Raddy RF75A Shortwave Radio

Since I purchased the Raddy RF750 Portable Multimedia Player a year ago, it has become my favorite portable receiver. So, when the folks at Radioddity asked me if I’d like to have a look at a new upgraded version, I jumped on it. The new radio is the Radioddity RF75A Shortwave Radio, and it includes some interesting new features.

[Disclaimer: In the interest of full disclosure, Radioddity sent this radio to me free of charge to evaluate and review. However, the opinions expressed here are entirely my own and were not influenced by the vendor.]

What It’s All About?

Like its predecessor, the RF75A is a multimedia device. It covers the AM, FM, Shortwave, Weather, and VHF bands. In addition, you can play audio files from a micro SD card. In Bluetooth mode, it’ll play audio from an external source. You can also connect a computer to the USB connector and use the RF75A as a speaker.

Some specs from the Raddy Website include:

FM: 64-108MHZ (Step Value: US: 10KHZ, EU: 9KHZ)
AM: 520 -1710 KHz
SW: 4.75 – 21.85 MHz
WB: 162.400 – 162.550 MHz
VHF: 30 – 199.975 MHz
TF Card Max Capacity: Max 256GB
Audio Format: MP3, WAV, WMA
Size/Weight: 3.6’’ x 2’’ x 1” / 3.7 oz
Components & Accessories: 1 x RF75A, 1 x Storage bag, 1 x Lanyard, 1 x Wire antenna, 1 x Type-C cable, 1 x Earphone

The internal 1000mAh battery is charged via a USB-C connector, which is handy for a portable radio. The RF75A also has a built-in flashlight and an “SOS” mode. In the SOS mode, the flashlight flashes and the radio emits an ear-piercing siren. 

At the time this post was written, the RF75A was selling on the Radioddity website for $52.99 (USD).

The Raddy RF75A from Radioddity
The Raddy RF75A from Radioddity

Major Improvements in the RF75A

While the basic functions of the RF75A and RF750 are similar, there are some big changes in the RF75A. The first thing you’ll notice is the digital display and digital tuning. I found the analog tuning on the RF750 a little touchy and the frequencies hard to read. The RF75A’s digital tuning makes tuning much easier. 

One interesting improvement in the RF75A is an app that lets you control the radio from your smartphone over a Bluetooth connection. While the RF75A is pretty simple to operate as it is, the app makes it even easier.

Screenshot of the RF75A Android app, which allows you to control the radio from your smartphone.
Screenshot of the RF75A Android app, which allows you to control the radio from your smartphone.

My Impressions

The first thing that struck me is the RF75A’s small size. It’s smaller than an Altoids tin and thinner than the RF750, so it’ll easily fit in your pocket. 

The Raddy RF75A (left) compared to the RF750. Besides the digital display and controls, the RF75A has a slimmer profile making it more "pocket friendly."
The Raddy RF75A (left) compared to the RF750. Besides the digital display and controls, the RF75A has a slimmer profile making it more “pocket friendly.”

Like the earlier radio, the sound quality is impressive. Listening to the FM band, the sound through the speaker has a rich sound you wouldn’t expect from such a small radio. The supplied earbuds are comfortable and also sound great to these old ears. The RF75A seems to have a little less bass than the RF750, but the sound is still very good.

I found the reception on the AM broadcast band to be very good, easily pulling in local stations. Because of high noise levels, my home location isn’t the best place for testing the shortwave bands. However, using the scan function, I was able to find several shortwave stations. I should note that the RF75A only receives in AM on the shortwave bands. So, if you want to listen to SSB or CW signals, you’ll have to look elsewhere. It comes with an antenna wire (approximately 10 feet long) that you can clip onto the built-in antenna to improve reception.

On the VHF band, I programmed in some local 2M repeaters and a few public service frequencies to test it out. Using the buttons on the radio, I found the tuning steps too coarse to zero in on some frequencies. Using the app, however, it was a simple task to enter the frequencies and save them as presets. Reception was good, but there’s no squelch setting. So, you’ll hear some background noise between transmissions. 

