Hi. These tutorials are really helpful. Better explained than most of the books. Although I have a doubt. At 10:30 you said Vo = V1' - V2'. At 11:21 you said Vo = |V1'| - |V2'| . Since both V1' & V2' are having different phases, the above two statements become contradictory. Kindly explain.
Howdy again. I did some experimenting. With values of the coupling capacitor and the choke tuning to series resonence I observed a 90 degrees phase shift over the choke. So I believe the term RF choke is misleading. I would call it an inductor. I used 47 pF and 3,9 uH in series. I fed the circuit 10,7 MHz with my signal generator. I observed phase shifting increase and decrease when changing the frequency. Regards again.
Howdy. Otherwise good. I don't understand the phase shifting though. Assuming zero deviation. What brings about the +-90 degrees shift ? The coupling capacitor perhaps ? I would say the capacitor must be heavily loaded. Then the current is -90 degrees, yes. Regards.
I think you are in error at the end .. you HAVE TO use a limiter on a FS discriminator because it is sensitive to amplitude and phase.. so you want to take the amplitude portion out.
After watching her next video (58), I think what she meant to say was that there isn't a built in limiter in the foster seeley circuit so the disadvantage is that you would have to put a limiter upstream, whereas in the ratio detector in the next video, it has one built in so its advantage is that it doesn't need a limiter.
