After a lot of testing with my various radios (analog and SDR), I was amazed just how well the Airspy HF+ Discovery receiver did against my IC-7300 when I setup a dedicated QRSS 22 m monitor and web page. Only it and the IC-7300 could hear the QRSS 5mW WSPR and FSK CW and CW signals and only the IC-7300 had a slightly better minimum discernable signal (MDS) but at 10x the price!Radios also compared where the RX-888 Mk II, RSPduo, FLEX-1500, KiwiSDR, RTL-SDR. I was able to use Simon Brown's awesome SDR Console to drive the Airspy, RX-888, RSPduo and RTL-SDR and create multiple (three) virtual receivers using VAC to feed various DSP decoding software. Any receiver, even an SA612 DCR will do a decent job with strong signals, but once you get down below into the noise then receiver MDS comes into play along with receiver dynamic range and real analog band specific filters. Specs are one thing but seeing the difference in the waterfall in another.
I also have the PTRX-7300 panapter board that I installed using the full HF bandwidth modification so it can share the same receiving antenna with the IC-7300 but bypasses the IC-7300's RF filters so you use the ones (analog or software) that come with the other connected receiver (makes A/B comparisions easier with the IC-7300 as the control). So I have the Airspy connected to the PTRX-7300 and it and IC-7300 share the same antenna system in receive mode. Albeit I'm only using one vertical antenna for receiving from 40 to 10 m feeding multiple receivers using a 5-port active antenna multi-coupler.
The 912 kHz (maximum) bandwidth of the Airspy allows one to monitor the entire 22 m and 20 m bands using SDR Console in multiple modes, AGC and receiver IF settings, etc. I've attached a screen capture. Currently, I'm monitoring the 22 m "sweet spot" but can see a lot of signals farther up and for 20 m, I'm simultaneously receiving FT8 and JS8. The IC-7300 is receiving SSTV since it can dig out signals that are a tad weaker. My KiwiSDR is spotting WSPR signals from 22 m to 10 m to the WSPRnet. I use the RTL-SDR for decoding (using SDR# and the Calico CAT Kenwood emulator) and uploading NOAA APT weather satellite images (using WXtoImg) since it does as well on VHF as the Airspy.
I changed the palette used with the Spectrum Lab 22 m decoder to make it easier to spot the QRSS and WSPR signals with the eye. It also makes signal level comparisons easier when I flip through the saved images and can compare times when the signals fade in and then fade out each day due to diurnal effects and perhaps how space weather affects the band since it's similar enough to 20 m. A strong X-ray flare can really shake and rattle a QRSS waterfall.
If I had it to do all over again, I wouldn't have bought the RX-888 Mk II or RSPduo receivers but nothing ventured, nothing gained.
73,
Robert
www.va3rom.com
---------------------------------------------------------------
File Attachment 1: SDRConsole_x_Airspy.jpg