The memory card function works great and gives you a choice of four different play modes. I set it to play my MP3 files in random order. You can also choose from six different EQ settings. Using the RF75A’s Bluetooth mode, I was able to pair it to my cell phone and play audio files that way.

I also tested the alarm function. I like having the option to have the radio turn on instead of sounding an alarm. The alarm sound is a loud series of beeps, so I’d rather wake up to music. 

The smartphone app is easy to install and makes it easy to operate the radio (especially for my old eyes). The Android version of the app, however, requires the manual download and installation of a .apk file. I would feel safer getting the app through the Google Play store, instead of downloading it from an unfamiliar website. Apple iPhone users, however, can get the app from the Apple app store. 

Once installed, the app requires access to your phone’s location in order to pair with the RF75A. I’m not sure why the Bluetooth pairing depends on location. In any event, I only allow access to the phone’s location when I’m actually using the app, and I close the app when I’m not using it.

While the Operational Guidelines booklet provided with the radio is sufficient to get you up and running, it’s not without some issues. The wording is confusing in some places, and I came across a few errors and formatting issues. Despite these editorial shortcomings, I had no problems figuring out how to use the radio. 

The Radioddity website claims 7-8 hours of use from the 1000mAh battery. I haven’t actually measured it, but that seems about right. The USB-C charging port is handy, too. I can charge it using my cellphone charger or a portable power bank when I’m camping.

The last function I evaluated was one of the more important features for me: the weather alert function. To test it out, I set up the RF75A in the “Alert” mode in time for the weekly NOAA Weather Radio test. The alarm went off as expected, and boy, did it ever go off! Like the RF750, the weather alert triggers an extremely loud siren. Along with the siren, the light on top of the RF75A flashes, just like the SOS mode. I really wish there was the option to just activate the weather radio in response to an alert. Or, at the very least, be able to adjust the volume of the siren. As it is, I can’t imagine using it in a campground at night.

The Bottom Line (for me, at least)

All in all, I really like this little radio. It’s small in size, weighs next to nothing, and sounds great. I like that it’s simple to operate without having to navigate through a bunch of menu options. The smartphone app is a terrific improvement that further simplifies things.

Since I received it, the RF75A has seen a lot of use around the house, and I plan to take it along on camping trips and travel. Now, if there was only a way to tone down that weather alert, I’d be a very happy camper. 

73, Craig WB3GCK

Samurai Tactical Wakizashi Backpack

Over the past couple of years, some knee issues have slowed me down. My new knee joint resolved those issues, and life is getting back to normal—as normal as my life gets, I suppose. Anyway, I’m planning to get back to doing some light hiking this year as the weather improves. With that in mind, I bought a new backpack to use on day hikes.

For the past four years, I have been using the Rambler sling pack from Red Rock. It has been—and still is—a great backpack. It has plenty of storage for hauling a radio and accessories out to the field, and it is one sturdy, well-built pack. My only issue with it is that it is a sling pack. For short trips, it’s fine. But, for longer trips, having all the weight on one shoulder feels a bit “lopsided” to me. If I could have the same pack with two shoulder straps, I would be a happy camper (hiker).

A while back, I came across the Wakizashi backpack from Samurai Tactical and saved it to my Amazon wishlist. The Wakizashi is similar in size to my Rambler sling pack. While it has fewer storage pockets than my sling pack, it has more than enough storage for my needs. (I tend to carry too much stuff with me anyway.) 

When I purchased it, the Wakizashi backpack in black was selling for a mere $24 (USD). (Other colors are available at slightly higher prices.) For that price, if I didn’t like it, I could always give it to one of the grand-kids. The average ratings were 4.6 out of 5, so I took a chance and placed an order.

I should also note that I have no financial interest here; I paid for the backpack with my own funds. Also, the Amazon link above is not an affiliate link.

Amazon delivered the pack to a neighbor’s porch a few days later. I had to wander the neighborhood in the rain to find it. Not cool, Amazon. 

I wasn’t expecting much for a $24 backpack, but I was pleasantly surprised. For a cheap backpack, it seems well built. A few of the many reviews complained of poor stitching and general issues with quality. I saw none of that in the item I received. Mine was well-built, and the material appears to be durable enough. 

