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Icom Amateur Radios Identified as Explosive Devices Used to Target Hezbollah

Icom IC-V82 handheld transceivers designed for amateur radio use have been identified as the latest device to deliver deadly explosions targeting members of Hezbollah. The identification of Icom radios follows an initial attack on members of Hezbollah in which pager devices were used to deliver deadly explosions.

Icom is investigating the reports of its radios being used in these attacks while Icom sales reps believe the radios identified are knock-offs. Icom is expected to release its findings on its website. The IC-V82 was discontinued in 2014.

Source: Washington Post

WINLINK TRAINING UPDATE

Date: 2024/09/16 12:07 (UTC)
From: WG5GK

Greetings:

The WinLink training will start on September 23 at 8:00 PM CT. You will need to be prepared prior to the start of training.

To be prepared you will need the following setup

o A computer with WinLink installed (no radio required) and dual monitors. One monitor for the A/V conference and the second for your WinLink session.
OR
o A computer with WinLink Installed (no radio required) and either a second computer/laptop or tablet. The first computer will run WinLink while the second computer/laptop/tablet will be used for the A/V conference.

o Internet access on both devices.

The WinLink training will take 3 to 4 one hour sessions.

I will send a Winlink message to everyone by 6:30 PM on the day of the training with the A/V conference link.

If you know other that want to attend have them send an email to WG5GK@winlink.org. (Don’t forget the //WL2K in the subject line) I have 5 slots available.

Sincerely,

Gus.(WG5GK)

RSGB to End Paper Based License Exams

Beginning January 1st, Radio Society of Great Britain (RSGB) will no longer offer paper based amateur radio licensing exams except for special educational needs. Already, 97% of all amateur license exams are conducted online remotely or within a club space. Additional costs and effort around paper based exams were cited as reasons to move to an all digital format. Key dates:

  • Paper exams continue until December 13
  • November 29 is the last day to book a paper exam
  • Paper exams will no longer be available beginning January 1

Source: RSGB

Advertisers and radio magazines

Today I received my copy of the RSGB RadCom. One large UK dealer has most of the advertising space. I have no idea what this must cost, but it must be a lot. If this major dealer decided to stop advertising, or advertised far less, it would have a major impact on the RSGB and the remaining UK radio magazine available on newsstands.

Without this one dealer, I suspect RadCom would have to shrink in size and the one remaining magazine radio amateurs could  buy in newsagents would enter terminal decline.

I hope I am wrong.

Happy 6th Anniversary to the NBN

On Wednesday the Nickel Belt Net celebrates its 6th Anniversary on the 40m band. If the band conditions allow check in with them on Wednesday afternoon and give them a hearty “Congrats” for a job well done.

73bob

Logs 18 Sept 2024

1494 2030 Coast FM via relay. SINPO 34433.
1629 2020 Radio Bluebird. SINPO 44433.
1638 2013 Radio Eigen Risico. SINPO 34433.
1665 2007 Radio Wilskracht. SINPO 44433.
5020 1650 Radio JVG. SINPO 34433.
5030 2000 Deltracks. SINPO 44433.
5880 2036 Radio Rock Revolution. SINPO 34433.
6205 1823 Laser Hot Hits. SINPO 54444.
6290 1725 Radio Ronalisa (pres). SINPO 34333. Relay of Dutch MW station
6300 1809 Radio Boomerang. SINPO 54444.
6925 1730 "Radio 6925". SINPO 54444. No real ID but in pirate chat as this. Later on 6880

Music from all over the map

FastRadioBurst 23 here with news of what the Imaginary Stations crew are up to. This Sunday coming on 22nd September 2024 there’s another episode of Skybird Radio International via the services of Shortwave Gold. The show which features an across the board selection from around this musical globe of ours will be broadcast at 0900/1300 […]

Dr. James Breakall, WA3FET, Receives Major Award from the RCA

Dr. James Breakall, WA3FET, Receives Major Award from the RCA

Wednesday, September 18, 2024 - 11:59
Wednesday, September 18, 2024 - 11:27
Submitted 13 hours 38 min ago by af8a.

Congratulations to long-time HamSCI member Jim Breakall, WA3FET, on receiving the Dr. Ulrich Rohde Award for Innovation in Applied Radio Science and Engineering from the Radio Club of America (RCA).

