AFEDRI SDR-Net

The AFEDRI SDR-Net is produced by Alex Trushkin, 4Z5LV. It is a direct sampling SDR with a 12-bit 80MHz ADC that covers 0.1 to 30.0 MHz. It supports both USB and Ethernet interfaces, and can be used with Winrad, Linrad, HDSDR, CuteSdr, Sdrdx and SDR-Radio/SDR-Console software. It can record up to 1.25 MHz bandwidth to disk for later playback and analysis.

The SDR-Net X2 version has two receiver boards with the same clock. The receivers can be operated separately, on adjacent frequency segments, or phase-locked together on the same frequency with different antennas. It offers 900 KHz bandwidth per channel.

The new AFEDRI LAN-IQ model is a stand-alone SDR that provides a built in touch screen interface and optional rotary tuning knobs. It maintains the USB and Ethernet interfaces that are compatible with the original SDR-Net.

The SDR-Net is simple to set up for ehternet network operation. The network mode allows it to be more easily used with a variety of computers, operating systems, and SDR software packages than does the USB mode. For review purposes, I was using SDR-Radio, version 1.5, build 1058. It recognizes the AFEDRI SDR-Net as a RFSpace NetSDR or SDR-IP. The image below shows some short wave broadcast monitoring in Sync-AM mode. SDR-Radio does support the RigCAT protocol, so it can be controlled from digital decoder software like fldigi.

Direct sampling SDRs give up approximately 6 dB of dynamic range per bit reduction in ADC resolution. So theoretically, this radio has 24 dB less dynamic range than the QS1R, or 12 dB less than the SDR-IQ. But the AFEDRI is 1/4 the cost of a $1K QS1R and 1/2 the cost of a $500 SDR-IQ. While I can tell the difference between it and the QS1R, the AFEDRI SDR-Net is as sensitive and selective as my Ten-Tec RX-320s and sounds as good or better than them and many other more expensive modern and boatanchor receivers.

The AFEDRI SDR-Net ($249 USD) and newer dual channel AFE822x SDR- ($359 USD) are well worth the price. (prices as of September 2020) . AFEDRI also has a newer "all in one" SDR with display/controls, the LAN-IQ SDR, for $339 - $364 depending on tuning knob options (none, mechanical, optical).