Change BS

I changed the BS 5% with another of 15 %. I tried to calculated the V/W of the PDs:

12599 is around 50
12595 is around 6

Now it is ok...more o less.

The power is 0.190 mW for both PDs. With this power the Voltage of 12599 is around 8 V. I noticed that with power more than around 600 mW the voltage of 12595 (pre-amp frascati) go to oscillation; i prefer apply a low power.

12599: out loop
12595: in loop

(I report only the out loop an the maximum value for G after that the signal go to oscillation)







12595: out loop
12599: in loop

12595: in loop



12599: in loop

I think a scheme is necessary: the situation is becoming too much confused. What beam splitter are we using, where are the PDs?

You are right.

BS 15 % ULO.

The PDs are in usual place...i am doing the outline.