Category Archives: Antennas

Antennas, Articles, Guest Posts, News

Chameleon MPAS Lite: Using the coax shield as a counterpoise and how this might affect directionality

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

Portable Operation Using a Vertical Antenna Without a Counterpoise Wire!

by Dale (N3HXZ)

In a previous article that Thomas was kind enough to post, I ran experiments to determine if the counterpoise wire orientation of the Chameleon MPAS LITE antenna system in the vertical configuration in any way shaped the antenna pattern.  The configuration of the antenna is shown below.

The system consists of a 17’ telescoping whip antenna, a matching transformer, a 50’ coax cable with an in-line RF choke, and a counterpoise wire (60’ long, but unwound to only 25’ for use in the vertical configuration).

Subsequent studies I performed have reinforced my earlier conclusions that the positioning of the counterpoise wire in this setup does not appreciably shape the antenna pattern. One of the comments from my post came from Stephan (HB9EA). He commented on the fact that the coax cable is indeed a counterpoise via the coax shield and that in fact my system set-up had two counterpoises.

It was Stephan’s comment which led me to contact Chameleon Antenna to discuss counterpoises with the MPAS LITE antenna in the vertical configuration. I communicated with the Director of Research and Development group at Chameleon and found out some interesting information that I wanted to pass on.

He mentioned that the system can be used with the coax cable acting as the lone counterpoise as long as the coax cable is at least 25’ long, and preferably 50’ long.  The coax should be spread out and not coiled along any portion of its length. It was stated that the counterpoise wire provided with the product should be used with short-length coax cables.

With regards to a counterpoise orientation shaping the propagation direction, he stated that it is generally accepted that using only the coax as a counterpoise tends to have the antenna pattern slightly favor the direction in which the coax is laid out. Adding the counterpoise wire in a direction opposite to the coax would tend to balance out that pattern. Having the coax and counterpoise wire at some angle to each other introduces variables that make it difficult to determine the antenna pattern.

My initial study had the counterpoise wire oriented at an angle to the coax cable.  I mentioned that my initial study showed that orientation of the counterpoise wire did not seem to appreciably shape the antenna pattern, and he agreed. What is unknown is the overall degree to which the coax cable shapes the antenna pattern with or without use of the counterpoise wire.  This is an area I am currently investigating.

Operating the MPAS-LITE vertical configuration with only the coax cable as a counterpoise was an intriguing thought.

To test it out I teamed up with Jim (KJ3D) for a SOTA activation on W3/PT-003 (Seven Springs). We both deployed the MPAS-Lite with only the supplied 50’ coax cable attached. Coax cables were laid out in a straight line. One cable was oriented southeast, the other one oriented east. We operated on 10 Watts in CW mode. The activation successfully worked all bands from 40M to 10M. I operated an Elecraft KX2 and Jim operated a KX3. The internal tuner of both rigs easily obtained a 1:1 match across all bands.

A map of the QSO’s is shown below. Note that despite the coax cables facing to the southeast and east, we easily worked stations in the opposite directions. Hence any minor shaping of the antenna pattern by the coax orientation does not appear to impede successful communication in all directions.

In summary, the MPAS-LITE antenna system in the vertical configuration utilizing the 50’ coax cable with an in-line RF choke as the single counterpoise has been demonstrated to perform well in the field.

For portable operation where fast deployment and simplicity is paramount, using the furnished coax as a counterpoise is a quick and dirty way to get the antenna erected and on the air with reliable communication capability. Eliminating the counterpoise wire allows for quicker set-up and tear-down, and one less thing to put in the backpack!

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

Business Travel & POTA: It’s as simple as One … Two … Three!

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by Vince (VE6LK)

As always there are lots of links within the article. Click one! Click them all! Learn all the things! 🙂

The backstory

For those of us that work from home there are good and not-so-good things about it. One of the not-so-good things is that I’m not getting out somewhere every day like I used to, thus I embrace corporate travel as it represents a mini-escape from the day-to-day activities that would normally happen.  It also gives me an opportunity to operate in the field and away from the comfort of sites nearby my home.

In late September I was in the Edmonton Alberta area for work and, as always, I brought along a set of gear to play radio. Where I’d normally drive up and park my F-350 within the boundaries of the park and operate from the cab of the truck, this time I was in a rental vehicle so I had to be well-equipped for the unknowns. I also didn’t pre-plan my stops like I normally would, I just wanted to roll up and do my best to make it work.