Samurai Wakizashi backpack. The patches and HT pouch were added by me.
Samurai Tactical Wakizashi backpack. The patches and HT pouch were added by me.

The pack measures 17.1 x 11.1 x 6.1 inches with a capacity of 24 liters. There’s a large main compartment and a smaller admin compartment. There are also two smaller compartments near the top of the pack. A side pouch is large enough for a water bottle, and there is plenty of MOLLE webbing on the sides and back. If you’re so inclined, it accommodates a hydration bladder and has a hydration port at the top of the bag.

Samurai Wakizashi backpack shoulder and sternum straps.
Samurai Wakizashi backpack shoulder and sternum straps.

Although the Wakizashi backpack has fewer compartments than my sling pack, there is enough storage to accommodate everything I normally carry in the field. Besides the radio gear, I always carry a small first aid kit, emergency poncho, headlamp, and a few other emergency items. The main compartment is a bit larger, so things that present a tight squeeze in the sling pack fit easily in the Wakizashi. 

I’ve been using this pack for the past couple of months now with no issues. How well it holds up in the long term remains to be seen. For now, anyway, I’m happy with this budget backpack.

73, Craig WB3GCK

She Knows Me So Well

Among the Christmas gifts my XYL gave me was one that sums me up perfectly. She understands my love of coffee, and she is very supportive of my ham radio hobby. With this sweatshirt, I can proudly display both of my addictions.

One of the Christmas gifts I received from my XYL. It suits me perfectly!
One of the Christmas gifts I received from my XYL. It suits me perfectly!

I don’t have a link to the source, but my XYL says she found it on Amazon.

Happy Holidays!

73, Craig WB3GCK

Evolve III Maestro E-Book

You’ve most likely heard hams talking about the Evolve III laptop over the past few months. I had been hearing about these little laptops being snapped up at prices as low as $60. Several ARES-RACES colleagues have been happy with them, and there’s even one running 24 x 7 as a VARA FM digipeater in our Emergency Operations Center. So, I had to buy one and judge for myself.

So, what is attracting hams to this laptop? Of course the low price is attractive to frugal hams. It’s also small (11.6-inch display) and light, making it useful for portable operation. Speaking of portable operations, you can charge the Evolve III from a 12-volt DC source. Out in the field, you can charge this laptop from the same type of 12-volt battery used to power your rig. 

Evolve III Maestro E-Book
Evolve III Maestro E-Book

Despite its low cost and small size, it’s a capable little machine. It runs the Windows 10 Pro Education operating system, and has two USB ports and a micro SD memory card slot. A 1.1 GHz Celeron processor runs the laptop, and it has 4 GB of RAM and 64 GB of data storage. 

Micro Center stores have been selling them for $59.99 with a limit of five per customer. When I checked my local store, they were out of stock, so I bought one on Amazon for about $89. (Still a bargain, I think.) These laptops are obviously clearance items, since the Evolve website shows newer models running Window 11.

My plan for this little laptop is to use it for logging during QRP-portable operations, especially Field Day and Winter Field Day. I also want to use it for digital communications during ARES-RACES exercises and deployments. 

Getting started with the Evolve III was the same as any other Windows 10 device I’ve owned. The initial Windows setup didn’t take long, and I was ready to install some software. I started by installing the software I use for logging, e.g., N3FJP ACLog, SKCC logger, HamRS, N3FJP Field Day Logger, etc. Everything ran without issues. 

Next I installed the software I need for ARES-RACES. First up was Winlink Express, along with VaraFM and SoundModem. Then, I installed the Narrowband Emergency Messaging System (NBEMS) software, i.e., fldigi, flmsg, and flamp. Over the past two weeks, I’ve been making solid connections to a local Winlink node on 2M using VARA FM. The NBEMS software has also been working great during our local ARES-RACES digital nets.

After using the Evolve III daily for the past few weeks, I really like it. The keyboard has a good feel to it, and the display looks good. I used it outdoors in the shade and the display was still readable. You might need to crank up the brightness, though. 

