The POP22/110 RFPD has been replaced by PDA10CF. As a result the 22 and 110 MHz signals became detectable.
However the signal level maybe too low according to a quick look with an RF spectrum analyzer.
The level at 22 and 110 MHz were both approximately -70 dBm although these values were measured when the central part was freely swinging.
Perhaps we need to amplify the signals depending on the actual SNR.
Also I have updated the optical tables' wiki page :
I will replace it by PDA10CF, which is made from InGaAs and supposed to have 10 times bigger responsibility.