I worked around the PSL table today.
The Y+PSL output from the optical fiber module for FOL was fed to the input of the Thorlabs FPD310.
200uW of incident light on the RFPD gave an RF signal of -70dBm as measured on a spectrum analyzer.
I swapped the beam splitter along the PSL path so that the incident power on the RFPD is ~1.5mW (Maximum incident power that the PD can tolerate is ~2mW).
This RF signal generated was - 43dBm which is still small for the input to the frequency counter module.
I checked this with a function generator and found that the frequency counter requires around -25 to -30 dBm at the input.
I plan to use the Minicircuits ZFL-1000ln that is on the IOO rack but not being used (This was used for green beatnote amplification but is not required/used anymore) to amplify the RF signal to the frequency counter.
If anyone has any objections to using this amplifier for the frequency counter, let me know.