We're happy to announce that the RTL-SDR Blog V4L (Lite) model is now available for purchase in our store! Our initial production batches are small, so we will have limited stock at first, and the first batches will be available for shipment only from our warehouse in China. But we expect to ramp up production and get stock on Amazon over the next 2-3 months.

Currently, only our blog store (via the red add to cart button), official eBay listing and Aliexpress listing sell this product. Amazon will be stocked in about 2-3 months. 

As you may already know, the Blog V4 line of products was recently made end-of-life due to the exhaustion of the stockpile of Rafael R828D tuner chips that the V4 models require. The R828D chip has not been in production for many years, but we were able to access a large stockpile of the chip via our contract manufacturer relatively cheaply, which made the Blog V4 models cost-viable. We predicted that the V4 models would be in production until the end of 2026, as we expected to be able to purchase a few more R828D chips from third-party stockpiles at slightly higher prices. But it turns out that the last few chips available in those third-party stockpiles were all counterfeits (they had put legitimate chips in the first 100 spaces in the reel, then for the rest they had lasered the R828D logo on a totally different chip with the same package size and expected us not to notice!).

We have recently secured a confirmed good stockpile of Rafael R828S chips via our contract manufacturer, which allows us to produce the new Blog V4L (Lite) design. Compared to the R828D, the R828S is a variant with one fewer RF input. This means that instead of a triplexed filtered input, we can only do a diplexed filtered input. Hence the 'lite' designator, as the design is identical to the original V4 models, except for the triplexed input filtering feature. This lack of filtering comes with a minor upside: improved sensitivity due to less filtering losses on the front end.

Of course, the downside is that the front end is not as well filtered against strong signals, so the two-tone test produces identical results to the V3 model.

The V4L still maintains the same built-in HF upconverter architecture of the V4 models and, like the V4, has the improved PCB layout, 1PPM TCXO, 4.5V Bias Tee, bias tee LED, improved power supply, and more.

Another upside is that the R828S chip is cheaper, and so we can sell the Blog V4L at a slightly lower price!

We note that, like the V4 models, the V4L is also a limited edition product. The V4L also relies on a large stockpile of a chip that is no longer in production. We expect the V4L chip stockpile to last about one year. Beyond that, we have a solid idea for V5 model design that is still in the early stages of development, but please don't expect any further news on that until 2027.

As the R828S chip has not been used in an RTL-SDR model before, the official Osmocom drivers do not yet support it. We have submitted a patch request through their channels, but have not heard back yet. - Update: Osmocom has updated their repo and added V4L support.

For now, V4L users can use our rtlsdrblog/rtl-sdr-blog driver fork available on GitHub, with Windows DLL Releases. ExtIO users can access a compatible Windows ExtIO here. We have submitted patches for the Android RTL-TCP app as well. More information about driver compatibility can be found in the V4L user's guide.