Category Archives: Portable

Rich re-activates Santa Fe Prairie State Park with QRM-busting in mind

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



Field Report: Testing a horizontally-polarized antenna at a high QRM POTA site

by Rich (KQ9L)

I wanted to give a quick follow up report from Santa Fe Prairie State Park (K-7839).

As you may recall I wrote up my POTA activation from this park on Oct 23, 2022. I made 15 Q’s that day but deep down felt I could do better. The setting of the park is quite industrial and consequently the man made noise is bad. Reflecting back on this activation, I feel that the limited the number of QSO’s I made that day was due to this QRM.

I resolved to try again but this time my objective was to figure out a solution to mitigate the effects of the QRM on my QSO count. Thinking about the problem, I recalled than manmade noise typically is vertically polarized and therefore for my second attempt, I decided to test this and use a horizontal antenna.

As luck may have it, here in Chicago we continue to experiencing unseasonably warm weather and my work schedule wasn’t too busy on Thursday, November 3, 2022, so it seemed like a great chance to put my theory to the test.

For the antenna, I decided to use one which I have owned for awhile, but have never used. I had purchased a RadioWaves Double bazooka from an online retailer some time back when they were on sale and planned to set up it a flattop dipole.

If you recall from my description of the Santa Fe Prairie State Park, there is a scenic overlook which has a tree mounted pulley system perfectly spaced to mount a 20m dipole. Although this would be the first time I used the system, it turned out to be a well designed and intuitive hoisting solution to use.

The “pulley” is actually an eyelet with paracord running through the eyelet. The paracord is in a continuous loop just like rope on a flag pole. By employing a simple overhand knot I secured the end of the antenna to the paracord and hoisted the antenna up into the tree about 20ft. It literally took a few minutes and I was ready to go.

Antenna was fed with my RG-316 feedline with built in common mode choke. Since a dipole is a balanced antenna system, it really doesn’t need the choke, but it was the coax that I had packed with me and I figured it wouldn’t cause any harm or negatively affect my test. I was QRV by 3:20pm, and anxious to get on the air. Continue reading Rich re-activates Santa Fe Prairie State Park with QRM-busting in mind

Sam sources a larger tuning knob option for the Penntek TR-35

Many thanks to Sam Duwe (WN5C) who writes:

John (AE5X) had suggested a while back finding a larger tuning knob for the Penntek TR-35.

I was striking out in finding one that fit but had to put in a Mouser order and thought I’d give this knob a shot (Mouser # 706-11K5013-KFNB) and I really like it!

I accidentally bought the gray version and had to paint it black. It’s shiny because of the clear coat and rough because of sanding and because I’m apparently awful at painting, but I find that it fits with the plastic bezel of the radio.

With the optical encoder it really glides, and totally changes the feel of the radio. Pretty good deal for $2.36.

Thank you for the tip, Sam!

Jay discovered that his first CW POTA activation wasn’t scary at all!

Many thanks to Jay (W1ASP) who, last week, sent me a note about his first POTA CW activation. I asked if he’d consider writing up a short field report about his experience to share with others and he was happy to do so. Thank you, Jay.


Halloween POTA

by Jay (W1ASP)

Halloween doesn’t have to be scary.

I set out to Bear Brook State Park (K-2643) for my first CW POTA activation.

Bear Brook is relatively close by, its the largest state park in New Hampshire with over 10,000 acres. There’s camping, hiking and biking trails along with an archery course and plenty of swimming and fishing areas.

I didn’t give it much thought about what day it was, just that I had the time to do an activation and it was nice out, what a perfect opportunity to break in the newly assembled kit.

I decided on a spot next to the water and as luck would have it there was a picnic table right there. I took out my gear, set up and proceeded to tune around and listen. The band seemed pretty quiet. I wasn’t sure if I’d get enough QSO’s in to make it an official activation. I decided on 14.038 MHz, I sent QRL? I then held down the memory button, took a deep breath and hit it again to transmit: CQ POTA DE W1ASP

I waited a second or two and used the memory keyer once more, again nothing. I went to the POTA website on my phone and added my activation.