Is it the fastest laptop? No way. Is it fast enough? Absolutely. I’ve heard of hams running FT8 on these things with no issues. You would think the 64GB of storage would be a limitation. However, after installing the ham radio applications I use, I still had about 24GB left. Just in case, I took advantage of the Micro SD card slot and added an extra 128 GB of storage.

I’m really impressed with the battery life. Depending on what I’m doing, I get more than eight hours of operation on a charge. 

Lately, it seems like my house is where computers go to die. I’ve had a laptop and a desktop go belly-up in recent months. Given what I paid for the Evolve III, if it dies, I won’t feel a tremendous loss. 

73, Craig WB3GCK

Giving My Rig the Royal Treatment

Over the years I have accumulated a stash of the bags that Crown Royal whiskey comes in. I don’t drink much hard liquor myself, but I have a relative who enjoys a nip now and then. She knows I have a thing for bags and containers, so she passes them along to me. I graciously accept them, figuring someday I’ll find a good use for them. 

When I take my Penntek TR-35 on the road, I use a repurposed insulated lunch box to carry the radio, an Elecraft T1 tuner, along with a variety of accessories. Pending a better solution to protect the TR-35 from bouncing around, I wrap some bubble wrap around it before placing it in the box.  Decidedly low-tech, but effective.

The Crown Royal bag, along with my TR-35 transceiver
The Crown Royal bag, along with my TR-35 transceiver

The lunch box works great, but it’s a little bulky for my sling pack. So, for hiking, I usually pack the TR-35 loose in the pack, with a rubber band around the bubble wrap. 

The bubble-wrapped TR-35 going in the bag
The bubble-wrapped TR-35 going in the bag

I found that a Crown Royal bag provides a more elegant solution for packing the TR-35 (or other small QRP rig). I just wrap the bubble wrap around the radio and place it in the bag. There’s no longer a need for the rubber band. Plus, there’s enough room in the bag to accommodate the T1 tuner. 

The Crown Royal bag with my TR-35 tucked away inside
The Crown Royal bag with my TR-35 tucked away inside

These bags don’t offer any real protection from the weather, but they look cool. My collection of bags includes a variety of colors, so I can change them to match my mood (just kidding—let’s not get carried away here).

So, there’s a crazy little hack for you to ponder. If you’re a Crown Royal drinker, save the bags. Your radio just might fit in there.

Bottoms up!

73, Craig WB3GCK

The Raddy RF760 Shortwave Radio

A while back, I purchased the Raddy RF750 Multimedia Music Player and did a blog post reviewing that remarkable little radio. The folks at Radioddity reached out to me recently to see if I would be interested in taking a look at their latest offering. A week or so later, I received the Raddy RF760

[Disclaimer:  In the interest of full disclosure, this radio was sent to me free of charge to evaluate and review. This was with the understanding that I would write an honest and unbiased review.]

What It Is

The seller refers to the RF760 as a “full-band radio”. That’s an apt description, since it covers everything from the AM broadcast band up through the UHF range.

Raddy RF760 Portable shortwave Receiver
Raddy RF760 Portable shortwave Receiver

Here are the specs from the iraddy.com website:

  • FM 1: 64.0-108MHZ
  • FM 2: 76.0-108MHZ
  • FM 3: 87.5-108MHZ
  • AM: 520-1710KHZ
  • SW: 2.00-30.00MHZ
  • CB: 25.00-28.00MHZ
  • AIR: 118.00-138.00MHZ
  • VHF UHF: 20.000-520MHZ
  • VHF: 30.00-223.00MHZ
  • VHF: 144.00-148.00MHZ
  • VHF: 156.025-163.275MHZ
  • UHF: 430.00-520.00MHZ
  • WX: 162.400-162.550MHZ
  • Product dimensions: 4.37 x 2.36 x 0.79’’ / 11.1 x 6 x 2CM
  • Lithium battery: BL5C 1000mAH 3.7v 3.8WH
  • Loudspeaker: Ф40MM 8Ω 1W
  • Headphone output: 3.5MM stereo input
  • External antenna hole: 3.5MM
  • Storage Capacity:700 stations in total(FM: 100, MW: 100, SW: 100, AIR: 100, CB: 100, VHF/UHF: 100, UBD: 100)

With the battery installed, the RF760 weighed in at a mere 3.8 ounces (108 grams) on my kitchen scale.