Established in 2023, this award recognizes significant contributions to innovation in applied radio science and engineering in the wireless industry to inspire future generations of wireless professionals.

'Dr. Jim' received B.S. and M.S. degrees in Electrical Engineering from Penn State University and a Ph.D. in Electrical Engineering and Applied Physics from Case Western Reserve University, Cleveland, Ohio. He has over 50 years of experience in numerical electromagnetics and antennas. He was a Project Engineer at the Lawrence Livermore National Laboratory (LLNL-Livermore, CA), and an Associate Professor at the Naval Postgraduate School (NPGS-Monterey, CA). He is currently a Professor Emeritus of Electrical Engineering at Penn State.

He began his career as a graduate student at the Arecibo Observatory in Puerto Rico, working on antenna analysis and radar probing of the ionosphere. At LLNL, he and his group worked on the development of the Numerical Electromagnetics Code (NEC), the first sophisticated antenna modeling program. Other significant projects that he has worked on were the designs of the HAARP facility in Alaska, both HF facilities at Arecibo, and the Kinstar low profile AM broadcast antenna. Dr. Breakall (electrical) and HamSCI member/supporter Tim Duffy, K3LR, (mechanical) designed the very popular Ham Radio Skyhawk Yagi antenna, and Dr. Breakall is the inventor of the Optimized Wideband Antenna (OWA).

Dr. Breakall is a member of several IEEE societies, Eta Kappa Nu, International Union of Radio Science Commission B, and the IEEE Wave Propagation and Standards Committee. He has been an editor for several journals. He is a frequent speaker at the Dayton Hamvention Antenna Forum.

He received the RCA Sarnoff Citation and is a Life Fellow of IEEE and a RCA Fellow. He serves as an RCA director and as the Co-Chairman and later Chairman of the RCA Technical Symposiums. He also serves on the RCA Scholarship Committee, Education Committee and Awards Committee, and Innovation Council.

- Thanks to the RCA website for the above details

QU-21C Mini Paddles

I’ve been toying with the idea of putting together a small radio kit based on my (tr)SDX or something similar, so I’ve been looking at small paddles to go with it. Browsing through eBay recently, I came across several listings for the QU-21C paddles. They were inexpensive, so I thought I’d order them and give them a shot. 

These paddles are nothing new; they’ve been around for a few years. (I’m definitely no early adopter.) The QU-21C paddles are made in China and mine are marked with the brand name, Magic Rabbit. From other reviews I have seen, there may be other manufacturers. So, the quality and packaging may vary. I paid about $24 USD from a seller (iDrone) that ships from the U.S., but you can find them listed for less than $20, if you don’t mind waiting for a shipment from China. 

Opening the package, I found the paddles are even smaller than I expected. The base is approximately .98 inch by .98 inch (25mm x 25mm) and 1 inch (26mm) tall. The overall length, including the paddles, is 1.9 inches (48.5mm). On my kitchen scale, the paddles weighed in at 1.25 ounces (34 grams). The paddles appear to be 3-D printed, but the quality is pretty good. The base of the paddles is magnetic, which is one feature that first drew my attention. 

Magic Rabbit QU-21C paddles with the rubber pad attached to the magnet. The pad looks a little ratty around the edges, because I removed it and decided to put it back on. I messed it up a little in the process.
Magic Rabbit QU-21C paddles with the rubber pad attached to the magnet. The pad looks a little ragged around the edges, because I applied it, removed it, and then decided to put it back on. I messed it up a little in the process.

The package I received included:

  • Paddles with a magnet attached to the bottom
  • 3-ft cable with 3.5mm stereo plugs on each end
  • Hex wrench for adjusting contact spacing
  • Two adhesive metal discs
  • Adhesive rubber pad
  • Plastic storage case that holds everything
Some of the accessories that came with it. The cable is inside the clear plastic storage box. The adhesive discs can be applied anywhere, so you can use the attach the paddles magnetically.
Some of the accessories that came with it. The cable is inside the clear plastic storage box. The adhesive discs can be applied anywhere, so you can use the attach the paddles magnetically.

My first impression was that the contact spacing seemed a little wider than I like. I used the supplied hex wrench and adjusted the spacing until the contacts were completely closed. Then, I backed off a little. 

