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).
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 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.
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→
Many thanks to Barry (KU3X) for sharing the following guest post originally posted on his website:
Product Review: PAC-12 Portable Multi Band Vertical Antenna
by Barry G. Kery, KU3X
I am always on the hunt for a better mouse trap. Dave, NB3R came across a great multi band vertical antenna for portable operating. It’s a, “ PAC-12 7-50MHz Shortwave Antenna “ found on AliExpress.com.
The PAC-12 antenna is designed to operate on any frequency from 6 meters down to 40 meters.
Numerous manufactures make multi band vertical antennas designed to be used for portable operating. Some have quality issues and others may have performance issues, or both? Any hunk of wire or aluminum will radiate if RF is applied to it, but how much will be radiated is the question.
When it comes to ground mounted vertical antennas, one major factor that effects performance is the ground radial field. The PAC-12 comes with a long ribbon cable that you will have to separate each wire and cut to a quarter wave length per band of operation. There are ten wires within the ribbon cable. The length of the ribbon cable is 18 feet. This is too short for 40 meters but perfect for 20 meters. I made four 35 foot long radials out of some wire I had laying around the shack. This will increase the performance on the 40 meter band as well as making a better match. Spread the radial wires out equally around the base of the antenna. Since the radials are not elevated, they do not have to be tuned but it does make for a better match.
The antenna comes with a short stake that can be driven into the ground for attaching the ground radial crimp on to and attaching the feed insulator.
The stake is strong enough to support the entire antenna, even on windy days. The feed insulator has an SO-239 for connecting your coax. The feed insulator must be attached to the ground stake correctly. Make sure the writing on the insulator is on top of the SO-239 and the black portion of the insulator is attached to the ground stake.
So what makes this antenna perform better than most other commercially made portable vertical antennas? Answer, “the mast!”
Most manufactures, not all, use a tapped base loading coil to make the antenna resonant on numerous bands. On a quarter wave antenna, the wire or aluminum closest to the feed point of the antenna is the current portion of the antenna and the current portion does the most radiating. Continue reading Barry reviews the PAC-12 portable antenna→
Do you usually try to use an isolator or do you often let your wires touch branches by just pulling them over? When you deploy 20m EFHWs, for example, do you try to avoid having an end touch a branch and only have the throw line going over the branch? I tried to go through your videos and look but you don’t often mention how far you pull the wire up and possibly over. Thanks!
This is a great question!
Before I answer, I’d like to add a little context:
I am a QRP operator. The maximum amount of power I use in the field is 10 watts, but 99.5% of the time, it’s actually 5 watts or even much less.
I am answering this as a field operator, meaning I’ll be referring to temporaryantenna deployments.
That said, the quick answer is no, during park and summit activations, I do not worry about my antenna radiator wire touching tree branches.
I do isolate the end of my wire antennas from tree branches and leaves, but I don’t worry about other parts of the radiator touching.
Also, all of my antenna wire has some sort of jacket–I don’t run bare wire in the field.
Many thanks to Dale (N3HXZ) who shares the following guest post:
Does your antenna counterpoise orientation matter?
by Dale (N3HXZ)
I am an avid SOTA and POTA activator and love field operation. I use a portable vertical whip antenna with a single counterpoise for my antenna system and have always wondered if orienting my counterpoise would provide some signal strength gain in a particular direction. I decided to run a series of tests using WSPR to gather field data, and use statistics to answer the question:
Does one counterpoise orientation favor another in terms of average signal strength?
WSPR is a great tool for antenna testing. You can study various antenna configurations by making some WSPR transmissions and then checking the data on the WSPRnet database to see how well the signal was received at various stations located all over the world. You have to be careful in interpreting WSPR data though as receiving stations have different antenna and radio configurations, and the band propagation can vary rapidly at times. So how do you take advantage of all the data you receive from stations and draw some meaningful conclusions? I have found that using proven statistical theory in analyzing the transmitted signal strength received from individual stations can provide you results that you can confidently trust.
So what statistical algorithm is helpful?
