Amazon surprised me by delivering my new Raddy RF75A 5 days early. I already knew it was small, but the size is still remarkable.
The RF75A is slightly taller than the HanRongDa HRD-701, but much thinner. Here the already compact Tecsun PL-330 is shown in the rear. The actual dimensions are 92 x 53.2 x 26 mm. It’s also appropriate to show the two front radios together, since they both come from the same company and share many concepts and features. Both share memory systems and both support Weather alerts. They both play MP3 files and support Bluetooth. The RF75A is also sold under the HanRongDa brand as model HRD-787.
While on the topic of the HRD-701, I hasten to praise the RF75A for an improved manual over the HRD-701 manual that calls the tuning knob a “pulley.” But still the manual needs work where some of the sentences don’t quite make sense. The manual linked is newer than the one that just came with my radio in layout, but the text seems pretty similar. Readers here know that I have been very critical of radio manuals that are confusing, incomplete, written in bad English and that omit critical information. The HRD-701 earned that criticism. The RF75A shows some improvement. I give it a B- grade (see Errata section at end).
Unboxing
Not really, but the box contains:
- Raddy RF75A radio
- Hand strap
- 21-page Operational Guide
- 12-page APP Instruction Manual
- Earbuds
- External wire antenna with clip
- USB-C data/charging cable
- Amply-sized carry bag
Radio-C
What sets the RF75A radio apart from every other one I have owned is the app that not only allows you to control the radio as if you were pressing its buttons, but also adds features and buttons beyond what the base radio provides. The first example of that is the Record function: the radio can store what it is receiving on a micro SD card, but the recording can only be activated with the app. The second really blew me away: you can press a single button on the app to set the radio’s clock from the phone’s clock. Probably the most useful app feature is direct entry of frequencies. In music play mode the listener can select the song by number.
Not only does the app provide remote control of the radio, but also remote viewing. The user can view the frequency set. It shows the file name of the MP3 file playing and even displays signal strength and S/N radio, data not shown on the radio’s display.
The app is called “Radio-C” for Android and “Radio-CT” for iPhone. There is also an app for HarmonyOS.
Audio
The tiny 40mm speaker is rated at 3W, and the radio’s volume can be turned up to an uncomfortable level. It’s a good sound for such a small radio, but more suited for popular music than symphonic to my ear. The SOS siren is extremely loud (independent of the volume control). The Bluetooth connected tone is louder than it needs to be.
I tried an older 16GB micro SD card that crashed the XDATA D-109 (known fault with some older 16GB cards) and the Raddy handled it with ease. It supports up to 256GB cards (over 64GB requires exFAT formatting). Up to 65,535 songs are supported. Songs can be selected by number using the app. The radio alone can just skip forward and back. The radio plays MP3, WMA and WAV files.
There are 6 “equalizer” settings available for digital audio files, but not for the radio.
Plugging the radio into a PC with a USB-C cable allows direct access to the micro SD card from Windows Explorer, making it easy to copy music to the card. Also when connected, the radio becomes a USB speaker for the computer, and using the volume control buttons on the radio changes the volume setting on the computer. I recommend not trying to access the MP3 files on the radio from Windows applications, like Groove Music; it’s better to copy the files to the PC first.
The app can signal the radio to start recording on the micro SD card and recordings are stored in a separate folder in MP3 format at 160 kbps. The one disappointment here is that the radio does not support FM stereo and when recording is active, one cannot tune the radio to another station; it’s locked. The clock time is not stored as the Date Modified in the drive directory (this is also the case with all the other radios with a record function that I have tested).
I compared the FM headphone experience to my Tecsun PL-330 using decent set of Sony headphones and an A/B switch. Mid to low tones were noticeably missing on the Rady, but overall it was good to listen to. Also the headphone cord acts as an antenna on the FM band, and I was actually able to receive more stations with headphone cord than I could with the shorter whip antenna.
Controls
There are a total of 9 buttons, and no switches or knobs. The controls seem logical and well-placed. Power button is first on the front of the radio. The next thing to do is set the band — second from the top. Tuning is accomplished with up and down arrow buttons on the side (where one would also find a tuning knob on most radios). Volume up and down is the bottom two buttons. The dial light, flashlight and SOS alarm are controlled by a left-side button with press, double press and long press respectively. Short presses of the Lock button provide multiple functions, such as SW band switching and micro SD card player mode (repeat all, repeat one, repeat file or random).
A brief tap of the power button when the radio is off turns on the display light and displays the clock (what the manual calls “clock mode”). A second press turns on the radio. With the radio on, a quick press mutes the radio or pauses the music play, and a long press turns the radio off. A long press on startup allows setting the sleep timer.