I prefer a light spring tension on my paddles, but the spring in these paddles seems stiffer than I’m used to. Unfortunately, there’s no adjustment for that. So, I’ll just have to get used to using a little more force than my other paddles. 

I’m not sold on the magnetic base, though. The square magnet is fairly strong, but it’s highly polished. So, the paddles sometimes have a tendency to slide when I’m sending. I applied the rubber pad that comes with it, but that seemed to offer only minimal improvement. For now, I just hold them in one hand while sending with the other.

I’ve actually thought about trying to remove the magnet altogether, since it appears to be glued on. At least, it wouldn’t be attracting every ferrous object that comes near it. But, for now, I’m just thinking about it.

The QU-21C paddles during a recent activation, along with my trusty Palm Mini paddles are also shown.
The QU-21C paddles during a recent activation, along with my trusty Palm Mini paddles.

I had a chance to use the QU-21C paddles on a recent park activation. It didn’t take long to get used to them, and I had no issues with them at all. The paddles keyed reliably, without missing a single dit or dah.

Even with my spring tension and magnet gripes, I’m pretty happy with these paddles. These cheap paddles look like worthy candidates for field use. We’ll see how well they hold up over time.

72, Craig WB3GCK

Sept 18, 2024. A failure to communicate! Receiver Gain Distribution.

A Failure To Communicate! Those ominous 4 words have appeared in reports such as the 9/11 Commission Report, or in describing 20M Band Conditions and then extending even to an equipment breakd0wn. In short, these issues are the causal factors of a failure to communicate and not so much inside the communications itself.

The inside the communications factor can be seen in the current political environment where it is suggested that immigrants are eating your pets. It is clear the pet eating comments are to grab the headlines and not so much to identify any problem. The solution to that is November 5th.

I also believe those 4 words were used in a Paul Newman movie ~ Cool Hand Luke. 

There is yet another aspect in the assumptions we individually make and then ask for something based on a not so clear assumed condition. I received another email last week that simply said send me the code.  I wrote back that unless the person identified the specific project I was at a loss as to what to send as it was a failure to communicate. I have not heard back. 

Without making an issue, the several requests for send me the unidentified code came from offshore where English is not the primary language. So that may be a factor but that is not an excuse!

The new phrase might be: If You Want Stuff You Have To Know Stuff. The knowing may be as simple as identifying specifically what you want. 


Rated #1 on Sherwood Engineering's list


This raises a question (back on to the Techie Stuff). The question of the day involves gain distribution in a homebrew receiver and where should the gain stages be applied. This borders on how big is big? 

But as we well know everyone wants a specific number if only to argue -- that is too big or too small. For the one or two sharp shooters in the blog readers set, your ears should perk up as you ready an argumentative response. 

There are neat terms like MDS (minimum discernable signal) where you can quantify that a particular topology can copy a weak signal with the weakest identified as MDS. 

Too much gain at certain parts of the signal train can cause a lot of noise to be amplified and carried along with the signal. This is especially true in front end RF Amplifier stages. Several commercial designs simply have no RF amplifier stages. This tends to work well below 20M but when you get beyond 17M -- the receiver almost sounds like it is on life support. No Noise BUT No Signals.

So, by picking a reasonable level of RF amplification walks the thin line of boosting the incoming signal without overly boosting the noise. A gain of say 5 to 10dB for the RF Amp would be a starting place. 

But external noise is not the only noise as there is noise internally generated within the receiver itself. This drives what you use and how you use it. Running stages Class A would likely result in a different outcome than from those running in other classes of operation.

Analog Devices has an exhaustive paper on noise in a receiver and can be seen here

Intermediate stage gain must consider that you want to assure you are not hitting the Crystal Filter with a sledgehammer. W7ZOI has often used a Pad after the post mixer amplifier so you are not really banging the crystal filter with signal. It also helps if you limit the bandwidth of the signals being applied to the filter especially those coming from the Balanced Modulator in a transmitter configuration.

A chance to make up for signal deficit lies with the audio amp stage. Not any old stage like a LM386, but a well-designed stage that delivers a significant amount of stage gain without a lot of noise in the side car is the goal. A homebrew audio amp using multiple gain stages is certainly a choice. 