For antenna signal strength comparison between two configurations, you can use an independent two-sample t-test with a one-tailed t-test evaluation. It sounds like a mouth-full, but it is quite simple. For our purposes, the t-test compares the average signal strength at a given receiving station from two different antenna configurations. The one-tailed test validates or invalidates the hypothesis that one antenna configuration produces an average signal strength greater or less than the other antenna configuration.
The testing requires that you run WSPR long enough to gather multiple reports at a single receiving station for both antenna configurations. Using the signal strength reports, you compute the average signal strength and the standard deviation of the signal strength over the sampled data points. Excel can easily provide that data. With this information and the number of sample points for each antenna configuration (they can be different), you then run a calculation by hand or in Excel to compute the ‘t’ value.
This ‘t’ value is then compared to a critical value for the number of sampling points from a ‘Students t table”. If the ‘t’ value is less than the critical value you can confidently conclude that the hypothesis is false and therefore conclude that there is no significant difference in the mean value of the signal strengths between the two. If the ‘t’ value is greater than the critical value you can accept the hypotheses that one antenna configuration produces a greater or less average signal strength than the other configuration. Continue reading Dale uses WSPR to test counterpoise orientation→
Thomas, thanks for all of your activation videos related to the Elecraft AX1 antenna. I ordered one the day you announced the package deal, and it arrived in less than a week. I’ve activated a few parks with it already (20m SSB). Like you and many others, I’m impressed.
About a year ago, a friend (NG4S) loaned me his pair of WSPR transmitters and suggested that I explore building and comparing antennas. I’ve been hooked on antennas of all kinds and WSPR since then.
I began doing WSPR tests on the AX1 the day after it arrived. With two transmitters set to the same frequency and power output, you can do direct comparisons between two antennas under identical propagation conditions.
I’ve already done a couple of comparisons between the AX1 and other commercial antennas. But I think the test I just completed might be of particular interest because it pits the AX1 against an antenna I’ve seen you use many times – a 28.5’ end fed with a 28.5’ counterpoise. I used 24 AWG silicone insulated wire. The end of the radiator was placed on a 19’5” telescoping fishing pole. This is my preferred POTA mast when I can’t use a tall tree.
I spent some time trying to control other variables so that the only significant difference during the test would be the antennas themselves.
For example, the SOTA Beam WSPRLite Classic transmitters don’t have an ATU. So, I had to make the antennas resonant on the 20-meter WSPR frequency of 14.097 MHz. For the AX1, Thomas’ videos helped a lot. I used a clip-on capacitance hat and adjusted the counterpoise to 15’ 2”. This gave me an SWR of 1.17:1. For the end fed, I tried the two UNUN’s I had available and settled on the 49:1, which got me the closest (2.2:1). I then used a manual tuner to achieve an SWR of 1.29:1.
I also wanted to deal with the difference in power output between the two transmitters. Although they’re identical, and both set to 20 milliwatts, there is no way to ensure both are actually producing that output level. Based on tests by NG4S, one of the transmitters runs at 19 milliwatts. The other actually outputs 27 milliwatts. So, my plan was to run the test for 48 hours. At the end of 24 hours, I would switch the transmitters (and callsigns) so that both antennas would benefit (relatively equally) from one of the transmitters being stronger.
At the end of Day 1, I reviewed the data from the two transmitters on dxplorer.net/wspr. The end fed averaged a 5.7 dB gain over the AX1 based on reports from receiving stations that spotted both transmitters in the same 10-minute block (simultaneous spots).
On Day 1, the stronger transmitter was on the end fed. The maps below are from WSPR.rocks.
How I found the best antenna for my SOTA/POTA activations
by Thomas (DM1TBE)
Until January this year I had a German “Klasse E” / CEPT-novice amateur radio license (equivalent to the US General Class), which limits the use of HF to the 10-,15-, 80- and 160-meter bands. When I started with SOTA I used homemade single band end-fed antennas most of the time. However, that is only feasible for the 10- and 15-meter bands.
Unfortunately, both bands are very moody and sometimes they have not worked at all. Unlike the UK for example, FM is uncommon for SOTA in my home association DM (i.e. Germany Low Mountains). You can be lucky and get your 4 QSOs, but I did not want to rely on pure luck.
