Vijit Dubey
Member
I understand but this looks good enough.For giggles and kicks I tried to make the tank circuit with an oscillator with <10mΩ source impedance but not consume much power driving the series tank circuit.
It was a bit problematic but it oscillated at resonant frequency. The challenge was to get Barkausen criteria with positive feedback and minimal DC offset into a 50mΩ current shunt with negative feedback for DC operating point and not suck much current. I used +/- 3.7V to DC couple and prevent DC current thru the inductor.
But in the time I spent on it, it wasn't good enough to be reliable for a wide range of LC values.
View attachment 94455
To make a good sample and hold , you can use CMOS analog switches but low bias FET input OP Amps and low leakage caps ( Plastic film)
I have a question. Let's say I have a system which sweeping so fast that it is going through the resonant frequency. If I want to make it more sluggish or let us say I want it to lock some KHz above the resonant frequency (so that it is more practical), how would I go about it?