triple Activation Day! →

Guest Posts, News, QRO, QRP

Guest Post: “Why I Quit QRP (and maybe shouldn’t have)”

16 Comments

Many thanks to John (VA3KOT) who shares the following guest post which was originally published on his Ham Radio Outside the Box blog:

Why I Quit QRP (and maybe shouldn’t have)

by John (VA3KOT)

For many years I was a dedicated QRP operator. I even took my “Portable QRP Operation” show-and-tell out on the road for presentation at ham clubs in my area. Then along came the dark, gloomy depths of the solar cycle minimum. My forays out into the Big Blue Sky Shack became a series of disappointments. Maybe the odd QSO here and there, but most often I came home with nothing but a few RBN spots after multiple CQ calls. Something had to change.

“Why QRP?“

I began to ask myself “why QRP?”. It’s a valid enough question. Just what is so magical about an output power of 5 watts? Why not 1 watt, 3 watts, or 20 watts? It has often been said that 5 watts of CW is equivalent to 100 watts of SSB. There is a mathematical proof but I won’t repeat it here. So shouldn’t 100 watts of SSB be considered QRP?

QRP has a cult-like following. There are several online organizations dedicated to it. I am a member of some of them. QRP certainly has an appeal for those of us who like to operate in the great outdoors. Perhaps the greatest advantage is that an entire station can be stuffed into a couple of pockets – antenna and all. And a QRP rig sips battery power so slowly that some can be powered all day on a 9-volt alkaline battery.

I laid the blame for my lack of portable QRP QSOs on poor propagation. Maybe my signal just wasn’t making the trip. The propagation demons in the sky were swallowing my signals, burping and grinning down at me with a smug, malicious gleam in their eyes. QRP-’til-I-die operators shrug that off as “the fun of QRP”. Not getting any QSOs is fun?

In hindsight, there could have been another explanation. The Reverse Beacon Network was constantly reaffirming that my puny emissions were making it up to the ionosphere and being refracted back down to the Earth. So why were so very few people responding to my CQs? I have a theory about that. Maybe, back then, random CQs only appealed to a small number of people. I asked myself how often I responded to random CQs. Hmmm, not too often!

Anyway, images of QRO rigs were dancing around my head whispering sweet messages of temptation in my ear. “Yes” I said to myself; “that’s the answer. Maybe I just need to blow more watts into the air and I will fill up my logbook!” But first a roadblock. I had to persuade “senior management” that I should invest in a new radio. Continue reading Guest Post: “Why I Quit QRP (and maybe shouldn’t have)” →

News, QRP Radios

Evidently loads of love for the Icom IC-703!

9 Comments

It’s funny: without fail, when I post a new field report or activation video, I get comments from readers about the radio I used during the activation.

“I love that radio…”

“I can’t stand that radio…”

“Why did I ever sell that radio…?” 

If you you follow QRPer.com or my YouTube channel, you’ve likely seen these too.

We’re passionate about our radios for good reason: they’re the hands-on bit…our main interface with our wireless world.

IC-703 Love

Something that has really surprised me are the number of comments I’ve seen from readers and subscribers praising the IC-703.

Since I posted my last activation video, I’ve gotten so many notes on QRPer, YouTube, and via email from those of you who simply love the IC-703.

At least seven of you have told me you still have the original IC-703/+ you purchased new and that you’ll never let go of it.

Impressive!

I love hearing comments like this. The ‘703 is a cool radio in so many respects.

My IC-703 Plus has been a little temperamental and I need to do the Icom-suggested modification that sorts out keyer lock ups. As you’ll see in my next field report, mine does still have issues using end-fed antennas even when using an in-line common mode choke. I could, of course, attach counterpoises to my end-fed antennas and likely mitigate this, but I’d like the ‘703 to be robust enough to handle antennas in my kit just like my other field radios.

I’m convinced the modification will work based on what I’ve read.

Again: great to see all of the ‘703 love! Thanks for that!

Hacks and Hints, News, Portable

How Paul logs while operating pedestrian mobile

2 Comments

Many thanks to Paul (W0RW) who writes with the following tip:

It is a little cumbersome to log your contacts while walking along the trail. For logging and a Dupe Sheet (used in contests) i use a small NFL Type Cuff Log.