These would all be CW activations at QRP power and are part of my 200 CW activation contacts per month personal goal to improve my CW skills. (Spoiler alert: I hit the goal while writing this article!) See below for my kit list that made this possible.

Not really pre-planning an activation is a stark contrast to how I normally roll as I usually pore over maps and satellite views on multiple websites to visualize where the park entrance is and where I’ll set myself and what I may encounter for surroundings when I get there. I know exactly where I’m going and just about down to the parking space. I build a set of kit up to support that/those activation/s.

With the lovely autumn weather we were experiencing in Alberta, my plan was to activate after work opportunistically around Edmonton – something I’d not yet done despite many trips to the area – and set up and operate right around 0000z. This time is after my workday, so a nice mental break from the day’s activities before kicking back for the evening. I think to my self that I’ll roll into a site nearest to where I was working arriving just before midnight UTC (1800h local) and get set up and start calling once the clock ticked over into a new day. From there I would then head to the hotel (or home) and grab a bite to eat and close my day off on a high note.

Continue reading Business Travel & POTA: It’s as simple as One … Two … Three! →

Antennas, Field Radio Kits, News, Portable, POTA, QRP, SOTA

I’m in portable field radio kit mode…how about you? Care to share?

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A portable field kit:  it’s a seasonal thing.

In the early fall and spring, I go over my QRP radios and give serious thought to how I’ll build compact field kits around them.

Why? I’m pretty sure it’s the pending change in weather that’s the catalyst.  The temptation to get back out there and make some contacts.

Then again, any excuse:  I absolutely love building field kits, and fortunately it never gets old.

The radios I’m considering at present are my MTR-3B (named Threepence) and KX1, now named Audrey. (Yep, I chose “Audrey”…thank you for all of the amazing suggestions!)

Both of these are ideal little radios for kitting out because they’re so compact and truly made to be taken to the field.

One of these two radios––and I haven’t decided which one yet––is going to live in my EDC bag.

The Tom Bihn Stowaway in black has been my EDC bag for many years. I’ll need to pay attention to the weight and bulk of this field kit, because I’ll be lugging it pretty much everywhere.

I’ve got some ideas and a couple of pouches in mind, so this will all start coming together soon.

But first…

Care to share your portable radio kit?

One of the things I enjoy doing when I’m putting together a new field kit is to check out what others have done.  It’s a great way to get some fresh ideas…and besides, it’s  just plain fun to compare notes.

If you would like to showcase your field radio kit on QRPer.com, please send a short write-up with photos detailing how/why you built your kit as you did, and list all of the components with links to the manufacturers.

We’ll not only publish your field kit article as a post, but also on this new Field Radio Kit Gallery page I created!

We only ask that you send your own original ideas––and not just a link to another website article or video––as we’d like this content to become part of the QRPer archive. That way, if an external link is removed, it’ll still be safe and sound here. (We take our archiving seriously on this site.) Of course, we welcome links to blog articles and videos in your post.

Simply send your information via email to my callsign K4SWL at QRPer.com.

Interested? Feel free to get in touch!

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

N5FY’s First CW POTA Activation!

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My First CW POTA Activation

by Joshua (N5FY)

As I often do, I hunted yet another CW POTA activator during my lunch break while working from home.

I have been learning CW for most of the year. Early on, I realized that with a bit of practice sending, and after listening to recordings of POTA activations, like those from Thomas, I could reliably send the proper exchange needed to hunt a POTA activator.

If you can give your call sign, signal report, and state abbreviation, you can make the contact. I started early on with just the basics and then added some of the common “extras” like GM for good morning, TU for Thank You and then 73. Not only is this great practice for getting on the air sending CW, it’s also very rewarding while learning CW. The exchange is short, standard, and easy to follow with a bit of practice.

CW Practice with the Morserino32 and a Cup of Coffee
CW Practice with the Morserino32 and a Cup of Coffee

Once I finished my upgrade to Extra I focused all my spare time, not much though truth be told, on practicing CW.

At some point this summer I set the goal to Activate POTA/SOTA during the W4G SOTA campout this fall. This really wasn’t an aggressive goal, one I figured was attainable but also one that I could hold myself accountable to even knowing I had a very busy summer ahead of me.

