Setting up a bank of WSPR skimmers
A couple of months ago I bought a KiwiSDR + BBG and, among other tests, tried running multiple instances of its WSPR extension. I was struck by the fact that its sensitivity appeared significantly better across the MF/HF bands compared to a Red Pitaya SDR122.88-16 with sdr_transceiver_wspr software that I’d been using as a WSPR skimmer for the previous three years. With the KiwiSDR and Red Pitaya sharing the same broadband vertical antenna through a high-quality skimmer, spots from the KiwiSDR showed SNR typically nearly 10 dB stronger.
After buying a second KiwiSDR + BBG, I’ve been experimenting with using them together as WSPR skimmers covering eight bands. For now I’ve tried using a Windows 10 PC with Firefox browser and eight pages open covering the receivers on the two KiwiSDR’s. This worked well, except that it caused the power supply I was using for the KiwiSDR's to run really hot (a replacement is due shortly).
If I stick with using the two KiwiSDR’s for WSPR skimming, I’m wondering about some questions:
1) I’d like to go with a lighter-weight device to run the web client, instead of the Win 10 box. One option would be a Raspberry Pi 3B+ or 4B with Raspbian. Do one of these seem like it would be up to running the eight web browser instances? I assume that waterfall displays should be disabled to keep down the processing burden on both the KiwiSDR’s and the R Pi.
2) Is there any other way to do the WSPR instances besides use of a running web client as noted above? In case of a power loss, it would be great if all the pieces could auto-boot and restart skimming. Is this possible, or would I always be looking at manual config for each band after the components are restarted?
3) I was thinking about mounting the two KiwiSDR’s together in a shared metal case, with a quiet fan sized to cool both of them. Apart from thermal considerations, are there any reasons (RF issues?) to avoid that?
4) Are there any reasons to enable GPS if the KiwiSDR's are devoted only to WSPR? Or do they default to getting sufficient clock accuracy through, say, internet ntp?
Thanks for any possible thoughts.
Comments
Wsprdaemon to the rescue. Or at least WSPR autorun to eliminate the browser connections.
Could someone else answer this in detail please? I'm fighting way too many fires right now. And there's a cyclone inbound..
No need for browsers.... see:
and yes, you'll still want GPS
wsprdaemon is the way to go, designed for exactly this and more.
Two in a case should not be a problem, I ran two in a metal 3.5" hard drive enclosure for ages.
I'm not saying try a hard drive enclosure as it is tight (height mainly) but two Kiwi in a case is fine and I had a single 60mm fan just ticking over to move air, to be honest with a really close metal case with decent vents the fan wasn't needed in UK-range temperatures.
I have 4 running with BBAI. 2 of the 4 run 13 ch each of wspr on 2 different antennas. I cool all 4 with one high qulaity AC power fan
Thanks!
Is there a KiwiSDR-specific tutorial on setting up wsprdaemon?
The wsprdaemon folks have a page with help and a forum: http://wsprdaemon.org/index.html
The Kiwi admin page, extensions tab, WSPR section, lets you setup some or all of your Kiwi's channels to "autorun" the WSPR extension on a particular band (or even band hopping) without a browser connection. On the admin status tab you can see them connected, looking like normal user connections, and also displaying spot decode counts which is useful.
But If you can deal with setting up wsprdaemon on a separate computer (an RPi 4 is fine) then it is superior, by a long margin, to the Kiwi WSPR extension (which is really just a toy and the first-developed extension as a demonstration of the concept).
Yes. Go to wsprdaemon.org and look it over. A greenfield tutorial is at https://github.com/rrobinett/wsprdaemon
and in general the problem of getting the most performance from a KiwiSDR is discussed at length, in its various aspects at
While much of the interest is slightly parallel to yours, WSPR rather than CW skimming, the goals are very similar and you should find a lot worth considering there.
Thanks, think I gleaned enough to try setting up wsprdaemon. Will give it a go as soon as I can put my hands on the microHDMI adapter for my RPi 4 (funny how there always seems to be one show-stopper bit/bob).
you can run the Rpi headless and not need hdmi
Good tip there on enabling ssh without the use of a local console. I didn't realize I could ssh to a new OS that had just been installed from .iso file, but using the trick of placing a file called "ssh" on the SD card got it to work.
The wsprdaemon install completed without issues, and after configuring the KiwiSDR for eight receivers, WSPR spots are now rolling in. When a new power supply arrives tomorrow, I'll try adding the second KiwiSDR.
Thanks to all of the above posters for the help/suggestions.
next you need to swap your BBG to BBAI and run more RX on a single kiwi! :-)
BBAI sounds worthwhile. Is that just a straight swap, or is there more config involved? If the latter, anything good to read on that?