You have seen all the Quarterbacks have their ‘Play List’ on their arm. They are on eBay at:

https://ebay.us/E6MK0u

The NFL Play Lists (Cuff Logs) that are on eBay are
‘Read Only’, mine is a ‘Read/Write’.

You have to make your own to be able to write on it.

Mine is a little 3 x 5 card on a metal plate with 2 elastic bands that strap to my left arm.

The metal plate gives me a good writing surface.

There is also a little goose neck LED light that is clamped to the top for Night Ops.

The muff log winterized option!

Paul w0rw

Thanks for sharing this, Paul!

Morse Code, News, Product Announcements, QRP, QRPer Notes, Videos

QRPer Notes: IC-705 Firmware Update, New YouTube Channels, and ARRL Handbook 100th Edition

3 Comments

Because I receive so many tips from readers here on QRPer, I wanted way to share them in a concise newsletter format.  To that end, welcome to QRPer Notes, a collection of links to interesting stories and tips making waves in the world of radio!

IC-705 Firmware Update

Many thanks to Uli Zehndbauer who notes that Icom recently released a new firmware update for the IC-705.

Here are the details/notes about this firmware version from Icom:

Changes from Version 1.27

      • – Displays the Receiving (or Transmitting) route icon (RF or TM: Terminal mode) on the RX History Log and QSO Log
      • – Displays the Receiving (or Transmitting) route icon (RF or TM: Terminal mode) to the chunk information in the QSO audio file
      • – Displays the Receiving route icon (TM: Terminal mode) to the following screens;
        • RX HISTORY screen
        • GPS POSITION (RX) screen
        • QSO audio, PLAY FILES screen
        • QSO audio, FILE INFORMATION screen
      • – Improves the WLAN access point list so that you can delete the connected or saved access points
      • – Improves the CI-V command 1F 01 (DV transmit call sign) so you can set only the “UR” call sign without the other call signs.

Click here to download the firmware from the Icom website.

New CW YouTube Channels/Videos

In the past two weeks I’ve received a number of video links from QRPer readers who are featuring CW activations in their YouTube videos.

First up is Steve (K9NUD) who has started a new channel featuring his CW activations primarily using a cootie/sideswiper. Steve is doing something I wish I had the time to do which is add CW closed captions to his videos. This makes it easy to follow along. Check out this video:

Jonathan (KM4CFT) recently noted in the comments of my YouTube channel that he made a video of his third ever CW POTA activation. I had to check it out and am glad I did. You get a very good idea of what it’s like on the air as a CW newbie. In other words: not that bad at all! Incidentally, when I looked up Jonathan on QRZ, I discovered we have a mutual friend in Zach (KM4BLG).

Keep up the great work, Jonathan!

Chris (KD2YDN) sent me a link to the following video on his new YouTube channel. In the video I actually get to hear what my signal sounded like during his SOTA/POTA activation. He certainly captured some amazing morning scenery and a gorgeous sunrise from Westkill Mountain:

I think you should consider checking out these videos and subscribing!

The ARRL Handbook 100th Edition

The ARRL has announced pre-orders for their new ARRL Handbook. I feel like everyone should have a copy of the Handbook. It’s simply chock-full of useful information–much of which is simply timeless. I still reference the 1994 handbook my buddy Mike (K8RAT) gave me shortly after I got my license in 1997. I feel like it’s important to have reference material like this in paper.

As a side note, I’ve been to a number of shortwave radio broadcast transmitting stations and at each one of them I’ve seen the ARRL Handbook on the Chief Engineer’s shelf. Lots of great radio principles inside.

The book is $80 on pre-order. That’s a lot for a book, but it’s also a LOT of book!

Here’s the announcement from the ARRL:

We have arrived at a milestone. The 100th edition of The ARRL Handbook for Radio Communications is here: Handbook 100. How do you celebrate the most widely used one-stop reference and guide to radio technology principles and practices? By continuing to fill the pages of another edition with the progress and achievement of radio amateurs. Handbook 100 is written for everyone with a desire to advance the pursuit of wireless technology. Here is your guide to radio experimentation, discovery, and innovation.

What’s Inside

Each chapter is filled with the most up-to-date knowledge representative of the wide and ever-expanding range of interests among radio amateurs. There are practical, hands-on projects for all skill levels — from simple accessories and small power supplies to legal-limit amplifiers and high-gain antennas.