W4G SOTA Campout Summit View Yanah Mountain Bald
W4G SOTA Campout Summit View Yanah Mountain Bald October 2022

During one of the LICW Club classes I heard again that their goal is to get Hams on the air to make a QSO. I thought to myself, yes, that is great, and I want to do more, but I know I have made many QSOs in CW on the air, albeit very short and simple ones. So, I was curious how many.

I jumped on the POTA site and looked up my statistics. I was surprised at how may hundred I had, and yet at the same time, I was a bit disappointed. It’s not that I wanted to have made more CW contacts, it’s that I realized that they were ALL from hunting and not a single one was from calling CQ.

So, I changed my goal.

I know that Hams, especially CW operators, are a great bunch of people and they want to see new CW operators succeed, so there is lots of patience when you call CQ. So, I decided to move up my timeline. This was on a Thursday, and Saturday was a likely candidate for a POTA outing, why not–?

Saturday was my birthday, and I knew I could get away with some personal free time in the morning where I could dive in and call CQ POTA DE N5FY. The next day, Friday, I firmed it up, I would head out in the morning, bring the new to me KX2 and see what happens.

Surprisingly, I was much less nervous than I expected, I had told myself that it wouldn’t help anyways to be nervous so just do it and see what happens. I made it to my local park, to the picnic table I frequent, then setup a No Transformer 2-Wire antenna with the KX2. One press of the ATU button and I had a 1:1 match on 40m band.

Of course, I have great timing. I could not believe the stations on the air on 40m. I never did look but there must have been a contest. I moved up and down about 20kHz and there were stations everywhere! I called “QRL?” on 2 different frequencies and had a reply before I landed on open frequency where I could call CQ.

N5FY First CW Activation KX2 Setup
N5FY First CW Activation KX2 Setup

I had not scheduled the activation; I knew I had a bit of cell phone coverage at this park, so I set the CQ POTA message to calling while I posted a spot.

After two calls, I had my first call back. It was time!

I could have freaked out here, but I was too focused on decoding to even be nervous! Of course, I had to send a partial call and a “?” once or twice to get the full call right. Of course, I made some keying errors. But the caller had patience and worked me and we made the QSO. Now I was really excited!

I called CQ and someone sent me back dits and dahs, and I decoded what they were sending! Boy, this was fun! I continued to call CQ POTA, and tried my best to decode the replies, several pileups, and lots of “?” sent by me. But I was making contacts and having a blast!

After a couple of silent CQ calls later, I switched to 20m. And, again, started to get replies back as well as a couple small pileups. In the end, there were a couple call signs that I could not look up, l had a letter or two wrong, but with almost 20 in the log I knew I had an activation and boy was I happy!

N5FY First CW Activation QSO Map
N5FY First CW Activation QSO Map

Looking back on the activation, and after talking to another Ham, it occurred to me why I wasn’t as nervous as I thought I might be.

You see, when you are the Activator, when you call CQ, the ball is in your court, you invite people to call back and they are there for you. I almost get more nervous hunting as I don’t want to slow down an activator or run over another caller. But when you are the one calling CQ, it’s your game!

Of course there were several hiccups along the way. For one, it got HOT sitting in the sun. I ended up deploying my hiking chair on the table as a sunshade and pulled a portable fan out of the car. Even the action camera overheated while recording the activation. I couldn’t get the KXPD2 paddle to key the KX2 on 20m when I first got setup. And of course, I had lots of sending errors (although fewer than I expected to have) and sent a A LOT of “?” asking for a repeat.

That said, I am very glad to have jumped in and will continue to activate CW going forward as I continue to build my CW skills. For me, confidence in the ability to Activate on CW is great motivation for practicing, which again, is my biggest learning. If I want to be a good operator, I need to put in the effort, and going out to play radio is one extremely fun way to practice!

73 Joshua N5FY

Antennas, Field Reports, News, Portable, POTA, QRP, Videos

POTA with a 20 Meter Vertical Delta Loop and the Elecraft KX2!

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There’s a portable wire antenna design I’ve been wanting to put on the air for POTA and SOTA for what seems like ages: a 20 meter vertical loop.

I mentioned in a Ham Radio Workbench podcast episode a few months ago that I planned to build a field-portable delta loop antenna and that led to a mini discussion about configurations, feed points, height off the ground, etc. and how all of those factors can influence the characteristics and dynamics of the antenna.

Vertical loops are pretty fascinating and incredibly effective.