With that said, some buttons on the radio serve up to 4 functions, depending on operating mode and whether the press is long, short or double. For example the LIGHT/SOS button turns on the display light with a press, the flashlight with a double press, and the SOS alarm with a long press; when the flashlight is on a single press turns if off.
Some of the settings can get complicated, such as setting the VHF bandwidth. The manual provides a flowchart to walk the user through the process. When the flowchart begins with the CLOCK symbol, that means that the radio should be powered off to perform the function.
The display illumination changes according to Band/Mode. Bluetooth is dark blue. Weather band is red, as shown in the photo. VHF and FM are green; MW is purple; SW is yellow; TF card playing is light blue.
Because the display illumination aggressively turns off after 5 seconds, it’s easy to forget that the radio is on when muted and not on a station (a tuning LED lets you know it’s on when a station is tuned). Long press the button to turn the radio off. I’ve left mine on several times in the first day.
Cautions
Every reviewer I’ve read has commented on the very thin antenna and cautioned about accidentally bending it. I agree. It’s significantly thinner than the one on the similarly-sized HRD-701.
The SOS alarm is quite loud and one wouldn’t want to activate where it could startle others or annoy the neighbors. There is a way to disable the SOS alarm described in the manual.
Radio
The radio receives MW/FM/SW/WB/VHF. The frequencies are:
- MW: 570 – 1710 kHz (9 or 10 kHz step)
- FM: 64 – 108 MHz
- SW: 4.75 – 21.85 MHz
- WB: 7 NOAA channels
- VHF: 30 – 199.975 MHz
Note that the VHF band overlaps both the FM and WB frequencies. I can use the weather band to access my local NOAA station on 162.450 MHz, but get the same signal by tuning VHF to that frequency. For FM, one would need to change the VHF bandwidth to listen to FM broadcast stations. There is a setting that disables the VHF band altogether.
Direct frequency entry is possible with app, but on the radio itself there are up and down tuning buttons on the side. A single click advances to the next channel. A long press scans quickly, and continuing the long press results in a super speed forward scan. An ATS shortwave scan on this radio takes about 6 1/2 minutes. In the super fast mode, it takes about 10 seconds from bottom to top. It can race from 30 mHz to 200 mHz in only 26 seconds. Repeated presses of the orange Lock button advance the frequency across the 10 covered shortwave bands.
The radio has a tiny antenna, only 13 inches long. Don’t expect much from the whip antenna alone. It’s notable that the seller has chosen to include an external antenna in the package. I’ll do my shortwave testing with some sort of external antenna.
After I have more experience, I’ll likely fill in more in the performance section that follows.
MW/FM
The easy test is the daytime MW/FM band scan that I have done on several other radios with their internal antennas:
This radio with 8 stations did quite well among low-end MW receivers in my weak signal area, but nowhere near the standards for a more expensive mid-range unit. It was middle of the pack in FM performance; however, there was significant strong station bleed onto adjacent channels, and sometimes 2 channels. I wouldn’t pick this radio for FM DXing.
Note that MW reception is best with the radio held vertically directly facing the station. Some vertical format radios work better on their sides — not this one.
Shortwave
My first test on shortwave was to do an afternoon (around 2:30 PM local time, UTC – 4) bandscan outdoors using my 20-ft wire up a tree antenna (WUT). After it finished, I scanned with my Tecsun PL-330 as a “good” reference radio. Of course, this doesn’t account for variability between the signal levels required for a station to be selected, but I think it’s a useful test. I did a manual forward scan on the RF75A and an ETM+ scan on the PL-330 to save time and video editing. The RF75A searches all frequencies within its 4.75 – 21.85 MHz range, while the PL-330 only scans the broadcast bands, omitting, for example, the locally reliable Canadian time station CHU on 7850. I added these to the end of the video following. I edited out large sections of empty space from the RF75A.
The reader can judge the comparison for themselves. It seemed to me that the Tecsun PL-330 was a more sensitive radio with less noise. But the PL-330 is also a more expensive radio, it lacks record/playback capability and it also doesn’t have an app.
I said that I didn’t expect to receive much on shortwave with the whip antenna, but I did try it around 06:00 UTC indoors in my very electrically noisy house. I was able to receive Radio Habana Cuba on 6000 kHz, as well as a listenable CFRX in Canada on 6070. I also received WWV and WWVH weakly on 10000.
I ran a second from the feed from an MLA-30+ that was outdoors in a soaking rain. This was sort of an experiment, both making a video while the radio was controlled from the app, and using the audio from the radio coupled to the camera with a cable.
Here’s one final video of the RF75A connected to the MLA-30+ just after midnight UTC. The rain had stopped and the antenna should have been dry.
I did some additional testing after 2AM local time and received these signals below in my basement with just the whip antenna. The signals were recorded by the radio.