The box includes:

  • RF760 radio
  • 1000MAH 3.7V Lithium battery
  • Earbuds
  • USB-C cable for charging
  • External antenna wire (approx. 10 feet)
  • Wrist strap
  • Storage pouch
  • User manual

RF760 vs RF750

It’s clear from the specifications that the RF760 is not an upgraded RF750. The RF750, with its Bluetooth and ability to play MP3 files, is more of a multimedia player. The RF760 does not have those capabilities, but, rather, provides expanded frequency coverage.

The Raddy RF760 (left) and the Raddy RF750
The Raddy RF760 (left) and the Raddy RF750

In my view, the RF760 is aimed more towards shortwave listeners and scanning enthusiasts. It includes features like selectable bandwidths, selectable demodulation modes on certain bands (AM/USB/LSB/NFM), and adjustable squelch. 

The RF760 also includes a headphone jack (earbuds included) and a connection for an external wire antenna. These features are lacking on the RF750. The RF760 also has a digital display, which the RF750 does not. Both radios are charged via a USB-C connector. 

The RF760’s additional features come with a higher price tag. As of this writing, it was selling for $99.99 USD

My Impressions

The RF760 is one small radio. It’s roughly about the size of an Altoids tin and weighs next to nothing. (It weighs about 0.65 ounces less than the RF750.) You can fit the RF760 in a shirt pocket, and you might even forget that it’s in there. 

There’s a lot going on with the RF760. Even with the power off, a press of any button will light up the display showing time and temperature. Oh yeah, did I mention this thing even has a built-in thermometer? It even includes an alarm clock and a sleep timer. If you can think of a function, the RF760 probably has it. 

The user manual does a decent job of covering the myriad of features in this radio. The small size of the printed manual, however, is a little tough on my old eyes. Fortunately, the Raddy website has a PDF version of the manual for downloading. The softcopy manual allows me to search for specific functions, which is handy. I also stored a copy on my cell phone, so I always have it available. As is typical of manuals for Chinese products, some of the wording is not always clear. For example, a section covering how to delete a station that has been saved to memory is titled “Delete the radio.”

The various configuration options (e.g., bandwidth, demodulation mode, tuning increments) vary according to the band you are on. Once you get the hang of it, navigating through the options and selecting specific values becomes an easy task. 

In the FM mode, the sound quality is reasonably good, considering the RF760’s diminutive size. In all honesty though, I think the RF760’s audio lacks the richness and fullness of the RF750. When using the included earbuds, however, the RF760’s audio is greatly improved. On FM, make sure you have the radio set for the proper de-emphasis (75 microseconds here in the U.S.).

The weather alert function is one of the more important features for me, and I had the opportunity to give it a “real world” test. My area was under a tornado watch, and we had multiple severe thunderstorm warnings. While tuned to the weather band, a long press of the “SET” button places the radio in the “SCAN” mode. When NOAA issues an alert, the radio comes on with a brief tone followed by the weather station’s audio. There’s no loud siren like the RF750 has, but that’s fine with me. After an alert, you need to long-press the “SET” button to go back into the “SCAN” mode. During the storms, the RF760’s weather alert function worked flawlessly, going off three or four times. 

Tuning is interesting in that it uses a combination of two methods: up/down tuning buttons on the front panel and a rotary “shuttle tuning” knob on the right side of the radio. You can select the tuning increments for the buttons, which is helpful. You can also select the digit of the displayed frequency that is adjusted by the rotary knob. Now, I’m an old “knob spinner” from way back, so I’m generally not a big fan of using buttons for tuning. However, once you get the hang of using the shuttle tuning knob, you can tune to a specific frequency quickly. You can also scan the selected band by long-pressing the “up” or “down” tuning buttons.