Delta loops are super easy to build (no more difficult than an EFHW) but this summer has been insanely busy for me and I simply hadn’t gotten around to it yet.

Then my good friend Joshua (N5FY) who runs tufteln.com sent me a prototype 20M delta loop in the mail. We’d been talking delta loops and he couldn’t help but build one. He asked that I take it to the field and put it on the air, then give him any feedback and notes I might have.

Joshua’s design incorporates a 4:1 transformer and was cut to be resonant on 20 meters. I’d actually planned to build one identical to this because the type of loops I’ve deployed at home have been fed with ladder/window line which isn’t as portable as something I could feed with RG-316.

Holmes Educational State Forest (K-4856)

On Friday, September 1, 2023, I grabbed the delta loop antenna and the KX2, then made my way to Holmes Educational State Forest.

I knew that Holmes wouldn’t be busy and that there were a number of options for spots to set up.

After a little scouting, I found a great site to set up the antenna.

I planned to set up this antenna as close as I could to an equilateral triangle with the apex up about 30 feet and the feedpoint in the middle of the base of the delta.

Deploying the antenna in this configuration meant that I only needed one line in a tree to hoist the apex of the delta and two lines to pull out the corners of the base.

I brought along some paracord with tent stakes to secure the base corners of the loop. In the end, though, I simply attached the paracord to trees instead of using the stakes.

I (somewhat reluctantly) made a video of the entire activation including the antenna deployment. I wanted to take my time deploying this antenna for the first time, so the antenna deployment section of the video is much longer than usual.

You absolutely cannot see the loop in this photo, but it’s there…I promise!

In the end though? It wasn’t as difficult as I thought it would be. The last vertical delta loop I deployed was a 40 meter loop which is roughly double the size–in my head I was expecting the aperture to be larger than it was.

My arborist line and 12 oz weight hanging to provide a gentle tension to hold the apex of the loop up.

The 20 meter loop is actually pretty compact and almost as easy as setting up as an inverted vee.

With my loop properly deployed, it was time to hit the air! Continue reading POTA with a 20 Meter Vertical Delta Loop and the Elecraft KX2! →

Antennas, Field Reports, News, Portable, POTA, QRO, QRP, Reviews

Golden Hour QRP POTA Activation with the REZ Ranger 80 Portable Vertical Antenna

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On Sunday, August 20, 2023, en route to check in with my parents, I popped by Lake James State Park for a little early evening POTA fun.

In the car, I’d pack the Elecraft KX2 kit and I still had the REZ Ranger 80 vertical antenna system on loan from REZ Antennas (it’s since been returned to them).

The last time I deployed the REZ was on Mount Mitchell in some pretty sketchy weather.  While I recorded a couple of short videos, I didn’t record a full activation video since we were having a family picnic that day.

Before sending the Ranger 80 back, I wanted to fit in a proper activation showing how I deploy the antenna, how I tuned it for the first time, and how it might perform on the 40 meter band.

Lake James State Park (K-2739)

It was golden hour at Lake James and the park was bustling with activity. There were kids running around, parents chasing them, and several families cooking out at the numerous picnic sites.

I sought out a location that was private and quiet mainly because the Ranger 80 antenna has four 31 foot radials, thus a large footprint; I didn’t want children, pets, or anyone tripping on the ground radials.

Fortunately, one of my favorite spots overlooking the lake was free, so I could simply set the Ranger 80 up in the woods where folks weren’t walking.

The Ranger 80 is super easy to deploy: simply extend the vertical, attach it to the top of the base, then attach the stainless spike to the base and plunge the entire thing into the ground. Next, you deploy the four radials and connect it to the base of the antenna.

It only takes a couple of minutes especially since the counterpoises are wound using the over-under method. I simply tossed each line into the woods and didn’t worry if they were all lying perfectly on the ground.

Note to REZ: Consider offering optional high-visibility counterpoise wires–for those of us setting up in busy parks, it would make the ground radials more conspicuous to passersby.

Next, I needed to tune the Ranger 80 for the forty meter band.

Typically, when I use a sliding-tap tuning coil style antenna like this one, I turn on the radio and move the coil until I hear an audio peak, then I fine tune it by sending a “dit” on the radio, checking the SWR, and adjusting the coil slider.

That evening, though, I had my RigExpert AA-35 Zoom antenna analyzer so I set it to continuous SWR monitoring and adjusted the coil until I achieved a good match. Easy.