So, what is a number for overall stage gain? Such a number is a trap unless you also consider a clean sound coming out of the speaker. To hedge my answer the overall stage gain should be that required to copy weak signals while minimizing internal and external noise at the band of operation. Old wives' tales often suggested 100dB.

TYGNYBNT. Don't eat your pet.

73's
Pete N6QW

Ham Radio Tech: Choosing a Portable Vertical Antenna that Matches Your Needs

Whether you’re a seasoned ham or buying your first antenna, choosing the right one is more about how you operate as an individual and less about the antenna’s capabilities. In previous OnAllBands articles, I’ve explored field antennas and the decision-making process behind choosing the right one. I believe that a practical understanding of your operating style is key to making the best choice.

This article is about vertical antennas—specifically, those designed to be portable and stealthy. These antennas are ideal for field operations like POTA, SOTA, or IOTA, and for those living under HOA restrictions that prohibit permanent antennas.

portable ham antenna set up on mountainside
(Image/Thomas Witherspoon, K4SWL)

There are hundreds of vertical antennas on the market, and it’s beyond the scope of this post to cover them all. Instead, I’ll focus on three models I’ve personally used, each representing different concepts and reasons why you might choose one over another.

All of these antennas are multi-band, and while some can be installed permanently with proper sealing, they are primarily designed with portability and ease of setup in mind.

Before diving into the specifics, consider these questions as you search for your next antenna:

  1. What modes and power levels do you intend to operate? Ensure your antenna can handle the wattage and duty cycle of your chosen mode (SSB, CW, Digital). For example, an antenna that handles 100 watts SSB may not be suitable for 100 watts FT8.
  2. What bands do you plan to operate? Confirm that the antenna covers your preferred bands. Portable verticals are effective on 20 meters and above but become less efficient at lower frequencies due to the need for loading coils to electrically lengthen the radiating element. This compromises performance and decreases operating bandwidth. However, I’ve had great success on 80 meters with some portable verticals, though they are less efficient compared to longer wire antennas.
  3. How far do you plan to hike with this antenna? Check the specifications for weight and element lengths, as these factors will impact your comfort and the feasibility of carrying it in your pack.
  4. How important is frequency agility? If you primarily operate FT8 and stay on one frequency for extended periods, any antenna will likely suffice. If you frequently move across bands to chase activators or DX, consider an antenna that doesn’t require manual tuning.

***

Three Types of Portable Verticals

Here are three vertical antennas I’ve used in the field, along with their pros and cons:

***

1. Quarter Wave Verticals

One of the simplest vertical antennas is the quarter wave. My first quarter wave antenna was a 5-meter radiator wire (one-quarter the length of 20 meters) with four counterpoise wires on the ground. I attached the radiator to the center of my coax and the counterpoises to the shield. I’ve deployed the radiator vertically in a tree (great for permanent setups) and supported it with a fiberglass telescoping fishing pole (ideal for portable use).

While these antennas are simple to build, I prefer an antenna that works on multiple bands and is easy to deploy and pack. This is why I’m a big fan of the Chelegance MC-750 .

portable ham antenna set up near riverbank
Chelegance MC-750 Portable HF Vertical Antenna (Image/Thomas Witherspoon, K4SWL)

The MC-750 is a portable vertical deployed using either a stainless ground spike or a tripod. The vertical element is a stainless steel whip with silk-screen markings that help you deploy the antenna for resonance on multiple bands.

close up of a telescoping radio antenna joint
(Image/Thomas Witherspoon, K4SWL)

When I follow the silk-screen markings and all four counterpoise wires (attached to the base), I consistently achieve a near 1:1 SWR. Thus, no ATU is needed. The SWR remains consistent across various topographies.

radial wires and RF connector on a portable antenna
The Chelegance MC-750 comes with jacks to install four included preassembled counterpoise radials. (Image/Thomas Witherspoon, K4SWL)
portable ham radio antenna in bag
Chelegance MC-750 carrying case (Image/Thomas Witherspoon, K4SWL)

The MC-750 ships with a coil for 40 meters. Chelegance also offers an optional 80 meter coil as well.