There’s a lot of information shown on the display panel. On such a small radio, though, I find a few of the smaller items hard to read with my old eyes. Fortunately, these are items that I don’t have to deal with often. You folks with better eyes probably won’t have a problem. 

I haven’t done any formal measurements on battery life, but you should be able to go for days before recharging. The USB-C charging port is handy; I can charge the radio with the same chargers I use for my phone. 

Bottom Line

The RF760 is a small, lightweight, and feature-packed radio. For camping or in my emergency go-kit, I’d go with the versatility of the RF760. It’s like the Swiss Army knife of radios. I especially like how the NOAA weather alert feature is implemented on this radio. However, If I want to listen to music while working around the house, I’d go with the RF750 and it’s superior audio. 

73, Craig WB3GCK

The Raddy RF750 Multimedia Music Player

My (far) better half and I like to keep a radio in our little travel trailer. When we’re camping, we often listen to baseball games in the evening (go Phillies!) while sitting around the campfire. It’s also handy to have a weather radio on hand, when the cell service is unreliable or non-existent. I bought this little radio to see how it compares to the old radio we’ve been using for years.

The Raddy RF750 is sold by the folks at Radioddity. When I went out to their website to buy one, it was showing “sold out.” They had some in stock, however, on Amazon, so I placed my order there. The same radio is also available at a lower price from Chinese sellers branded as the HanRongDa HRD-700. Being the impatient sort, I went with Amazon Prime at a slightly higher price than the $34.99 price tag on the Radioddity website. (When I checked a few days after receiving my radio, Amazon was showing it as “currently unavailable,” and Radioddity was still “sold out” in the U.S. These things must be selling like hotcakes.)

The Raddy RF750 from Radioddity
The Raddy RF750 from Radioddity

What It Is

The Raddy RF750 is a compact multimedia player with a radio that covers the AM, FM, shortwave, and the NOAA weather bands. It has a Bluetooth mode, so it will play audio from your smartphone. The RF750 will also play MP3 files from a micro SD memory card (up to 256GB) you can insert into the unit. It’s powered by a 1000mah Li-ion battery, which you can recharge via a USB-C port on the radio. 

When playing audio via Bluetooth or SD card, the RF750 has an audio equalizer with six preset configurations to choose from. You can also set the radio to scan a band automatically and store the stations it finds (up to 20 stations each on FM and AM, 10 stations on each of 7 shortwave bands). This can be useful when you’re traveling. There is also a sleep timer that will shut off the radio after a user-selected time (10 to 70 minutes).

Here are the specifications from the Radioddity website:

FM: 87.5-108MHz
AM: 520-1720KHz
SW: 5.7-17.9MHz
WB: 162.400-162.550MHz
Memory: Support TF card, Max 256GB
Audio format: AV, WMA
Power supply: replaceable 3.7V 1000mAh BL-5C lithium battery included
Charging: DC 5V, Micro USB-C interface
Size: 3.5″ x 2.4″ x 1.5″
Weight: 0.22lbs

My Impressions

When I first unboxed this thing, the first thing that struck me was the small size. The descriptor, “compact,” is an understatement. It’s smaller than an Altoids tin and just a bit thicker. Weighing in at less than 4 ounces, it won’t add much weight to your go-kit or backpack.

Along with the radio, the box included the Li-ion battery, USB charging cable, wrist strap, a rubberized drawstring storage pouch, and a user manual. The battery was easy to install and charge up.

I powered it up and tuned to a local FM station. Frankly, I was blown away by the sound coming out of this little radio. Apparently, it uses DSP filtering to provide that sound clarity. Given the radio’s small size, tuning can be a little touchy for an old guy with clumsy fingers. Fortunately, there’s a tuning indicator that makes it easy for me to lock in on a station.

I was particularly interested in the weather band capabilities. In addition to covering the 7 NOAA weather channels, the RF750 also includes a weather alert function. In this mode, the audio is silenced, and the radio appears to be scanning the 7 weather channels. I haven’t been able to test this out yet, but I plan to see what happens during NOAA’s next weekly test.

