I picked up the second-generation ADTH ATSC 3.0 NextGen TV tuner on Amazon the other day (compensated affiliate link) to see how it performs. If you’re not familiar with it, the device lets you receive both traditional ATSC 1.0 and new NextGen TV broadcasts, including those that use DRM encryption. It can record encrypted broadcasts to an SD card, though playback only works on the box itself. ADTH also claims that a “gateway” firmware update will allow more flexibility later.
See it in action in my latest review.
What caught my attention was the box’s promise of “unconnected DRM,” suggesting it wouldn’t need an internet connection to tune in live television. The first-generation model required one, which made no sense for free over-the-air TV. So I decided to test that claim directly—no Wi-Fi, no Ethernet, just power and an antenna.
Out of the box, the tuner booted up and I was able to bypass the WiFi setup. I manually set the time and region since there was no internet connection to do it automatically. That step alone might frustrate less technical users. The channel scan found about 56 stations, and I was able to tune both encrypted and unencrypted channels without connecting online. My local encrypted CBS and NBC affiliates came through fine, confirming that offline decryption now works.
Unfortunately, HDR output was dim on my non-HDR display. There’s no option to disable HDR in the settings—just “always” or “adaptive”—and color-space adjustments made no difference. That means the firmware still forces HDR on displays that can’t handle it.
Recording worked in a limited way. I could start a recording to the SD card and even switch channels on the same broadcast frequency, but the box only supports a single tuner. Once a recording finished, I couldn’t find where it went. The “library” section that should have contained my recordings was missing until I connected to the internet and performed several beta firmware updates. ADTH is advertising DVR functionality and offline use simultaneously, but in practice, the DVR only becomes usable after downloading updates and enabling a beta mode.
After a few updates, the library finally appeared and playback worked, including for encrypted channels. It did play back those encrypted recordings when I disconnected it from the Internet. However, the software remains buggy—the interface froze at one point, requiring a power-cycle. The tuner also runs an old version of Android 11 with a 2021 security patch, making it dangerously out of date.
So, while the device technically works without the internet for basic live TV—including DRM channels—most of its useful features require network access. The HDR bug, outdated software, and rough interface make it feel unfinished. It still costs $100, far more than the $20 tuners available for ATSC 1.0, largely because of the licensing fees and development costs tied to encrypted broadcasts.
This is one of the few options that can handle NextGen TV’s DRM, but it’s hard to imagine a casual viewer getting this up and running smoothly. I’ll keep testing it as updates roll out, but this second-generation box feels like another rough draft in the long transition to ATSC 3.0.