Key topics:

    • Radio electronics theory and principles
    • Circuit design and equipment
    • Signal transmission and propagation
    • Digital modulation and protocols
    • Antennas and transmission lines
    • Construction practices

Updated with new projects and content, including:

    • An all-new chapter on radio propagation covering a wide range of bands and modes
    • New and updated sections on electronic circuit simulation
    • New cavity filter and high-power HF filter projects
    • New coverage on digital protocols and modes
    • New material on RFI from low-voltage lighting and other sources
    • Revised sections covering new RF exposure limits
    • New content on portable station equipment, antennas, power, and assembly
    • New material on ferrite uses and types
    • New section on how to use portable SDR to locate sources of RFI …and more.

Click here for more information and to place an order.

Guest Posts, How To, Radio Field Craft

Radio Field Craft: Rand explores the handy Prusik Knot

11 Comments

Many thanks to Rand (W7UDT) who shares the following guest post:

The Prusik Knot… strain relief for Wire Antennas and Coax.

By W7UDT, Randall ‘Rand’ Tom

The Prusik knot is a simple, yet effective means to provide needed strain relief to wire antennas and coax, while deployed. It’s comprised of a simple loop or length of suitable cordage (of smaller diameter than the shank, Coax or Wire, it secures).

The link below, is from our friends at Animated Knots…. It’s a brief video tutorial on how best to tie the Prusik knot. Having the Prusik in your ‘bag of tricks,’ will help make your next field deployment be a successful one.

https://www.animatedknots.com/Prusik-knot

As seen in the instructional video, the knot is comprised of a simple loop of cordage, sufficient in length for the task, which is fine, but, I would recommend NOT making a loop. Rather, keeping tag ends for easier anchoring. These tag ends should be at least 12” in length. This is called an open-ended Prusik. Either way, both have utility.

To do this, fold a 24” of cordage in half, to make a ‘bite.’ Lay the bite over the shank of the coax or wire, and feed the tag ends inside the bite loop. This forms a larks-head knot. Wrap two additional turns around and through, then dress and test the knot to form the Prusik. Simple. Anchor (tie) the tag ends at a point where strain relief is best positioned. Then adjust (slide) it to load.

After deployment, I would also recommend leaving the Prusik attached. It comes in handy, when coiling your feed lines or elements later for proper storage.

The Prusik allows it to slide along the wire or coax while free of tension, yet it holds fast under load. Much like a monkey’s fist hanging onto a vine. The tag ends, can then be affixed to suitable anchor where needed. The key here, is using a smaller diameter cordage, than the wire or coax itself.

The Prusik, along with similar ‘Friction Hitches’, can be used in any number of applications in Ham Radio. e.g. Anchoring coax, joining linked antenna elements, power cords, and adjustable guying. The list is long, wherever strain relief is needed.

I would encourage you to tie it, try it, test it, and judge for yourselves. As well, I would encourage you to check out other useful climbing friction hitches… YouTube is a great place to start. I hope you find this useful afield, and to hear you ‘On the Air!’

73! de W7UDT (dit dit)

W7UDT, ‘Rand’, lives and operates near Boise Idaho, with his lovely wife Stacy. Portable QRP operations, along with his Jeep and Harley are his ‘vices.’ Your comments and questions are welcomed. My email is [email protected].

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

POTA with the Icom IC-703 Plus: Working a serious SWR problem first, though!

26 Comments

If you’ve been here long, you’ve no doubt noticed that I have a sizable collection of QRP radios I take to the field.

Although I have some favorites, I try to rotate all of my radios in the field and even pair them with different antenna combinations as much as possible. If I only owned one field radio, I’d shake things up by pairing my one radio with different antennas deployed different ways during my POTA/SOTA activations.

I get a real thrill out of testing different combinations, actually, and I feel like it keeps me on my toes because I don’t get too comfortable with any one setup in the field.

No doubt, using a wide variety of radios gives me a more informed perspective when beta testing or evaluating new radio models.

That said, there is one radio in my collection that has been overlooked too many times: my Icom IC-703 Plus.

Many of you have noticed this, in fact.  I’ve gotten several emails and comments asking, “So Thomas…when are you taking the 703 out again–?” 🙂

When I purchased the ‘703 from my buddy Don a couple years ago, I imagined taking it to the field very regularly. I always thought it was a cool little radio and with its built-in ATU, it’s quite compact for a tabletop-style rig.