I should add here that when you use an antenna like this frequently, you learn where the best tap points are on the coil thus tuning becomes easier. My friend Alan (W2AEW) actually made a PVC rig for his coil antenna (click here to check it out).

With the antenna all set up and ready to rock-and-roll, I simply hooked up the Elecraft KX2, my VK3IL pressure paddles, and prepared the logs.

It was time to play radio! Continue reading Golden Hour QRP POTA Activation with the REZ Ranger 80 Portable Vertical Antenna →

Antennas, Field Reports, Guest Posts, News, POTA, QRP, Travel

An Accidental Three-State POTA Rove!

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An Accidental Three-State POTA Rove

by Joshua (N5FY)

I often find myself playing radio in the evening when I travel out of state for work. I especially enjoy adding another state to my list of activations. So, a trip to the Sioux City area was great, as I could activate in South Dakota and Nebraska, both new states to add to my POTA activations.

Of course, you are wondering how one accidentally completes a 3 state POTA rove,  so I’ll get into the details in a bit. Believe me though, it wasn’t because I had a fool-proof plan. I do believe that failing to plan is planning to fail. But in this case, a bit of luck and agility on my part, with the bands cooperating, and with the POTA hunter support, I did indeed complete 3 POTA activations, in 3 states, in under 2 hours!

Go Ruck Bullet fits inside the G2 ready for Travel

To be honest, I rarely put much effort into planning an activation while traveling as I simply may not have any time get out to a park, and of course, playing radio is not the purpose of my trip. I often find myself spending just a couple minutes looking at POTA locations before a trip and even may look last minute after I land, before I get off the plane, looking for a good POTA location. Maybe I like the urgent planning excitement, or maybe I don’t want the disappointment of not having the chance to go activate after spending time planning the outing? Again, I do recommend a bit of planning, so don’t exactly follow my example here.

As a result of my minimal planning I typically find myself with a very impromptu, “wing it” style activation. This trip was certainly no exception. I only had one evening to check off both South Dakota and Nebraska. There were parks which seemed readily accessible, but I hadn’t really verified activation numbers or best location on the park property to setup. I did save a few parks in the 3-State area, including Iowa.

I already had an Iowa activation, so I wasn’t as worried about hitting the IA park.

Once my evening freed up, the first day I was in the area, it was already a late in the evening, so I was in a bit of a rush as I headed to the first park. I figured I would hit South Dakota first then drop down to Nebraska and spend a bit more time calling CQ there according to how much daylight I had left.

POTA Park in 3 States surrounding Sioux City

I arrived in the area of the first park–a state park land. As I approached the boundary, I found a horse trail parking lot with some nice-looking trees for a throw line and wire antenna. As I was in a hurry, not needing a hike, I  knew this would work well. I’m not one to play radio from the car, but in this case, it would cut down a bit on the time needed so I could get to the second park.

I threw a line and pulled up my antenna. Within 10 minutes of parking, I had my station setup and scanned 20m to see what shape the band was in. I typically put up a 20m EFHW and hope for the best, and this usually doesn’t disappoint. I then setup my log and found a surprise. Continue reading An Accidental Three-State POTA Rove! →

Antennas, Field Reports, Morse Code, New Products, News, Portable, POTA, QRP, Skills, Videos

POTA on Mount Mitchell: The new REZ Ranger 80 and how to use the Over/Under method to coil wire and cable

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The REZ Ranger 80 antenna system ships with everything you need, including a nice backpack.

Back in March, I received an email from Mike Giannaccio (W5REZ) the owner of REZ Antenna Systems–he was curious if I’d like to check out his REZ Ranger 80 antenna system.

At the time, my plate was pretty full, so he arranged to send it to me on loan in July.

If you’re not familiar, the Ranger 80 is a portable vertical antenna with a tuning coil at the base that employs a sliding tap for tuning. The Ranger 80 will cover anywhere from 80 – 15 meters without needing any sort of external matching device (like an ATU).

The Ranger 80 Tuning Coil.

If you’re familiar with the Wolf River Coils antenna systems, then you’re familiar with this type of vertical antenna. The difference is that the Ranger 80 is built to what I could only describe as MilSpec standards.

Much of the Ranger 80’s components are CNC machined from premium materials. It sports a Delrin body, black anodized 6061 aluminum, and all stainless steel hardware.

