Lock-in amplifier on Red Pitaya? Why not!
Well seriously: the idea of its implementation on Red Pitaya seems great. All resources are there - including the reference generator. 60/10 MHz BW (125 Msps) seems more than sufficient, the complete pair is in place already (14bit DAC/ADC), PLL - can be realized in several ways and then the DSP part would have to be done.
Apparently the fact that it has not been implemented yet is just due to the fact that lock-in amps are not as frequently used as scopes, spectrum analyzers and similar, so first applications rather naturally had to cover that part.
In any case - the workload to complete the lock-in amplifier is not to be underestimated.
rokH