[Update: I set up the RF750 in the “Alert” mode for the NOAA weekly weather radio test, and the RF75o’s alert went off as expected. The only issue is that the siren sound it makes is excruciatingly loud. On a positive note, when a weather emergency happens, you will definitey know about it!]

When I tested the Bluetooth mode, it paired easily with my smartphone. Although my phone’s audio played through the RF750 was nice and clear, I don’t see myself using this function much. 

To test the “Music Player” mode, I copied a few MP3 files to a 2GB micro SD card, which I inserted into the RF750. The sound quality coming out of the tiny speaker really impressed me. I plan to load more of my music collection onto a larger memory card, which I’ll leave installed in the RF750.

I was a little surprised that the RF750 doesn’t include an earphone jack. I would have expected one on a portable radio like this.

The user manual provided is typical of low-cost Chinese products. The English isn’t always clear, but it was enough for me to figure out how to use the various functions.

I have to say, I’m impressed with this little unit and all the features packed into it. It will be a handy item to have around, especially while camping or during emergencies. In fact, during a recent snowstorm, we lost power for a while. The RF750 allowed us to check the local NOAA weather forecast, listen to local news on the AM band, and enjoy some music on FM.

Disclaimer: I have no financial interest in this product. I purchased it with my own funds, and I’m merely a satisfied customer.

73, Craig WB3GCK

Inside My Old Tuner

In a recent post, I wrote about an old antenna tuner I built about 25 years ago. Although a description of it has been online for decades, I never posted pictures of it. So, here it is. 

I originally posted an article about this tuner on my QSL.net website under the title: A Simple and Flexible Tuner for QRP. Once my go-to transmatch for portable use, it had been on the shelf for quite a while. I hadn’t opened the case in 20 years, so it was a nostalgic walk down Memory Lane for me. 

Schematic of the "Simple and Flexible Tuner for QRP."
Schematic of the “Simple and Flexible Tuner for QRP.”

All of the parts used for this project came from my junk box or were re-purposed from other projects. This is the second tuner to inhabit this enclosure, so the variable capacitor and rotary switch were already in place. 

The coil is consists of 40 turns of enameled copper wire on a plastic 35mm canister. The wire appears to be 22 AWG. I wasn’t shooting for any particular inductance value; I just started winding turns. Based on the dimensions of the coil, the total inductance appears to be approximately 31 uH. I tapped it in 8 places and wired it to a rotary switch. I used two-sided foam tape to secure it to the bottom of the enclosure. I left the cap on the film canister so that the lid would press down slightly on it. This helps to securely hold the coil in place.

Inside view of the tuner
Inside view of the tuner

The variable capacitor was salvaged from an old radio by a friend of mine. It’s a two-section capacitor, totaling about 365 pf, according to my notes. I added a switch to select between one or both of the sections. Because the capacitor is sometimes in series with the coil, I used some thin fiberglass material to insulate it from the chassis. 

Front panel of my old antenna tuner. The switch selects one or both sections of the variable capacitor.
Front panel of my old antenna tuner. The switch selects one or both sections of the variable capacitor.

To the best of my recollection, I purchased the aluminum box at Radio Shack back in the day. I finished off the project with some embossed labels made on an old Dymo label maker. They look tacky, but they’re still holding up after all these years.

Rear view of my old tuner. The slide switch on the left selects the confiuration. In the "LO" position, the coil and capacitor are in series. In the "HI" position, the tuner is configured as an L-match tuner.
Rear view of my old tuner. The slide switch on the left selects the configuration. In the “LO” position, the coil and capacitor are in series. In the “HI” position, the tuner is configured as an L-match tuner.

After spending 15 or more years on the shelf, this funky-looking tuner has been seeing a lot more use lately. I mostly use it as an L-Match for end-fed wires. (I’ve only used the low impedance, series connection a few times over the years.) It’s a great portable tuner for QRP when weight isn’t a consideration. 

I have the parts on hand to build a lighter L-match when I need to carry a tuner in my backpack. Until I find the time to put it together, I’ll keep using this funky old tuner.