This is not a featherweight antenna: it has the heft to match the caliber of materials used in its construction. It’s not an inexpensive antenna either–it’s currently about $560 US at DX Engineering.

The base of the Ranger 80: note the beautifully CNC-machined holes for the four counterpoises.

The Ranger 80 is also rated for 500W SSB and 250W CW/Digital–in other words, quite a bit more power than I’d ever use in the field, but this design will make activators and field ops happy that like to push some wattage.

I was curious how easy the Ranger 80 would be to deploy and tune, so on Sunday, August 6, 2023, I took it to one of my favorite parks on the planet.

Mount Mitchell State Park (K-2747)

I wasn’t alone on this trip: it was a proper family picnic with my wife, daughters and, of course, Hazel.

The weather was very moody that day–driving up to the park, we watched clouds and mists rise up through the trees like waves crashing on a rocky coast line. Continue reading POTA on Mount Mitchell: The new REZ Ranger 80 and how to use the Over/Under method to coil wire and cable →

Antennas, News, QRP, QRP Radios, QRPer Notes

QRPer Notes: 23cm on the IC-705, New Color Counterpoises, and Rekindling the NJQRP Club

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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!

1296 on the Icom IC-705

Many thanks to Alan who shares this video of VK3FS operating his Icom IC-705 on the 23cm band.

Video description:

If you enjoy SOTA, parks, microwave or radio in the great outdoors, then Icom IC-705 is the radio for you. Having received many accolades, and a long list of positives, some might say there’s one thing missing on the IC-705 and that’s the 23cm band.

The good news – is it’s a relatively easy fix with the help of a 1296 MHz transverter from SG Labs.

Chameleon adds color counterpoise kits to catalog

Many thanks to Don (W7SSB) who notes that Chameleon antennas has added color counterpoises to their product offerings.

Click here to check it out.

Efforts to Rekindle NJQRP Club

Many thanks to Dennis (K2DCD) who shares the following message sent originally by Larry (W2LJ):

Once again, I’ve been giving thought to attempting to pump new life back into the New Jersey QRP Club. For many, many years it was considered to be one of the top QRP organizations in the country. It ranked right up there with the NorCal QRP Club, the Colorado QRP Club, the New England QRP Club and others.

In the early 2000’s, due to the efforts of George N2APB and Joe N2CX and a host of others, the NJQRP Club reached its azimuth when it sponsored Atlanticon, the QRP confab of the Mid-Atlantic Coast. It was held in Baltimore and each year I was dying to go. But my two kids weren’t even really toddlers yet, and with Marianne and I both working full time, it was an impossibility.

Soon after Atlanticon ceased, it seemed the club started to wither away. Stalwarts became Silent Keys, others moved away and NJQRP started to become a shadow of its former self. There were a few times I met with other members at the food court of one of the malls near Princeton. There were also a few outdoor gatherings at the park in Grover’s Mill – the infamous landing spot of the Martians in Orson Well’s “War of the Worlds”. And then finally there was nothing.

So where does that leave us? The website was moved to its present URL location in 2016. As far as I can tell, there have been no updates. And in all honesty, except for the Skeeter Hunt, there hasn’t been much activity to update the webpage with. Whatever the members have been up to individually, there’s been no real effective means of communication between them.

George N2APB has moved to Tennessee and N2CX is a Silent Key. There’s no roster, so there’s really no way to tell who was a member and who was not, and what members if any have either moved out of the area or have become Silent Keys. And since the last iteration of NJQRP, there just may be a whole new generation of New Jersey QRP’ers anxious to meet their like minded brethren in the state.

So we start with a new beginning. I started a Facebook page. As of right now, it’s a public group and I think you can just join. I’ve also started a Groups.io group now that Yahoo groups are defunct. This group will be an e-mail reflector and our main way of keeping in touch with each other. If you’d like to join that, you’ll have to send me an e-mail ([email protected]) and I’ll send you an invitation to join.

Granted, it’s not much of a start, but it is a beginning. Hopefully, as the word spreads and QRPers in New Jersey and the surrounding area become interested, maybe we can start holding meetings, if we can find a location that is convenient for all.

I’d like to stress that while the New Jersey QRP Club will primarily serve local QRPers as far as any future live in person events go, there are no residency requirements. All are welcome and if we do meet in person, we can always incorporate a Zoom component as other clubs I belong to have been doing to include those who can’t attend in person for whatever reason.

