rpitx, we can transmit SSB using a single GPIO port from the Raspberry Pi. This of course uses square waves so creates a lot of harmonics.
If I were to use a couple of daisy-chained 70 cm bandpass filters on the GPIO output, would there be any harm in using this output for ham radio?
My aim would be to either connect it up to a PA, or to an upconvertor to go to 2.4 GHz for Es'hail-2 usage.
I understand that it wouldn't be the "cleanest" signal, but would be be legal and usable?