Thing is, each time I’ve taken it to the field, I’ve had issues with the electronic keying that I did not have when using it in the shack. It’s quite sensitive to RF, so end-fed antennas seem to create unwanted dits and dashes in the keyer.

The simple fix, I hoped, was simply using an in-line common mode choke to keep the RF away from the radio. Thing is, the IC-703 has an SO-239 antenna port and two of my common mode chokes are BNC. I meant to purchase a BNC-to-PL-259 adapter at the Shelby Hamfest, but picked up the wrong item (I should have been wearing my glasses).

Then I remembered that my Chameleon 50′ RG-58C/U cable not only has an integrated in-line choke, but also PL-259 connectors. This could work! Continue reading POTA with the Icom IC-703 Plus: Working a serious SWR problem first, though! →

Antennas, Guest Posts, Homebrew, How To, News, Portable, QRP

Sam builds a tiny tabletop HF antenna

18 Comments

Many thanks to Sam Duwe (WN5C) who shares the following guest post:

A (surprisingly good) tabletop HF antenna

by Sam Duwe, WN5C

I recently built a tabletop QRP HF antenna for 17 and 20 meters, in the spirit of the Elecraft AX-1, so I could operate at lunchtime on the campus where I teach. My wants were something small, that would fit in my work bag, that didn’t require a tuner, and could work on a couple of different bands. But on a lark I decided to attempt a POTA activation at Lake Thunderbird State Park (K-2792) pairing this antenna with my Penntek TR-35 QRP CW transceiver. I figured I’d maybe get one or two QSOs and then switch to a long wire in a tree. But what happened amazed me.

I talked to seemingly everyone. Beginning at 9:00 AM September 26th I worked both 17 and 20 meters for an hour and a half and made 37 contacts from across the country. I even had a Swiss guy call me back on 17 but he faded before we could finish. This antenna, at least as a CW POTA activator, works. Granted conditions were very good, but I’ve replicated this multiple times in the past few weeks, just recently at a picnic table in the parking lot of the Route 66 Museum (K-8644) in Clinton, OK (there is quite a thrill in urban activations).

It has also reasonably low profile and very quick to setup and take down. It is also quite a conversation piece when I set it up at school. I elevated the counterpoise by attaching it to a nearby oak and an interested undergrad sheepishly asked if I was listening to the tree!

The build is pretty simple. Physically the antenna consists of a small painters pole from Walmart and an old tabletop camera tripod. I found a nut that fit the screw portion of the tripod and hot glued it into the orange connecting section of the pole. That way the tripod can then be screwed onto the pole. The RF parts of the antenna consist of a 38” telescoping whip that I scavenged from the rabbit ears antenna that came with my RTL-SDR. It connects using the original connector which was hot-glued into a hole I drilled into the top of the painters pole. I found similar small 3 or 4-foot whips from AliExpress for cheap and these would probably work fine.

I then soldered a long length of speaker wire that was wound into two coils: the top for 17 meters (24 turns) and the bottom for 20 meters (25 turns plus the former 24-turn coil). The speaker wire was the soldered to the center of a BNC connector which I hot glued and taped to the pole. I soldered a short piece of wire from the shield of the BNC for the counterpoise and added an automotive spade connector to attach to a 17-foot length of wire. I also included a switch between the coils and the BNC connector to select either just the top coil (17 meters) or both coils (20 meters) using solder, hot glue, and tape.  I then covered my shame in silicone tape.

The most time-consuming aspect of the project was tuning the antenna. It required trial and error to first tune the number of turns on the 17-meter coil and then the 20-meters coil. I extended the counterpoise (for me it’s best when slightly elevated) and the telescoping whip. I performed the tuning with the whip not fully extended to give room to tune in the field. Using a nanoVNA was useful here, as was soldering a pin to the wire to poke through the wire at various parts of the coil to find the best SWR.

In use, the antenna can be affected by both body capacitance and how the counterpoise is situated, so I found that an in-line SWR meter was helpful in making sure all was well. Once set up it is easy to fine tune by just adjusting the whip length. 1.5:1 SWR is about how well I can tune on average. Obviously if you have a tuner you would just have to get it close.

There are a million variation on a small base-loaded vertical antenna, and you can definitely improve upon this design. And, besides the super well-built and elegant AX-1, QRP Guys sells an interesting looking kit, and there are some good 3D printed designs I might want to try out. But regardless how you go about it, it might be worth giving a tiny antenna a shot.

72, Sam WN5C