73, Craig WB3GCK

Old Tuner to the Rescue

According to the weather prognosticators, today is the start of a 4- or 5-day heatwave here in southeastern Pennsylvania. So, I wanted to get out early for some antenna testing before things heated up too much.

I planned to play around with the speaker wire end-fed halfwave antenna I built recently. To do this, I went back to my favorite antenna test range—my daughter and son-in-law’s property. 

I set up the formerly 66-foot wire (now about 63 feet) in an inverted-V configuration. Since the last time I used this antenna, I trimmed off a couple of feet to see if I could get my little Hendricks SOTA tuner to load it on 20M. 

I started with the SOTA tuner on the 40M band and worked a POTA activator in Indiana. I moved up to 20M, but the SOTA tuner wouldn’t tune below a 2.2:1 SWR. 

Before I left the house today, I had the forethought to pack an old antenna tuner I built about 25 years ago. I used it extensively years ago, but I relegated it to the shelf when fancier equipment came along. I switched to the old tuner, which I configured as an L-match. It loaded up nicely on 40, 20, and 15 meters. As a bonus, the old-school tuner gave a good match on 30 and 17 meters. 

My 25-year-old homebrew antenna tuner. It doesn't look like much, but it did a nice job with my end-fed halfwave antenna cut for 40M.
My 25-year-old homebrew antenna tuner. It doesn’t look like much, but it did a nice job with my end-fed halfwave antenna cut for 40M.

After I finished experimenting with the antenna, I set out to make a few contacts. It was a busy day for Parks-on-the-Air (POTA) activators. I worked 10 of them in 8 states plus Puerto Rico. Three of the QSOs were on 17 meters. It was nice to hear POTA activity up there. 

All in all, I was pleased with how my old homebrew antenna tuner performed. I don’t think it will be spending as much time on the shelf in the future.

73, Craig Wb3GCK

My HT Go Bags

I mentioned in a previous post my obsession with bags and cases for equipment. Well, this post is further evidence of that.

Over the past year or so, I purchased a couple of new HTs. It was a long-overdue upgrade. I first acquired a Kenwood TH-D74. About six months later, I came across a deal on an AnyTone AT-D878UV I couldn’t resist. Accessory-wise (batteries, chargers, antennas, etc.), these radios are very different. So, I wanted a way to organize these accessories and pack everything for travel and ARES-RACES events.

After looking at available options, I settled on an electronics travel organizer from a company called Bagsmart. They weren’t very expensive, so I bought one for each HT. I purchased my bags on Amazon for well below the list price shown on the manufacturer’s website. The specific models available on Amazon, however, seem to come and go. 

The bag measures 9.4″L x 7.5″W x 2.8″H and is constructed of water-resistant—not waterproof—nylon. It weighs a mere 0.25kg/ 0.55 pounds. There three padded partitions that attach with Velcro that can be repositioned or removed. The bag also has a zippered mesh compartment under the lid that is great for storing cables, adapters, etc. There’s also a small compartment intended for memory cards or thumb drives. Despite its small size, it has sufficient room for everything I use for each radio. 

My HT "go bags." Several items were left out of the open bag, for the sake of clarity. I often pack a desktop charge, roll-up J-pole, a couple of spare batteries, and a hotspot for digital voice modes.
My HT “go bags.” Several items were left out of the open bag, for the sake of clarity. I often pack a desktop charge, roll-up J-Pole, a couple of spare batteries, and a hotspot for digital voice modes.

These bags have been perfect for my needs, but they do have their limitations. While they offer some protection for your radios, we aren’t talking Pelican cases here. If you need something water-tight that you can bang around on a rock, these bags aren’t for you. These are light-duty bags, to be sure. 

My only complaint with these bags is that the partitions are somewhat flimsy. Something a bit more rigid would be more to my liking. They do, however, keep things separated inside the bag. 

There’s nothing earth-shattering here, but if you need an inexpensive way to organize your gear, this bag (or something similar) might do the trick. The usual disclaimer applies: I have no financial interest in this company or their products. I’m just a satisfied customer. 

73, Craig WB3GCK