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The Zhiwhis ZWS-777 (aka HanRongDa HRD-777 / Raddy RF750 Plus) is a little product, a mere 2.8″L x 1.7″W x 2.3″H plus a 10.6″ telescopic antenna. It’s also hefty at 7.7 oz. with BL-5C battery and accessory ferrite loop antenna, compared with 4.7 oz. for the larger HRD-701. I suspect some of the weight is due to the metal case and perhaps the 3W speaker (both use the same battery).

This a member of the military-styled radio class from Shenzhen Hanrongda Electronic Corp: the HRD-700, ZWS-702, ZWS-702X, HRD-A320, and HRD-C919. It has sort of a geeky retro military feel to it, from the olive drab color, the five-pointed stars stamped in various places and the schematic circuit symbols around the speaker.

I spent a very long time last year attempting to receive shortwave signals encoded with a scheme called DRM, or Digital Radio Mondiale. The process required an SDR and installing software called DREAM and some other stuff. Long story short: I never got it working.

I found on the public LiteMALADSP MLite-880 Facebook group that new beta firmware V1.60 for the LITEMLADSP MLite-880 includes a DRM decoder. The firmware is a available in the group’s files.

Update: As of today, V1.60 is officially released and available on the One-Click installer.

After the firmware update, a new entry, DRM, appears among the modulation types. Google AI says:

Digital signals like DRM require careful gain management. If your signal is overloading, press the “5” button, [next page,] then “2” to access the spectrum/gain menu, and manually back down the gain. Setting it too high can distort the signal and break the digital lock.

Because DRM is a “perfect or nothing” digital standard, the built-in telescopic antenna is often insufficient for clean decoding. For optimal results, connect a high-positioned external random wire antenna or a magnetic loop antenna.🤖

One way to find DRM broadcasts is to search EiBiSpace for “DIGITAL”. Most entries are from China, but a bit from the BBC, France (RTF and RFI), Voice of Romania, Trans World Radio, Radio New Zealand, Funklust (Germany), KCBS North Korea, and the enigmatic Music 4 Joy also from Germany.

Google AI suggested that the easiest catch in Virginia is probably Radio Romania. I checked and found Radio Romania on in digital at 1700 UTC on 13750 kHz, and it was glorious! I was out on the patio with the 20′ WUT (wire up tree) antenna connected.

AAC is the standard DRM audio codec and 11.6 is the audio bitrate. d = -127 Hz is the deviation between the transmitter’s frequency and the receiver’s tuning. DRM-B is the transmission mode that indicates a bandwidth of about 10 kHz. Symbol synchronization of 88% is quite good. Anything above 70% is usually enough for stable decoding.

“Tiganesti E1” on the display refers to a specific shortwave transmitter and antenna configuration at the Țigănești transmitter site in Romania — one of the main facilities used by Radio Romania International (RRI) for its shortwave broadcasts.

Instead of a spectrum display, the MLite-880 shows a Constellation Diagram on the left in DRM mode.

“Imagine the transmitter is throwing darts at a dartboard. Each dart is a piece of digital information. A perfect signal means all the darts hit the bullseyes. Noise, fading, and interference make the darts scatter. The constellation diagram shows where the darts actually landed.”🤖

That was my first impression, how small it was. The case is metal and the device feels heavy.

I already talked about the Zhiwhis ZWS-777, aka HanRongDa HRD-777, aka Raddy RF750 Plus in Looks Cool: Zhiwhis ZWS-777. I said I wasn’t inclined to buy one. A few bits of new information piqued my interest. First, it appears intended to be a successor to the HRD-700 — a radio I passed up years ago because there was no digital display, opting for the HRD-701 instead (a treasured yellow radio with a great speaker).