RX888 | The SWLing Post

Jinze (Justin) Peng, developer of the high performing, high value RX-888 SDR, has just announced an improved “MK II” version.

I’ve been very pleased with my original RX-888 in all performance aspects, and it’s wideband demodulation and IQ WAV recording have opened up new DXing possibilities (small capacity hard drives need not apply :^)

The new receiver is now appearing on eBay and AliExpress.

Details:

We are pleased to announce the second-gen of RX888. RX888 mkII is the new generation of RX888 with the following improvements and enhancements:

1. Add a tunable (variable) attenuator in the HF path, which can tune from 0 to -31.5dB.

2. Change the fixed LNA of RX888 to a VGA, which gives the -10dB to +33dB range. VGA applies to both HF and VHF.

3. Use the newer generation of tuner chip R828D instead of R820T2.

4. Use an enhanced version of 64M LPF to improve image rejection further.

5. A jumper can select the internal reference clock or an external 27Mhz reference clock.

The primary motivation is giving users smaller granularity control on the RF front-end and a big dynamic range to fit the demands of both strong and weak signals receiving. The tunable range is -41.5dB to +33dB for HF and 0db to 55dB for VHF, which covers most use cases.

During the mkII development, we are working very closely with the original author of BBRF103, IK1XPV, on his new universal driver. The new driver supports RX888 and RX888 mkII now. The new driver can download here: https://github.com/ik1xpv/ExtIO_sddc. And we expect the power of open source will significantly improve the software support and the lifetime of RX888.

Guy Atkins is a Sr. Graphic Designer for T-Mobile and lives near Seattle, Washington. He’s a regular contributor to the SWLing Post.

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I received my new RX888 SDR receiver today, via DHL shipping in only seven days from ordering on Ebay from seller “shenglongsi”. I’ve noticed that some Chinese Ebay sellers use a placeholder shipping number when choosing the DHL carrier, and then some days later they forward the actual shipping number when the product is out the door. That was the case with the RX888– four days in limbo, and then BINGO!–a real tracking number was sent and the package arrived three days later.

It should be noted right up front, as others have pointed out, the RX666 and RX888 SDRs are commercial implementations of the excellent, open source BBRF103 receiver. The BBRF103 is the creation of talented Italian designer Oscar Steila IK1XPV.

Hopefully tonight I’ll be sorting out files to get the radio operating, and if there are hiccups along the way I have help from some other early adopters around the globe.

The radio arrived with zero documentation or links to support files, but I already have files known to work with the RX666. The receiver should work with HDSDR after the correct additional files are added to the HDSDR folder, as does the similar RX666 model. Cypress USB drivers also need installation on the host computer. One concern is operating the LNA (low noise amplifier) on the RX888, which the RX666 lacks. This may take a different EXTIO .dll file than the one intended for the earlier RX666.

I’m aware of the developer of another popular SDR program who will almost certainly add support for the RX888/RX666 to his software.

I’ve read that the powerful ADC chip inside these two models is a USD ~$60-70 component (or from the same chip series) which is also found in a few commercial grade SDRs plus the newer WinRadio G33DDC & G35DDCi models. Translation? The RX666 & RX888 could turn out to be amazing performers for the price.

Below are up-close pictures of the receiver’s printed circuit board. Construction and soldering look quite good considering the USD $188 price. In my opinion the build quality appears to somewhat exceed that of the RX666, which was the first of these two units on the market.

Note that in the last photo the whitish square on the bottom of the PCB is a thick foam pad, perhaps some thermal transfer material. It is sticky-backed and placed so that it’s wedged between the bottom of the chip (ADC?) with the blue heat sink and the bottom of the case.

In the below photo, note the small LEDs with indications “PWR”, “MODE”, “OVLF”, and “MODE” (again). At the upper-right corner are two pads marked “RST” (reset?).