Back in 2020, I started fooling around with digital voice modes. I don’t really use them a lot, but there are a couple of DMR nets I like to check into each week. I recently started using the WPSD software instead of the Pi-Star software I had been using on my two hotspots. Just for the heck of it, I wanted to try upgrading the old Raspberry Pi Zero board on one of them to something more capable.
According to the documentation, WPSD was never written for single core processors, like the old Pi Zero W board in my hotspot. The developer recommends a Pi Zero 2 W or better. While it will work on a single core Pi, it runs slower—I can attest to that. I also noticed that CPU utilization was well over 100% at times. With its quad core processor, the Raspberry Pi Zero 2 W is supposed to be five times faster than its single core predecessor. So, I was hoping to see some general performance improvements and faster boot-ups after this upgrade.
In the interest of full disclosure, I’m no Raspberry Pi expert—far from it. I had to do some online research before launching into this. It looked simple enough; the Pi Zero 2 W board is a drop-in replacement for the original Pi Zero board, so it seemed simple enough.
I bought a Pi Zero 2 W board on Amazon for about $28 (US). The board didn’t have the header pins installed, so I bought some. I bought a box of 40-pin headers for less than $10 (US). I now have more of them than I’ll use in my lifetime.
I took advantage of a rainy Sunday to do the upgrade. First, I needed to install headers on each end of the Raspberry Pi’s GPIO area. The two headers had two rows of five pins each. With the help of an Xacto knife, I snapped the pieces I needed from one of the (many) 40-pin headers I now own. With my aging eyes, I needed to use a lighted magnifying glass to do the soldering. To avoid melting the plastic, I allowed some cooling time after I soldered each pin.
The new Pi Zero 2 W board installed in the hotspot case. The two headers I soldered in are towards the front.
The MMDVM board installed on top of the Raspberry Pi board.
The is the fully-assembled hotspot. This pink section to the right is a piece of paper I used to cover some overly-bright LEDs.
From there, it was a simple task to disassemble the hotspot, swap boards, and put it back together. I estimate that the hardware part of the upgrade took all of about 20 minutes.
I had previously burned the WPSD image on a new Micro SD card, so it was ready to go. When I inserted the card and powered up, the hotspot booted up in a minute or two. After importing a backup WPSD configuration file and doing a couple of tweaks, the hotspot came to life. Success!
The performance improvements were immediately obvious. The dashboard and configuration web pages were much more responsive, and the CPU load typically stays under 20%. It’s been running for a week now, and it’s been rock-solid. Since this upgrade went so smoothly, I went ahead and upgraded my other hotspot. That one was just as easy and is also working great.
For you Raspberry Pi power users out there, this is pretty trivial stuff. Yeah, I guess it is. But it was an easy and fun little project, and I learned a bit about Raspberry Pi boards in the process.
Sometimes I get excited over some of the most trivial things. This is one of those times.
I wrote about my Junk Box Loading Coil in a recent post. I normally keep the loading coil and my 12-foot telescopic whip antenna stashed away under the backseat of my pickup truck, so it’s handy for spur-of-the-moment activations. I also keep a couple of Jackite poles and some other gear under there. While the coil is pretty rugged, I just didn’t feel right about cramming it in there unprotected. By pure dumb luck, however, I stumbled on the perfect storage solution.
While mindlessly browsing the Internet a while back, I stumbled across something on a Chinese seller’s website (Temu.com) that caught my eye. It was a storage case that was probably made for something no longer sold. I’d provide a link, but products quickly come and go on this website. The website listed it as “Simple Portable Storage Zipper Bag, Travel Electronic Tools Organizer, Zipper Container.” Wow. That’s a mouthful.
I had seen similar cases on eBay, but not in this particular size. Given the listed dimensions, I thought it might be a good fit for my homebrew loading coil. At the time I placed my order, it was selling for $7.98 USD.
This is the case I bought to use with my Junk Box Loading Coil.
The container, along with a few other things I ordered, arrived on my front porch eight days after I placed my order. Voila! The case was a perfect fit for my loading coil. In fact, it looks like it was custom made for it. It’s semi-rigid, so it affords some degree of protection. It’s definitely not elephant-proof, though. There’s an elastic strap inside that helps hold everything in place.
My Junk Box Loading Coil tucked away in its new storage container
I’m not exactly sure what this case was intended to house, but it’s perfect for my application. So now, my coil will stay clean and protected, while waiting under the backseat of my truck for my next POTA activation.
I bought the Evolve III Maestro E-Book about nine months ago. Having used it for various ham radio applications during that time, I thought I’d offer some updated thoughts on this inexpensive laptop.
Spoiler alert! There really isn’t anything I dislike about the Evolve III laptop. Sure, it’s not the speediest machine ever built, but it has stood up to every task I’ve thrown at. I regularly use it at home for Winlink, NBEMS, and VarAC. I’ve also used it for these modes in the field for ARES-RACES exercises.
The Evolve e-book in use during this year’s Field Day
Power Considerations
Besides its small size and low cost, the thing I like best about the Evolve III is its battery life. Depending on what I’m doing, I can get eight to ten hours of run time. That’s way more than I need for my typical portable outings.
Since the “wall wart” charger it came with outputs 12VDC, I can charge the laptop from a 12V battery. For charging in the field, I bought a 6-foot cable on Amazon that has a 3.5mm x 1.35mm coaxial power connector on one end. On the other end, I added a 12V accessory plug (cigarette lighter type). I also built a second cable with an Anderson Powerpole connector.
A charging cable I built with a 12V cigarette lighter type plug
A 12V charging cable I built with a Powerpole connector
For Field Day, I operated all day without having to charge the laptop. I couldn’t have done that with other laptops I have used in the past. Before turning in for the night, I connected the Evolve to a 17 A-H gel cell battery to charge it overnight. (I had a fused 12V socket installed on the battery.) When I woke up during the night, it was fully charged, so I disconnected it. The Evolve lasted the rest of Field Day without further charging.
Field Day Configuration
My Field Day configuration made full use of the Evolve’s capabilities. I used it for logging, connecting to our shared log file via Wi-Fi. I also used one of the two USB connectors to drive my WKmini Morse interface to send CW with my KX3.
Since I only had one more USB connector available, I used a 3-way USB splitter to accommodate the other devices I needed to attach. I had the receiver for my wireless mouse attached to one port on the splitter and the KX3’s rig control cable connector to another port. I used the third port to connect a thumb drive, which I used for exchanging files with another Field Day participant.
This is a USB splitter I bought at Staples years ago. The extra USB ports came in handy during Field Day.
For backups, I had my N3FJP Field Day logger configured to save backup files to an SD card. Since my backup files included the entire networked log, I had everything I needed to submit our group’s entry on my laptop when I got home.
With all that going on, the Evolve performed flawlessly.
Some Additional Thoughts
I recently heard from a couple of hams who received Evolve laptops with a USB-C charging port. This is a recent design change, I suppose. I don’t have any hands-on experience here, but I think this might actually simplify things in the field. A 12V socket connected to the battery and a commercial 12V cell phone car charger should be all you need to charge the Evolve. Most cell phones and devices seem to favor the USB-C connectors these days, so suitable 12V car chargers are easy to come by.
So, if you couldn’t tell, I’m a big fan of the Evolve III Maestro E-Book. So far, I feel the $89 I paid for it was money well spent. I’m hoping I can get several more years of good service from it.
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.
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
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.
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.”
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.
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 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.
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.
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!
I don’t have a link to the source, but my XYL says she found it on Amazon.
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
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.
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 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
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
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.
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.
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
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.
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
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.
WB3GCK QRP Amateur Radio 