Therefore, I bought an end-fed half-wave antenna for 10-, 15-, 20-, 40- and 80-meter bands, after some experiments with 10-80-meter end-fed half-wave antennas, from a small German company called ANjo.
Although I could not use the 20- and 40- meter bands at that time, the EFW80-10P (en: auto-translated) antenna gave me the possibility to use the 80-meter band. The antenna could also be tuned for 15. It has a mechanical length of 23.6 m / 77 ft and a coil for the 80-meter band. It is pretty lightweight with 0.4 kg / 14 oz and allows up to 30 watts PEP – more than enough for me. 80-meters is not the best band for daytime SOTA activations, but in 21 months doing SOTA activations, it worked 37 times and tipped the scales for an activation from time to time.
It was sometimes a bit tricky to raise the long wire into the air, but it always worked … better or worse …somehow … like here in the woods along a trail.
Many thanks to Skip (K4EAK) who shares the following guest post:
The QRPguys DS-1 Portable Antenna Kit
by Skip (K4EAK)
There have been several videos and extended comments lately about the Elecraft AX1 and AX2 antennas, both of which function remarkably well for a small, highly compromised antenna.
For those interested in other, similar designs, especially those hams who find that building the equipment is half the fun, another option to consider is the QRPguys DS-1 antenna.
The DS-1 is similar in concept and design to the AX2. It consists of a base-loading coil, a 46.5-inch collapsible whip, and a plate to attach the antenna to a small tripod. One can also purchase an add-on 40-meter coil. The can be deployed in just a couple minutes and, when collapsed, the longest portion is only 6.5” long, easily fitting in the palm of one’s hand. QRPguys recommends a 16.5′ counterpoise; I use two such wires, usually spread out at a 180-degree angle. I’ve also used it with a clamp-on mount and a car window mount.
Building the antenna is simple and took me less than an hour. After installing a BNC connector into a brass plug and inserting the plug onto a length of PEX tubing, one simply runs the supplied 22AWG wire from inside the tubing, out and around making 22 turns, and then sealing it with a length of heat shrink tubing.
There are really only two aspects of assembly that are slightly more difficult. The first is that it’s necessary to drill and tap two holes for 4-40 screws, which obviously means that (1) one needs a 4-40 tap and (2) one needs to be careful tapping the threads to assure a clean cut. The second is that the heat shrink tubing, at least as supplied in my kit, was grossly oversized, which required some finesse in getting a final product that was at least reasonably aesthetic, to say nothing of accomplishing that without dry roasting my fingertips.
Field testing of the DS-1 shows that it works surprisingly well. The SWR is well below 2.0 across almost all of the 20-meter band and where it is higher than that (the upper end of the voice portion), the KX2 internal tuner can tune it easily. As one would expect, on 40 meters the antenna has a somewhat narrower range, although the KX2 tuner has handled it on all of the frequencies I’ve tested so far (all CW). And it appears to be efficient enough.
I have used it on numerous activations and consistently get to the requisite 10 contacts within 20 minutes or so after getting spotted. After that, the number of contacts depends on the time available, but for those occasions when I have only a 30-minute window for an activation, the antenna is a convenient and practical alternative.
I keep the antenna, the tabletop tripod, and the counterpoise wires in the water bottle pocket of my pack, ready for use whenever I have a few moments for a quick activation.
(This article is full of educational and fun links – click on as many as you wish)
Antenna tuning on Superb Owl Sunday
by Vince (VE6LK)
While many in North America were watching a number of Superb Owls move a pigskin around a playing field, I was off to play radio, successfully, for the first time in weeks. This is part of my goal to activate 200 CW POTA contacts per month this year.
During recent visit to Vancouver attempting to operate from within my hotel room, and utilizing the Edisonian Approach, I was shown -more than once- what did not work. This will no doubt be a discussion point on an upcoming Ham Radio Workbench Podcast. I was therefore in very bad need to get back on the air while operating portable. I was close to feeling twitchy and in need of some POTAXXIA (Hyperradio Moduzolium). A plan was needed!
