TechMinds: A Review of the RigExpert FobosSDR
Earlier this year the Ukrainian company RigExpert released the FobosSDR, and only recently has it become available to most people in the world via global resellers. FobosSDR is an RX-only USB 3.0 device, with a 100 kHz to 6 GHz tuning range, 50 MHz of bandwidth, and 14-bit ADC resolution. Current pricing from US resellers is US$395 and from EU resellers around 495,00 €.
Recently Matt from the TechMinds YouTube channel reviewed the FobosSDR, showing an unboxing, description and review of the hardware. Unfortunately, while the specs on paper look good, Matt notes that the FobosSDR does not perform well.
In the video, Matt starts by testing around the broadcast FM band and shows how the FobosSDR suffers from multiple mirrored signals, even with the gain settings turned right down. He notes that other similarly priced SDRs perform a lot better and that even an RTL-SDR performs better.
Matt then goes on to test the HF bands, noting that there is no gain control available on these bands and that there are also extreme levels of signal mirroring all across the HF band.
Unfortunately, we are starting to see other similar reports about poor performance from the FobosSDR. For example, on arcticdx's blog he also does not recommend the SDR [1][2],
I looked at the Block Diagram in the Fobos SDR receiver datasheet, and this only has 2 frontend filters a Low pass filter with a cutoff at 2.35GHz and a High pass filter with a cutoff at 2.45GHz. What this means in terms of RF performance is that without external bandpass filters, this thing will be bad really really bad, but if you add a bank of external filters it might be interesting.
Some parts of the design look like they were cloned from a HackRF One.
From my experience prices seem to be in Europe for an identical product in average higher compared to the US. You also have to know that VAT is included in the price in Europe. VAT is currently around ~19%, only for B2B use may the price be quoted without VAT.
Since it is coming from Ukraine, i wonder why it is much more expensive in Europe than in the US!