SMD TGSL sensitivity problem

[ifrenide]

Hello everyone, I completed an SMD TGSL , but unfortunately I couldn't set the sensitivity to the point where it can chatters , GB and Disc works just fine , but the sensitivity is poor , I tried many ics instead of lm308, like OP07 , op37 genuine from analog devices , snd dual N channel jfet BFQ16 , but the sensitivity still not chattering,
can you give me some advices please.
thank you

[Artyom]

Hello everyone, I completed an SMD TGSL , but unfortunately I couldn't set the sensitivity to the point where it can chatters , GB and Disc works just fine , but the sensitivity is poor , I tried many ics instead of lm308, like OP07 , op37 genuine from analog devices , snd dual N channel jfet BFQ16 , but the sensitivity still not chattering,
can you give me some advices please.
thank you

Hello. To get started: 1. attach the circuit you used to assemble, 2. describe the coil data, turns, wire diameters, coil diameter, 3. what is the voltage swing on the transmitter coil, 4. what detection distance did you get and for what object?

[ifrenide]

I'm using a coil which is working just fine for another regular tgsl, all voltages , including tx ac signal is correct, I want to know what makes the tgsl chatters , what are the components that I have to play with other than the lm393 sens block ?

[Carl-NC]

Do you have an oscope? If so, measure signals in the TGSL-SMD and compare with signals in the TGSL. Most likely there is a wrong value R or C somewhere.

[ifrenide]

Hello Mr carl, yeah I do have a scope , I checked all values are correct, my mind now go everywhere in the pcb , audio block , band pass filters , anyway it is a good idea to check it with a working one which I will do , but the values I'm sure all of them are correct ones, the sens block doesn't offer a chettering threshold, I don't know why