The memory keyer was used for a third time, I noticed a message pop up on my logging app, the Reverse Beacon Network spotted me. It wasn’t too long after, the first call came back to me!

I was nervous and fumbled a bit here and there but once I took my time I was fine, sending their call back and TU UR 599 599 NH BK. I cheated a little and left the CW decoder enabled. I wanted to be sure I had the call correct as I logged my 13 QSO’s. (I swear the 13 wasn’t intentional.) for my first CW park activation! I only realized that it was Halloween while walking back to my truck.

I thought to myself, “that wasn’t scary at all.”

Once I decided that, as an activator I’m in charge of the QSO, I relaxed and it was a lot of fun. I may have made a few mistakes but everyone was patient with me. I later received an email from another Ham in Delaware. He was using the same radio, and referred to them as the perfect “picnic portable radio” we emailed back and forth a few times and I look forward to hearing him on the air again soon.

 

The week before, I finished building my second QCX Mini. The first kit I built was for the 30 meter band around this time last year, this second one is a 20 meter version. I love these little radios, there’s something about these little transceivers that I just can’t seem to put them down.

I took my time making sure it was working properly, I hooked it up in my shack and I had my first QSO with another POTO activator in Maryland just over 400 miles away.  To say I was excited is an understatement!

I planned on putting together a kit about a month ago for POTA and eventually SOTA with the QCX Mini as the radio. I decided on using a small pack, I wanted it to be a self contained kit that had everything I needed to do an activation and nothing extra.

I keep the wire and radios together,  and depending what band I choose to operate on is the one I pack. I’m considering a third kit; maybe a 10m version? I threw the EFHW matching transformer in the bag along with a notebook, mechanical pencil and a battery pack I put together using four 3.2v LifePo batteries. The paddle I’m currently using is a stainless paddle I found on online with a mini CW paddle for backup and set of folding headphones.

I’m looking forward to my next park, this was a great experience. I wanted to learn CW since I became a Ham in 2016, that’s another story of what got me into Ham Radio in the first place.

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

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

Rich’s Triple Activation Day!

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!

How Paul logs while operating pedestrian mobile

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!

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

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!

Sam builds a tiny tabletop HF antenna

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

Jonathan demonstrates using a K7QO noise bridge and shares a 3D printed OM0ET loop mount

Many thanks to Jonathan (KN6LFB) who shares the following in reply to my recent post about tuning mag loop antennas:

Hi Thomas,

I made a short video showing the use of a K7QO noise bridge from QRPguys to tune a mag loop antenna:

Also, inspired by your post, I dragged my OM0ET magloop up a mountain today for a POTA activation. I used a 3D printed tripod adapter of my own design that allows me to mount it on the collapsing legs from the Buddistick Pro. It makes the whole package a lot more manageable and light weight than carrying a camera tripod.

I had a successful activation of K-4454 on 20 meters, and thought you might enjoy some photos of the setup:

I’ve uploaded the design to Thingiverse at this address:

https://www.thingiverse.com/thing:5589250

73,
Jonathan KN6LFB

Wow! Thank you Jonathan. That short demonstration prompted me to order the K7QO noise bridge kit from QRPguys this morning. In fact, I plan to build this and keep it with my loop antenna as it’ll pair so nicely with my IC-705 and TX-500!

Thank you, also, for sharing those 3D files! I love that field setup at K-4454!

Mark’s first POTA activation with the Penntek TR-45L

Many thanks to Mark (W8EWH) who shares the following field report:


An Afternoon POTA Activation with the PENNTEK TL-45L

by Mark (W8EWH)

I have a hard time resisting new QRP radios, and I have an equally hard time resisting getting outdoors when late October brings 70F (21C) temps to Michigan.  Days like these are especially sweet given we saw the first snow here last week (no accumulation – but still…). For me there was no better way to enjoy this unexpected weather gift than with an early afternoon POTA activation with my newest QRP radio, the PENNTEK TL-45L.