  • Pros: Easy deployment, high quality, efficient, multi-band use with no ATU needed, resonates on 20-10 meters and 40/80 meters with coils, comes with a custom padded carrying case. 
  • Cons: Not truly a con, but you must adjust the whip length when changing bands if not using an ATU.

***

2. Verticals with Transformers

portable ham radio antenna set up in a field
Chameleon CHA MPAS Lite Modular Portable Antenna (Image/Thomas Witherspoon, K4SWL)

If you regularly use an antenna tuner in the field, you might prefer a high-quality multi-band vertical antenna equipped with a transformer to reduce potentially high impedances to a level manageable by most tuners. I think of this type of antenna as the vertical equivalent of a random wire antenna. Many of my QRP transceivers have internal ATUs, making this type of antenna very appealing. The one I have the most experience with is the Chameleon CHA MPAS Lite.

Like the MC-750, the MPAS Lite uses a stainless steel whip but includes a transformer at the base, making it easier to match the antenna across multiple bands with virtually any ATU. Additionally, it can operate on lower bands, including 80 meters, without needing a loading coil attached. While not as efficient below 30 meters, it remains highly effective for both POTA and SOTA where you are often the DX.

portable ham radio antenna set up over mountain range
(Image/Thomas Witherspoon, K4SWL)
portable ham radio mounted to a picnic table
(Image/Thomas Witherspoon, K4SWL)

The MPAS Lite offers excellent frequency agility, which is a major advantage if you frequently hunt or chase other stations in the field. Just change the frequency, activate the ATU, and you’re set.

close up of ham radio antenna base on table
(Image/Thomas Witherspoon, K4SWL)

The MPAS antenna can also be configured as an end-fed random wire using the counterpoise wire. Consult the MPAS Lite manual for multiple configurations.

  • Pros: Easy deployment, high quality, multi-band use, frequency agility, only one counterpoise, versatile platform for multiple antenna configurations. 
  • Cons: Pricier than the MC-750.

***

3. Loading Coil Verticals

I’ve used several antennas with helically wound coils and a sliding tuning coupler at the base to match the antenna across multiple bands. The coil at the base shortens the antenna electrically, making it portable and low profile—ideal for stealthy use or in neighborhoods with aggressive HOA restrictions.

Among the many coil antennas available, the new REZ Antenna Systems Ranger 80 stands out for its robustness. I was impressed with its ease of setup, high quality, and smooth tuning coupler. The REZ Ranger 80 antenna also handles higher power than other coil systems—100 watts CW/digital and 200 watts SSB.

ham radio antenna installed near a forest
REZ Antenna Systems Ranger 80 HF Portable Antenna System (Image/Thomas Witherspoon, K4SWL)
Radio wires plugged into an antenna base
(Image/Thomas Witherspoon, K4SWL)

The Ranger 80 is quick to deploy and incredibly durable. While I’ve never been a big fan of verticals with loading coils and sliding tuning couplers, as they can be finicky to tune, I found the REZ Ranger 80 to be the best of the bunch and more forgiving than others I’ve used.

base loading coil for a ham radio antenna
(Image/Thomas Witherspoon, K4SWL)
  • Pros: Easy deployment, superb quality, higher power handling capacity, multi-band resonance, no ATU required. 
  • Cons: Heavier than other options, tuning coupler needs adjustment for each band change, pricey.

***

Summary

Choosing the right portable vertical antenna is more about matching your equipment to your specific operating style than simply selecting the most capable model. Whether you prioritize ease of deployment, frequency agility, or power handling, the antennas discussed—like the Chelegance MC-750, Chameleon CHA MPAS Lite, and the REZ Ranger 80—offer distinct advantages that cater to different needs.

Before making your decision, consider the nature of your operations. Are you regularly chasing signals across multiple bands, or do you prefer to set up and stay on one frequency? Do you need a lightweight, portable solution for long hikes, or are you more concerned with stealth and ease of use in restricted environments? Your answers will guide you to the right antenna.

Ultimately, the best antenna is the one that enhances your enjoyment of the hobby, allowing you to operate confidently and efficiently in your chosen environment. If possible, try before you buy—borrowing from friends or club members can provide valuable insights that specs alone can’t offer.

The post Ham Radio Tech: Choosing a Portable Vertical Antenna that Matches Your Needs appeared first on OnAllBands.

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