Thanks to the work (hardware&software) of various OM (SV1AFN, NT7S etc...) I would like to share this code for Arduino IDE and NodeMCU board to build a small beacon for up to three band with simultaneus tx on three frequency.
https://github.com/iw5ejm/multibandWSPR_nodeMCU
It works with a si5351a synthesizer and a nodeMCU (or clone esp826* board like wemos d1 lite mini) which, connected to your home wifi, retrive correct time for correct timed wspr transmissions via NTP server. No gps required.
It's nothing of original or new, only an assembly of blocks but it could be usefull because ready to use!
73's de Marco IW5EJM