I keep saying that I need another rig like I need a hold in the head. I guess I have a hole in my head, because I recently bought another QRP rig.
The rig I purchased was a (tr)uSDX transceiver. I had been thinking about getting one of these little rigs for several months before finally giving in and buying one. I placed an order with roWaves in Romania, and, to my surprise, I had it in my hands five days later.
This rig is only about the size of a pack of cigarettes, but it sure packs a lot of functionality in there. I won’t go through all the specs and functions, but it puts out about 5 watts (give or take) and covers 80/60/40/30/20m. It supports CW/LSB/USB/FM/AM, and you can set it up for digital modes, too.
There are three controls (two push-buttons and a rotary encoder), and they each have multiple functions. So, it’ll take some practice getting this old dog used to the menus and functions.
I set it up on the bench to fire it up for the first time. I connected it to my Elecraft T1 tuner, which was connected to my rainspout antenna. During this initial session, I logged contacts on 40, 30, and 20M. One of those was a very nice chat on 30M with a fellow SKCC member up in Massachusetts. This little rig held up well in my noisy environment.
Hopefully, I’ll be able to take the (tr)uSDX out in the field over the weekend and give it a whirl.
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.
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 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.
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.
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.
I needed another rig like I needed a hole in the head, but I couldn’t resist. I’ve had my eye on the Penntek TR-35 for a while now, so I finally pulled the trigger and ordered one. I considered it a Father’s Day present to myself. Two days later, I had the TR-35 in my hands.
Lacking the patience and the close-up vision for serious kit building these days, I ordered a factory-built radio with the rotary encoder tuning option. Now, I have seen plenty of pictures and videos of the TR-35, but the small size of this rig really struck me when I opened the box. Its footprint is not much larger than a QSL card. It’s a perfect size for portable operating.
Here are some features that drew me to the TR-35:
It covers the bands I use most in the field (40/30/20/17)
Built-in iambic mode B keyer (my mode of choice)
Two CW memories. Perfect for POTA activations, QRP contests, etc.
Separate inputs for paddle and straight key. I sometimes get calls from fellow SKCC members, so it’s convenient to switch instantly to a straight key for those QSOs.
No complicated menu structures to navigate to get things set up. The TR-35 is super-simple to operate, and that’s just how I like it.
The TR-35 doesn’t include a built-in tuner. No worries; I’m going to dust off my little Elecraft T1 ATU and show it some love. An SWR indicator would have been a nice feature to have, but I can get along fine without it.
Taking It For a Spin
I didn’t have a chance to put my new TR-35 on the air until today. I drove over to Valley Forge National Historical Park (K-0761 and KFF-0761) to try the new rig on a POTA activation. Doing an activation with a radio you’ve never used is a little like going camping with a tent you’ve never set up before. But, what the heck, I was a risk-taker today. Actually, I brought a backup rig along, but I never needed it.
I set up the TR-35 in the cab of my truck, along with my T1 tuner. The antenna was my homebrew 19-foot vertical on the back of the truck. As soon as I powered up, I was greeted by lots of loud CW signals. That’s a good sign. I quickly programmed a “CQ POTA” message into one of the two CW memories and got on the air.
One of the first things I noticed is how loud the audio is. I was using earbuds, and I had to turn the volume almost all the way down. The sidetone seemed a bit loud for my liking, but not really much of a problem for me.
Once I got going, I had a lot of fun with this little rig. I easily made contacts on each of the four bands (40/30/20/17). The TR-35 is a joy to operate, and I really appreciate its simplicity. Tuning with the optional rotary encoder is smooth as silk.
After about an hour and a half, I had 24 contacts in the log, with five park-to-park QSOs. My stomach reminded me it was lunchtime, so I packed up and headed home. I left the park feeling very happy about my recent purchase. The TR-35 is going to see a lot of use in the field.
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:
1000MAH 3.7V Lithium battery
USB-C cable for charging
External antenna wire (approx. 10 feet)
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.
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
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.
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.)
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
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
While trying mobile DMR last month, my (relatively) cheap hotspot experienced an untimely death. I set the hotspot aside as a future troubleshooting project.
While the Pi-Zero board appeared to be working, the MMDVM board was dead as a doornail. The OLED display was blank, and the RF side of the hotspot was non-responsive. It also wasn’t interacting with the Internet at all.
The other day, I came across a posting on a Facebook MMDVM page that shed some light on my problem. Some users reported shorts between the internal boards and the aluminum case. This tidbit of information prompted some further investigation.
I removed the top of the case, reinstalled the antenna, and applied power. To my surprise, the hotspot booted up and came back to life. I let it run for a while without the case to verify that all was well. It was.
I noticed a solder connection that extended a little beyond the edge of the MMDVM board. It appeared to be a power connection, so I suspect that might have been what shorted. I also noticed that a single screw and the header pins are all that secure the top board. I’m guessing the board shifted a small amount while mobile causing the short.
To remedy this, I applied electrical tape inside the top cover of the hotspot. Not being 100 percent certain where the problem was, I covered everything except the vent openings. I used a razor blade to trim the tape around the OLED display and antenna jack openings. I also took a file to the little solder blob I had noticed. (I exercised extreme caution in doing this since I’m sometimes prone to creating new problems.)
I reassembled the case and powered it up. Voila! It still worked. Hopefully, this fix will avoid any reoccurrences and make it withstand the vibrations of mobile use.
Although you’re far more likely to find me on CW on the HF bands, I do monitor Brandmeister TG-3142 (Pennsylvania State-wide) on DMR. And, on occasion, I listen to D-Star REF20A.