The TL-45L is the latest radio from WA3RNC, joining the TR-35 and TR-25 in his online store.  It’s a 5-band, 5-watt CW transceiver covering the 80, 40-, 30-, 20- and 17-meter bands.  That in and of itself is not particularly noteworthy.  But when you look at this radio, you’ll immediately see what makes it different.

The retro look for me is unlike anything I have seen in a modern QRP radio.  It frankly looks like it was removed from an Apollo Command Module.  From the front meter to every knob and switch, this radio just begs to be fiddled with.  And each knob and switch serve a function that means no longer needing to dig through menu after menu to find where the narrow filter is switched in because of nearby QRM, or so I can slow down when my CQ POTA is responded to by a slower CW call.

The speaker is located on the (left) side of the radio, a feature many smaller QRP radios don’t have, though headphones can be used via a front mounted jack.  The radio sounds great – I think the radio’s case provides a nice sound chamber.

The TR-45L comes with a couple of options, neither of which I chose to add to my order.  One is a built-in rechargeable battery (5200 mAh), and the other an antenna tuner.  I have plenty of batteries, and normally use resonant antennas.

With the Monday late morning temperature approaching 70 I packed the car with radio gear, and my wife, and we headed out to Island Lake State Recreation Area (POTA K-3315) to activate this park with the TR-45L for the first time.  My wife is not a ham but often comes with me to POTA activations.  While I set up, activate, and then pack up, she enjoys the outdoors with a magazine and crossword puzzle, and sometimes, like today, a light lunch.  Usually, once the activation is complete, we’ll go for a hike on park trails.

Island Lake is about a 20-minute drive from my house.  Its 4000 acres is a mix of open fields and hardwood forests surrounding Kent Lake and the Huron River.  Today it was warm enough that someone was using a paddle board on the lake.

I have found a set of picnic shelters on elevated ground overlooking Kent Lake as a great place from which to activate.  I worked North Pole Alaska from this location on 20M CW using my IC-705 with 10W into an EFHW last May.

Once at the shelter I set up my EFHW (KM4ACK kit) in a sloped configuration using a conveniently located mature tree and my throw line.  It was roughly in an East/West orientation. Over the preceding weekend, I added PowerPole connectors to the provided power cord, and programed both internal CW keyer memory slots.  These are activated using either dit or dah paddle when I toggle Play using the provided switch.   Of course, I did a little POTA hunting using the home antenna to familiarize myself with the TR-45L’s operation.  The learning curve is short with nothing hidden deep behind any menus.

With the radio and antenna ready to go, I set up HAMRS on my iPad, spotted myself on the POTA website, and started calling CQ POTA on 14.0615.  Over the course of the next 35 minutes, I worked a total of 30 stations on 20M and 40M (most on 20M) at which point I basically ran out of hunters.  Not bad for a weekday afternoon.  I packed up and went on a couple mile hike with my wife.

The TR-45L is an absolute joy to use.

I forgot to put it in CW Narrow mode at first, and when nearby QRM popped up, I was able to add this in with the throw if one switch. QRM gone.  (Note, this setting – wide vs. narrow filtering – must not be retained after the power is shut off or the battery is disconnected.)

It sounds wonderful.  I used the side speaker the whole time as my wife doesn’t seem to mind, although the random guy who wandered in with a laptop to get some work done on a warm fall day decided to find somewhere else to work.  There are front mounted jacks for headphones, paddles and a straight key.  Even a rear mounted jack for an external speaker.  The built-in speaker can be turned off and on via a toggle switch.  The two CW memory slots are easy to fill using your paddle.  The front meter can show power output or SWR based on toggle switch position, and you are alerted to high SWR via a front mounted red LED.

I waited a while to get this radio.  Recent supply chain issues caused unexpected delays, but it’s available for order now in factory-built form and most definitely worth the wait.  Kits will eventually be available.  Check out all the TR-45L details here.

Mark Yergin

W8EWH