VHF
I don’t have a general coverage VHF receiver and I have no experience scanning those bands. Because of the huge band, 30 – 199.975 MHz, scanning would take a long time and the traditional VHF scanner function would be, I suspect, impractical. There are 100 memory locations, and the VHF user might want to create presets for stations of local interest.
I have so far not received any VHF transmissions except the NOAA weather station and FM broadcasts.
Battery life
I haven’t tested the radio’s battery life except to note that with some use the battery indicator went down from 3 bars to 2. The battery is advertised as 1000 mAh. The specifications say that the maximum current is < 820 mA. At that maximum rate the battery should be depleted in a little over an hour; however, that would require running the speaker at full volume, which one would never do. The radio’s volume control goes from 0 – 30. Comfortable listening for me is at 8.
Technical specifications
Errata
The manual had one significant error on the topic of accessing station presets. It says: “7.8 Press [MODE] to pick up the station. When [PRESET **] is displayed press [the up and down arrows] to select the station number.” The button to press to access presets is the [MEMO/SET] button. I found out the right combination by looking at the functionally similar HRD-701 manual. I sent an email to their support address.
There are two errors on the radio itself. The first is on the display where a signal level is shown as a bar graph; it’s labeled “LEVER.” The second is the button labeled [BAND / MOD] should be [BAND/MODE] as it is referred to in the manual.
I experienced lock-ups on my computer accessing the audio files on the radio. It worked, and then it didn’t. I had to unplug the USB cable, turn the radio off and back on, and then replug the cable.
Room to improve
Certainly the ability to initiate recordings on the radio itself would be a plus, as well as the ability to tune the radio while it is recording. After using the Record feature a few times, a rather serious design flaw came to light, identifying the recordings. A common use case would to be a listening session where I record something interesting. The source of the signal might not be self-evident, but some research with station schedules could figure out the station and I could log it. There’s nothing to link the log entry to the recording. It’s not linked by time because every recording has the same timestamp. The files are just numbered sequentially. When the recording is made, nothing on the radio or in the app tells you the file number being recorded that could be entered in the log. A good solution would be for the timestamp on the file directory to be the time from the radio (or the date and time from the phone!), and an even better solution would be to do what SDR# does, put the frequency and time in the file name. The way it works now is a real pain. The workaround is to use the app immediately after recording to scroll through the files until the last one is reached, and then record the filename displayed there in the log.
Another plus would be a user-replaceable battery. Of course all around improvement in reception performance and better selectivity on FM would be a plus, but this is a tiny radio.
One particularly annoying design issue was also found on the HRD-701. This radio has what would be called VF/VM mode on other radios like the Tecsun PL-330 or the XHDATA D-109. The mode determines whether the tuning control advances through frequencies (VF) or memory presets (VM). The problem here is that the radio automatically switches from VM mode back to VF if no key is pressed within 5 seconds. That makes it difficult to go through the presets, listening to each one for a bit (longer than 5 seconds). The 5-second timer also applies to display illumination which cannot be set to stay on.
Conclusion
Like Todd Erbert, I give this radio a “maybe” rating. It’s certainly fun, and the ability to tune with the app is very cool. It supports recording, and it covers VHF territory that none of my other radios cover. The small size makes it ideal to carry along. After writing the review and making my first video of the radio, I realized that I could make videos of the radio without any hands in the way, controlling it all from the app.
My current thinking is that this would never be the one radio for an SWL. Performance is just not that good compared to alternatives in the same price category like the Sihuadon R-108.
I moved the radio into my “upstairs” category, a rather elite group of radios that I might want to pick up on the spur of the moment, in contrast to the larger collection that includes some serious radios downstairs where the MLA-30+ terminates. The RF75A joins the Tecsun PL-330 and the XHDATA D-109 and D-219.
I’m going to see if this radio grows on me. I’m considering it replacing my Degen DE15 as the “car radio.” Weather band is the advantage the Raddy has the over the Degen for mobile — that plus direct frequency entry via the app, USB and a record function.
PS: This question reminds me of an article I wrote years ago about two Windows tablet computers. One was bigger and more powerful and the other more compact but less powerful. I couldn’t decide which I liked better. Now that question is resolved in favor of the larger Microsoft Surface, with the other one totally neglected. We’ll see how much use the smaller RF75A gets a year from now; however, as far as the HanRongDa HRD-701 is concerned, I can’t think of any further use for it.
Update
I’ve started carrying this radio around in my shirt pocket. It’s small and light enough to do that without it getting in the way. It has afforded opportunities to hear things I wouldn’t have normally heard if I had to go and get out a radio to listen. Here’s an example of one of those happenstance sessions, a wonderful signal from Spanish National Radio: