I came back to CPF and to this thread to share my experience shopping for a very small radio with a clock and an alarm to use mainly when I'm traveling, but also for use when I'm out and about closer to home. I hope others might benefit from the information I've gathered in trying two such radios recently.
I have health issues that require me to now be very careful about how much weight I carry around with me when I travel, or anytime I leave my apartment. For that reason, in recent years I have had to replace many items I used and liked very much with lighter weight versions, whenever possible - from clothing to electronics to bags, etc. When shopping for a travel alarm I therefore had to find a radio as light and small as I could, but of course I was looking for quality and the features I like and can use. Not an easy task, it turned out.
I found two products I was interested in, based on my usual intensive search of the web, reading reviews, and watching videos. The first one I tried was the Prunus J-125 (newest version). I found it on sale for about $12 on Amazon. The price was right, and it seemed on paper to have a wide array of features found on larger and more costly radios: it is very small (about 4.0 by 2.4 inches), and has a clock (12 or 24-hour clock), an alarm (awake to beeping or the radio), memory presets (30 each for AM and FM), a sleep function, and a 3.5mm earphone jack. The radio operates on two AAA cells. There is also a key lock function, and the FM mode can be turned on in stereo. There is a nice amber backlight for the display, which is easily readable. Tuning can be advanced one step at a time, or you can hold down the tuning buttons and start a more rapid scan for an active frequency. The reception sensitivity on FM was good for a tiny radio with an equally tiny antenna. Even some weaker stations were listenable, although weaker stations were not coming in as strong as on a larger radio.
When I took delivery of the radio, however, I found that the minimum volume selectable using the volume buttons is way too loud for me when I used the earphone jack to listen through earbuds. The other problem I had with the Prunus was that the alarm always automatically comes on at a very loud volume level, whether it is set to use the beeping sound or the radio. That is probably a great feature for most people - but not for me. I don't need an alarm that loud, and I'm afraid it will disturb people in adjoining hotel rooms. While Prunus customer service was very accommodating and sent me a second radio, due to display cover damage on the first unit, I ended up returning the J-125.
Fortunately, there was another product to try with similar dimensions: the Kaito KA220W, also available at Amazon for about $15. When I received the Kaito product, I could tell it is built solidly - it has more heft than the Prunus product, in my opinion. This radio is 4.25 by 2.25 inches. It operates on two AAA cells. The display characters are larger than in the Prunus product, and the amber backlighting is especially strong and even in this radio. I also like the simplicity of its controls. This radio also has a key lock function, and the clock (24-hour clock only) and alarm (awake to beeping or the radio) are easy to set. Unlike the Prunus product, the KA220W has a dial for volume adjustment. That enables the user to turn down the volume very low for listening through the earphone jack more comfortably. This radio, like the J-125, can be tuned one step at a time, or more rapidly "scanned" to find an active station by holding down the tuning buttons. I am under the impression that the antenna on the KA220W might be a bit longer than the antenna on the J-125, and it feels a bit more solid, too. The sensitivity of the KA220W on FM also seems good for its diminutive size and the small antenna, although weaker stations are not a strong point of this radio. The speaker obviously has limitations due to its size, but it sounds deeper and richer than I expected in a tiny radio.
Unfortunately, the KA220W has no memory presets, and does not feature an FM stereo mode. The lack of these features is not a deal-breaker for me, as I don't need either of those two features to use the radio for a travel alarm or a handy radio to carry around town. However, like the Prunus product, the Kaito radio's alarm function is not ideal for me. While the alarm starts at a low volume using either the beep or the radio, within a few seconds it rapidly increases to a very loud volume. As explained above, this is not ideal for me, but given all of the other features of the KA220W, and its quality and performance, I am keeping it and will use it as my travel clock radio.
I also recently picked up a Retekess PR15. It certainly seems to justify its excellent reputation among portable radio enthusiasts. The sensitivity, sound, and quality all seem outstanding for its ultra-mini size. Another great value, especially with the NOAA weather frequencies included - and an excellent choice for those of us who must always keep the weight of the items we carry to a minimum.