The Ultimate3 QRSS/WSPR Transmitter Kit is the third version in the "Ultimate" QRSS/WSPR kit trilogy. It can produce QRSS, Hell, WSPR, Opera and PI4 slow-signal modes anywhere from audio to 10m and above. Plug-in LPF filters are available for all 12 HF/MF/LF bands.
The price is USD $29.00. To order please visit QRP Labs.The Ultimate 3 is probably the lowest cost beacon available. I still have my unbuilt kit awaiting better health to build, although several kind folk have offered to build mine for me. Jay W5OLF kindly supplied me a 10m 500mW, single PCB, WSPR beacon (WSPR-AXE-CW) ready assembled and that has blown me away: it has been copied in every continent on 10m. The Ultimate 3 is the more flexible design but the WSPR-AXE-CW is an ideal tiny WSPR only beacon.
My Ultimate 3 kit was ordered with GPS, but it was supplied without this, but with an extra PCB - I think I got the wrong order. I really should write to Hans Summers, but I have been too unwell. For now, the kit remains unbuilt. I intend to build it when I am fitter and less clumsy, hopefully in 2015.