It’s not my job to run the organization, that will be up to the members. I’m just going to try and re-launch it. So stay tuned – maybe we can light this candle and get this puppy off the ground!

72 de Larry W2LJ

Accessories, Antennas, Guest Posts, News, Portable, Reviews

Barry reviews the RigExpert AA-650 Zoom

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Many thanks to Barry (KU3X) for sharing the following review originally posted on his website:

Product Review: RigExpert AA-650 Zoom

by Barry G. Kery, KU3X

If you are building a ham radio station, whether it be a contest station, a station for working DX or just daily rag chewing, this may be the tool you need to help you maximize your signal.

The AA-650 Zoom is a very user friendly antenna analyzer. It is super easy to navigate through the menu to choose what task you want the analyzer to perform.

Let’s start with frequency range. This unit will cover from 100 kHz up to 650 MHz. To get accurate readings, you must enter three factors. You must enter, “Frequency, span and sampling points. “  Here is one of many areas where the AA-650 Zoom shines and that is, “Sampling Points.”

When you sweep a frequency range, whether it’s just the 20 meter band or maybe sweep from 7000 kHz to 30000 kHz, sampling points have a direct impact on the results.

Antenna analyzers do not take a reading one Hertz at a time. They take a reading at numerous points within your sweep range. You can select how many sampling points you want to use. The 650 Zoom gives you 5 options. They are 20, 50, 100, 250 and 500 sampling points.

Let’s say you want to sweep from 7000 kHz to 30000 kHz, like the usable frequency range of a 40 meter off center fed antenna. If you choose to use 50 sampling points, the 650 Zoom will take a reading at every 460 kHz in that range. Once the sweep is finished, the analyzer takes an average and fills in the display with an SWR curve. So it kind of guesses what’s between each point.

Now take that same frequency range but sweep it with 500 sampling points. The 650 Zoom now takes a reading at every 46 kHz.  Remember one thing: the more sampling points you use, the slower the sweep but the higher the accuracy. For single band use, I like to use 100 sampling points.

Most of the time, that’s all you need. But let’s say the antenna you are testing has some quirk at a given frequency. If your sampling points are set too low, your sampling points may not be close enough to detect the problem. So now the analyzer will not know there’s an issue and fills in the display with an average reading.

There are two ways to setup the analyzer for a frequency and range. To the left shows where you can manually enter the center frequency and the span of the sweep. Press the, “Frequency key” on the keypad to access this feature. Within that display, to the far left you will see meter bands. If you press the, “F key” on the keypad, a band will be highlighted. Use the up / down arrow keys on the keypad to select your band of choice. When you let up on the, “F key” the analyzer will program that band with a predetermined span.

The picture on the right shows yet another super easy way to set up the analyzer. To access this screen, press and hold the, “F key” and then press the zero key on the keypad. The rest is easy. Pick a number that corresponds to the band you want to check.

Top picture shows an SWR curve of my 40 meter beam. This reading was taken from my shack. Take note of the bottom of the display. The analyzer lets you know what the minimum SWR is at a given frequency. On the top of graph, the SWR is shown in relation to the pointer.

The top right picture shows the SWR of my 20 meter beam at a given frequency. You may find this feature useful for adjusting a manually operated transmatch or adjusting the tuned inputs of your home brew amplifier. On the bottom of the display, it shows return loss at 14150 kHz.

When you sweep a frequency, you can save the SWR plot in any one of the 99 non-volatile memory slots so you can retrieve them at a later date.

If you want to check more than one frequency at a time, like on a tri band Yagi or an off center fed antenna, the AA-650 lets you pick up to 5 different frequencies to check at one time.

Shown below are return loss figures for a low power 4 to 1 Guanella Current Balun. The balun was designed to be used from 80 to 10 meters. The sweep is from 2 MHz to 30 MHz.

Let’s talk OSL Calibration…

Using Open, Short, Load calibration is a way to cancel out your transmission line so you can take a reading of your antenna like you are attaching the antenna analyzer to the feed point of the antenna. Let’s take a 100 foot length of RG-8X as our coax used for testing antennas. Hook the coax to the 650 Zoom and run OSL Calibration. Once you do that, it’s like the coax is transparent. Continue reading Barry reviews the RigExpert AA-650 Zoom →