Chain Lakes Provincial Park (VE-1168) is located between the Porcupine Hills and the Rockies on Highway 22 (locally known as the Cowboy Trail) in Southern Alberta, about 90 minutes south of Calgary. It’s especially gorgeous at sunrise and sunsets. A campground, lake with boat launch and a day use area all adorn this park created for water management with an earthen dam. While it is in a valley, the wind can be howling on some days. On this day it would prove to be just above a nuisance, sort of like mosquitos in the spring -you can live with the nuisance, but only for so long before you blow a proverbial gasket.
I located a lovely spot below the dam -and the majority of the wind- however it was outside of cellular range. I’d need to rely on the Reverse Beacon Network to spot me. The RBN will, in turn, post your spot to the POTA website once it hears you if you schedule your activation in advance.
The place I found would only be more perfect were it warmer than 45F and without wind. A babbling brook was by the picnic table, and a nearby footbridge had built-in supports for my painter’s pole that would serve as the far end support. I’m pretty sure that they weren’t intended for me specifically, but they were the perfect size to simply slide the pole into place and hold it firmly. By luck I parked the truck the correct distance away with it’s drive-on mount and 28′ Fibreglass Flagpole from Flagpoles-To-Go via Amazon. Continue reading VE6LK: Antenna tuning on Superb Owl Sunday→
Product Review: Chelegance MC-750 Portable Ground Plane Antenna, Part 1
by Charles Ahlgren, KW6G
I recently purchased a Chelegance MC-750 portable ground plane antenna from DX Engineering. Essentially, the antenna system provides a ¼ wave portable vertical antenna with 4 counterpoise wires that operates on 20 through 10 meters. The antenna will also operate on 40 meters with the provided loading coil. The manual states the antenna will support 6 meter operation, but no instructions are provided on how to do so. 30 meter operation is not supported. It appears from our initial testing that no ATU is required.
Here are some of my thoughts on the antenna.
The MC-750 comes with the following components:
GROUND ROD / ANT BASE
50 CM ANT ARM
5.2 M WHIP
7 MHZ COIL
4 COUNTERPOISE WIRES (radials)
COUNTERPOISE WIRE COLLECTOR BOARD
As provided, it is designed to operate on the 40, 20, 17, 15, 12, and 10 meter bands without any modifications. Six meters is also supported per the manufacturers manual, but no guidance on how to do that is offered in that document. However, finding the proper length of radiator for 6 meters should be straightforward using a tape measure to set the proper whip length.
[Update: Chelegance notes that to operate 6 meters, simply extend the last segment only of the whip (see photo) and for 30 meters extend the last four segments of the whip and 15cm on the 5th segment (see photo).]
I checked the ground rod / antenna base with a magnet and confirmed it is made from stainless steel as both components are not magnetic; a characteristic of stainless. Both the ground rod/ antenna base and the 50 cm antenna arm (which was also non-magnetic) had a hefty feel (together, they weigh about 2 pounds), therefore I think it safe to assume that these components are made of stainless steel. Since most ops will undoubtedly use the antenna arm as an aid to inserting / extracting the ground rod into / from the ground, it seems a prudent decision by the manufacturer to have this piece fabricated from a strong, stiff material such as steel. The machine work used to fabricate these parts appears to be quite good – the fit and feel were excellent, with no sharp or ragged edges to cause problems in the field.
I measured the whip while set at the various position marks for 20 through 10 meters. The band markings on the whip were accurate – giving a 1/4 wavelength radiator when combined with the 50 CM ant arm length…On 40 meters, the whip and rod measured about 1/8 wavelength. The required the loading coil needs to be inserted between the whip and the rod (at approximately 1/10 the total 40 meter whip height above the base). If you want to operate this antenna on 30 meters, it appears that you need to provide an extra 1.4 meter of additional rod as a quarter wavelength ground plane at 10.1 MHz requires a 7.1 meter radiator. Six meter operation would require a whip of around 4.7 feet. With the whip fully collapsed, the length of the rod and antenna arm measures 40-1/4”. Therefore, if 6 meter operation is contemplated, extending the whip about 16 inches from fully collapsed should suffice. However, I don’t think that an antenna configuration such as that would be a very good performer unless it were elevated from ground level; or maybe it would be good for a SOTA activation? Continue reading Guest Post: Reviewing the Chelegance MC-750 (Part 1)→